JP6950719B2 - Liquid lead-acid batteries, idling stop vehicles and micro-hybrid vehicles - Google Patents

Description

The present invention relates to a lead storage battery, an idling stop vehicle and a microhybrid vehicle.

In recent years, various fuel efficiency improvement measures have been studied for automobiles in order to prevent air pollution or global warming. Vehicles with measures to improve fuel efficiency include, for example, micro-hybrid vehicles such as idling stop system vehicles (hereinafter referred to as "ISS vehicles") that shorten the operating time of the engine and power generation control vehicles that reduce the power generation of the alternator by the power of the engine. Cars are being considered.

In the ISS vehicle, the number of times the engine is started increases, so that the large current discharge of the lead storage battery is repeated. Further, in the ISS vehicle and the micro-hybrid vehicle, the amount of power generated by the alternator is reduced, and the lead-acid battery is charged intermittently, resulting in insufficient charging. Therefore, the lead-acid battery used in the ISS vehicle and the micro-hybrid vehicle is used in a partially charged state called PSOC (Partial State Of Charge). When a lead-acid battery is used under PSOC, it has a shorter life than when it is used in a fully charged state.

In recent years, in Europe, the rechargeability of lead-acid batteries during the charge / discharge cycle in accordance with the control of micro-hybrid vehicles has been regarded as important, and DCA (Dynamic) is used as an evaluation standard for the charge performance of lead-acid batteries during the charge / discharge cycle. Charge Access) evaluation is being standardized. That is, in Europe, the DCA performance of lead-acid batteries used in a partially charged state called PSOC is regarded as important.

On the other hand, as a means for improving cycle life characteristics (hereinafter referred to as "cycle characteristics") and charging performance, the following Patent Document 1 describes carbon having a hollow shell structure, bisphenols and sulfites or amino acids. A technique relating to a lead-acid battery including a negative electrode active material containing a formaldehyde condensate of the above is disclosed.

Japanese Unexamined Patent Publication No. 2003-338285

By the way, in the ISS vehicle and the micro-hybrid vehicle, a large current charge of the lead storage battery is repeated by regenerative charging or the like for a short time. It is known that when high current charging is repeated, electrolysis of water in the electrolytic solution occurs. When electrolysis occurs, oxygen gas and hydrogen gas generated by the decomposition of water are discharged to the outside of the battery, so that the amount of water in the electrolytic solution is reduced. Further, when water in the electrolytic solution volatilizes due to an increase in the temperature inside the battery and mist of the electrolytic solution is generated, the mist of the electrolytic solution is discharged through an exhaust plug for discharging the gas, thereby further electrolyzing. The amount of water in the liquid decreases. As a result, the concentration of sulfuric acid in the electrolytic solution increases, and the capacity decreases due to corrosion deterioration of the positive electrode and the like. In addition, when the liquid level of the electrolytic solution drops and the electrode (negative electrode, etc.) is exposed from the electrolytic solution, the discharge capacity drops sharply, the connection between the electrode (negative electrode, etc.) and the strap, or the strap itself corrodes. There is a problem. For this reason, when the amount of water in the electrolyte of the lead-acid battery decreases, it is necessary to replenish the reduced amount of water for maintenance. Therefore, lead-acid batteries are required to suppress the decrease in water in the electrolytic solution from the viewpoint of maintenance-free operation. Especially in Europe, since maintenance is not performed as a standard, suppressing the decrease in the electrolytic solution is an important issue along with the improvement of DCA performance.

On the other hand, in the method of Patent Document 1, the suppression of the reduction of the electrolytic solution is not sufficient, and it is difficult to achieve both the suppression of the reduction and the DCA performance.

Therefore, an object of the present invention is to provide a lead-acid battery capable of achieving both liquid reduction suppression performance and DCA performance, and an idling stop vehicle and a micro-hybrid vehicle equipped with the lead-acid battery.

As a result of diligent studies, the present inventors have been able to achieve both suppression of liquid reduction and DCA performance by incorporating a carbon material having a specific specific surface area and a specific additive into the negative electrode active material. We found what we could do and came to complete the present invention.

One aspect of the present invention includes a battery case having a cell chamber and an open upper surface, an electrode group and an electrolytic solution housed in the cell chamber, and a lid for closing the opening. A lead-acid battery having a negative electrode and a positive electrode, the negative electrode having a negative electrode active material containing a Pb component, lignin sulfonic acid and / or a salt thereof, and ^{a carbon material having a specific surface area of 10.0 m 2 / g or less.} Regarding.

According to this lead-acid battery, it is possible to achieve both suppression of liquid reduction and DCA performance. Further, according to this lead-acid battery, the cycle characteristics (DOD 17.5% life performance) evaluated according to the EN standard (European unified standard) can be sufficient. That is, according to one aspect of the present invention, it is possible to provide a lead-acid battery that can satisfy the performance required in Europe as the performance of the lead-acid battery used in a micro-hybrid vehicle.

In one embodiment, the content of lignin sulfonic acid and a salt thereof is 0.05 to 0.5% by mass based on the total mass of the negative electrode active material.

In one embodiment, the content of the carbon material is 0.2 to 3.5% by mass based on the total mass of the negative electrode active material.

In one aspect, the lid is an exhaust formed between a first lid portion, a second lid portion provided on the first lid portion, and a first lid portion and a second lid portion. The bottom wall of the first lid portion having a chamber and separating the exhaust chamber and the cell chamber is provided with a reflux hole for refluxing the electrolytic solution into the cell chamber.

In one aspect, assuming that the width of the cell chamber is X mm and the thickness of the electrode group is Y mm, X and Y satisfy the following conditional equations.
-1.1 ≤ XY ≤ 1.2

In one embodiment, the distance between the adjacent negative electrode and the positive electrode is 0.4 to 0.8 mm.

In one embodiment, the specific surface area of the carbon material is 7.0 m ² / g or less or 1.0 m ² / g or less.

Another aspect of the present invention relates to an idling stop system vehicle including the lead-acid battery.

Another aspect of the present invention relates to a micro-hybrid vehicle including the lead-acid battery.

According to the lead-acid battery of the present invention, both the liquid reduction suppressing performance and the DCA performance can be achieved at the same time. Further, according to the present invention, it is possible to provide an application of a lead storage battery to a micro-hybrid vehicle. Further, according to the present invention, it is possible to provide an application of a lead storage battery to an idling stop vehicle. That is, according to the present invention, it is possible to provide an idling stop vehicle and a micro-hybrid vehicle provided with the lead storage battery capable of achieving both the liquid reduction suppressing performance and the DCA performance.

FIG. 1 is a perspective view showing the overall configuration and internal structure of the lead storage battery according to the embodiment. FIG. 2 is a perspective view showing an electric tank used for the lead storage battery of FIG. FIG. 3 is a cross-sectional view taken along the line III-III of FIG. FIG. 4 is a plan view of the first lid portion used in the lead storage battery of FIG. FIG. 5 is a bottom view of the second lid portion used for the lead storage battery of FIG. FIG. 6 is a cross-sectional view of the lid along the VI-VI line of FIG. FIG. 7 is a perspective view of a group of plates used in the lead-acid battery of FIG. FIG. 8 is a side view of the electrode plate group of FIG. 7 as viewed from the stacking direction of the electrode plates.

Hereinafter, embodiments of the present invention will be described in detail.

<Lead-acid battery>
FIG. 1 is a perspective view showing the overall configuration of the lead storage battery of one embodiment. The lead-acid battery 1 shown in FIG. 1 is a liquid lead-acid battery. As shown in FIG. 1, the lead-acid battery 1 according to the present embodiment includes an electric tank 2 having an open upper surface, a lid 3 for closing the opening of the electric tank 2, and a group of electrode plates housed in the electric tank 2. It includes an electrode group) and an electrolytic solution (not shown).

(Electric tank)
FIG. 2 is a perspective view showing an electric tank used for the lead storage battery of FIG. 1, and FIG. 3 is a cross-sectional view taken along the line III-III of FIG. As shown in FIGS. 2 and 3, the electric tank 2 has a rectangular parallelepiped shape, and has a rectangular bottom surface portion, a pair of longitudinal side surface portions adjacent to the long side portion of the bottom surface portion, and a short side portion of the bottom surface portion. It consists of a pair of short side surfaces adjacent to. In the following, the direction along the long side portion of the bottom surface portion and the direction along the short side portion of the bottom surface portion are defined as the longitudinal direction and the lateral direction of the battery case 2, respectively. The battery case 2 is made of polypropylene, for example.

The inside of the electric tank 2 is divided into 6 sections by five partition walls 21, and the first to sixth cell chambers 22a to 22f (hereinafter, in some cases, depending on the case) are arranged along the longitudinal direction of the electric tank 2. A "cell chamber 22") is formed. The cell chamber 22 is a space in which a group of plates is inserted. The electrode plate group is housed in each cell chamber 22 of the electric tank 2 so that the stacking direction of the electrode plates is the longitudinal direction of the electric tank 2. The electrode plate group is also called a cell, and has an electromotive force of 2V. In order to drive an electric component for an automobile by stepping up or lowering a DC voltage of 12V, six electrode plates are connected in series to make 2V × 6 = 12V. Therefore, when the lead-acid battery 1 is used as an electrical component for an automobile, six cell chambers are required. When the lead-acid battery 1 is used for other purposes, the number of cell chambers is not limited to six.

As shown in FIGS. 2 and 3, both side surfaces of the partition wall 21 and the pair of inner wall surfaces 23 facing the partition wall 21 of the battery battery 2 are in the height direction of the battery battery 2 (direction perpendicular to the opening surface). A plurality of ribs (rib portions) 24 extending to the surface may be provided. That is, the partition wall 21 may have a flat portion 25 and a plurality of ribs 24 extending in the height direction of the electric tank 2 raised from the flat portion 25. The rib 24 has a function of appropriately pressurizing (compressing) the electrode plate group inserted into the cell chamber 22 in the stacking direction of the electrode plates.

The width X of each cell chamber 22 can be adjusted by adjusting the height of the rib 24 and the like. The widths of the plurality of cell chambers 22 may be the same or different. In the present specification, when the partition wall 21 does not have the rib 24, the width X of the cell chamber is the shortest distance between the partition walls 21 facing each other, or the inner wall surface of the partition wall 21 and the electric tank 2 facing the partition wall 21. It is defined as the shortest distance to and from 23 (hereinafter referred to as "wall-to-wall distance Xa"). When the partition wall 21 and / or the inner wall surface 23 of the electric tank 2 has ribs, the width X of the cell chamber is defined as the value obtained by subtracting the height Ha of the highest rib from the distance Xa between the walls (see FIG. 3). .). For example, when the height Ha of the ribs of the two facing partition walls 21 is the same, the width X of the cell chamber is [distance between walls Xa] − (2 × [height Ha of ribs]).

(lid)
As shown in FIG. 1, the lid 3 has a double lid structure composed of a first lid portion 4 and a second lid portion 5, and the first lid portion 4 and the second lid portion 5 and the lid 3 have a double lid structure. A plurality of exhaust chambers D1 to D6 are formed between them. That is, the lid 3 has a first lid portion 4, a second lid portion 5, and an exhaust chamber formed between the first lid portion 4 and the second lid portion 5. The lid 3 has a substantially rectangular shape in a plan view, and one end and the other end in the longitudinal direction of the lid 3 are attached to one end and the other end in the longitudinal direction of the battery case 2 in each direction along the four sides of the rectangle. The lid 3 is provided on the electric tank 2 in a state in which one end and the other end in the lateral direction of the lid 3 are aligned with each other and the one end and the other end in the lateral direction of the electric tank 2 are aligned with each other. The lid 3 (first lid portion 4 and second lid portion 5) is made of, for example, polypropylene.

The lid 3 is formed with a hollow protruding portion 6 projecting upward from the upper surface of the first lid portion 4 in a region of the upper surface of the first lid portion 4 where the second lid portion 5 is not provided. ing. An indicator mounting hole 7 is formed in a part of the protruding portion 6. The indicator mounting hole 7 is used for mounting an indicator (not shown) that displays the liquid level of the electrolytic solution in the battery case. In the present embodiment, an indicator mounting hole 7 is provided above the cell chamber of one of the cell chambers provided in the battery case 2, and an indicator indicating the liquid level of the electrolytic solution in the cell chamber is provided. It can be mounted in the indicator mounting hole 7. In the present embodiment, the liquid level of the electrolytic solution in another cell chamber is estimated by displaying the liquid level of the electrolytic solution in one cell chamber on the indicator.

The lid 3 is formed with a negative electrode terminal 8 and a positive electrode terminal 9 in a region of the upper surface of the first lid portion 4 where the second lid portion 5 is not provided. The negative electrode terminal 8 and the positive electrode terminal 9 are connected to a group of electrode plates housed in the battery case 2 via a negative electrode column and a positive electrode column.

Hereinafter, the details of the lid 3 will be described with reference to FIGS. 4 to 6. FIG. 4 is a plan view of the first lid portion, and FIG. 5 is a bottom view of the second lid portion. FIG. 6 is a cross-sectional view taken along the line VI-VI of FIG. 4, and is a cross-sectional view of the lid 3 in a state where the first lid portion 4 and the second lid portion 5 are welded together.

As shown in FIG. 4, the first lid portion 4 has a substantially rectangular shape in a plan view, and a second lid portion 5 is arranged on a part of the first lid portion 4. The exhaust chamber component 400 is formed. The exhaust chamber component 400 has one end 400a and the other end 400b in the longitudinal direction positioned closer to one end 4a and the other end 4b in the longitudinal direction of the first lid 4, respectively, and one end 400c in the lateral direction is the first. The lid 4 is located near the center of the lid 4 in the lateral direction, and the other end 400d in the lateral direction is located near the other end 4d of the first lid 4 in the lateral direction (the lateral direction of the battery case). It is formed in the state of being made to. A peripheral wall portion 40 extending along the outer peripheral edge thereof is formed on the upper surface of the exhaust chamber constituent portion 400, and a first lid-side recess is formed inside the peripheral wall portion 40. In the example shown in FIG. 4, in order to increase the width dimension (length in the lateral direction) of the portion closer to one end 4a and the other end 4b in the longitudinal direction of the exhaust chamber component 400, the exhaust chamber component 400 Projecting portions 401 and 402 are formed so as to project to one end side in the lateral direction with respect to the portion closer to the center in the longitudinal direction of the above.

As shown in FIG. 5, the second lid portion 5 has the same contour shape as the exhaust chamber component portion 400, and the exhaust chamber configuration is formed on one end 5a side and the other end 5b side in the longitudinal direction, respectively. Similar to the protrusions 401 and 402 at both ends of the portion 400, the protrusions 501 and 502 protruding in the lateral direction are formed. Further, as shown in FIG. 5, a peripheral wall portion 50 extending along the outer peripheral edge thereof is also formed on the lower surface of the second lid portion 5, and a second lid portion side recess is formed inside the peripheral wall portion 50. ing. In the example shown in FIG. 5, an outer wall portion 51 that surrounds the outside of the peripheral wall portion 50 is formed on the lower surface of the second lid portion 5.

The second lid portion 5 is provided on the exhaust chamber constituent portion 400, and the first lid portion 4 and the second lid portion 5 are joined by heat welding. Specifically, in the second lid portion 5, the one end 5a and the other end 5b of the second lid portion 5 in the longitudinal direction are made to coincide with the one end 4a and the other end 4b of the first lid portion 4 in the longitudinal direction, respectively. , One end 5c and the other end 5d in the lateral direction of the second lid portion 5 are aligned with the lateral end 400c and the other end 400d of the exhaust chamber constituent portion of the first lid portion 4, respectively. It is arranged on the component 400. Further, the exhaust chamber constituent portion 400 and the second lid portion 5 are joined in a state where the peripheral wall portion 40 and the peripheral wall portion 50 are combined, and the first lid portion side recess and the second lid portion side are joined. A space for forming an exhaust chamber is formed between the exhaust chamber constituent portion 400 of the first lid portion 4 and the second lid portion 5 by the recess.

In the space between the exhaust chamber constituent portion 400 of the first lid portion 4 and the second lid portion 5, the first to sixth cell chambers 22a to 22f are respectively located on the first to sixth cell chambers 22a to 22f. Exhaust chambers D1 to D6 of No. 6 are formed (see FIGS. 4 and 5). These exhaust chambers are first partition wall portions having a predetermined pattern formed inside the exhaust chamber constituent portion 400 of the first lid portion 4 and the peripheral wall portion 50 of the second lid portion 5 with a predetermined plate thickness. It is formed by joining 42 and 52 to each other. The exhaust chambers D1 to D6 have a function of retaining the mist of the electrolytic solution generated from each cell chamber 22 in the electric tank 2 inside and refluxing the electrolytic solution liquefied in the exhaust chamber into each cell chamber 22. ..

In the present embodiment, a part of the first exhaust chamber D1 and the sixth exhaust chamber D6 arranged at both ends is provided with a first partition portion provided on the first lid portion 4 and the second lid portion 5. By partitioning by the second partition walls 42a and 52a formed in a part of 42 and 52, one end 400a side and the other end 400b side of the exhaust chamber component 400 of the first lid 4 in the longitudinal direction, and the other end 400b side, and Centralized exhaust chambers E1 and E2 are formed on one end 5a side and the other end 5b side of the second lid portion 5 in the longitudinal direction, respectively.

Each exhaust chamber is a pair of inner side surfaces Sa and Sb in the longitudinal direction facing each other in a state facing the longitudinal direction of the first lid portion 4, and a pair facing each other in a state facing the lateral side of the first lid portion 4. It has inner side surfaces Sc and Sd in the lateral direction, and four corner portions C1 to C4 are formed in each exhaust chamber. In the present specification, for convenience of explanation, among the four inner side surfaces Sa to Sd of each exhaust chamber, the inner side surfaces Sa and Sb facing the longitudinal direction of the first lid portion 4 are referred to as longitudinal inner surfaces, and the first The inner side surfaces Sc and Sd of the lid portion 4 of 1 facing the lateral side are referred to as the lateral side surfaces in the lateral direction.

In the three exhaust chambers D1 to D3 arranged closer to one end 4a in the longitudinal direction of the first lid portion 4, the first lid portion 4 of the pair of inner side surfaces in the longitudinal direction of the first lid portion 4 The inner side surface in the longitudinal direction located on the one end 4a side in the longitudinal direction is one longitudinal inner surface Sa, and the inner side surface in the longitudinal direction located on the other end 4b side in the longitudinal direction of the first lid 4 is the other longitudinal direction. The inner surface is Sb. Further, in the other three exhaust chambers D4 to D6 arranged near the other end 4b in the longitudinal direction of the first lid portion 4, among the pair of inner surfaces in the longitudinal direction, the longitudinal length of the first lid portion 4 The longitudinal inner surface located on the other end 4b side of the direction is defined as one longitudinal inner surface Sa, and the longitudinal inner surface located on the longitudinal end 4a side of the first lid 4 is the other longitudinal inner surface. It is Sb.

The exhaust chambers D1 to D6 are formed in a substantially square shape in a plan view, but the first exhaust chambers D1 and the sixth exhaust chambers D6 arranged at both ends in the longitudinal direction of the first lid portion 4 are respectively. Since the centralized exhaust chambers E1 and E2 are formed in a part of the above, one of the inner side surfaces Sa in the longitudinal direction has a deformed shape.

As described above, the exhaust chambers D1 to D6 and the centralized exhaust chambers E1 and E2 are formed between the exhaust chamber constituent portion 400 of the first lid portion 4 and the second lid portion 5, and further. As will be described later, various fluid passages for connecting the exhaust chambers D1 to D6 to the centralized exhaust chambers E1 and E2 are formed. These fluid passages are composed of first partition wall portions 42 and 52 provided on the first lid portion 4 and the second lid portion 5 and joined to each other, respectively. The configuration of the fluid passage provided between the first lid portion 4 and the second lid portion 5 will be described with reference to FIG. 4 showing the lid portion 4. The patterns of the wall portions provided on the first lid portion and the second lid portion to form the exhaust chamber, the fluid passage, and the like are in a mirror image relationship with each other.

As shown in FIG. 4, between the exhaust chamber component 400 of the first lid 4 and the second lid 5, a first longitudinal fluid passage L1 and a second longitudinal fluid passage L2 , The first fluid passage W1a in the lateral direction and the second fluid passage W1b in the lateral direction are formed.

The first longitudinal fluid passage L1 is on the other end 400d side of the exhaust chamber component 400 in the lateral direction, and the outside of the exhaust chambers D1 to D6 (between the exhaust chambers D1 to D6 and the peripheral wall portion 40) is the exhaust chamber. It is provided so as to extend linearly along the longitudinal direction of the component 400. On one end side and the other end side of the first longitudinal fluid passage L1 in the longitudinal direction, width dimensions (length in the lateral direction) are provided at positions corresponding to the protrusions 401 and 402 of the exhaust chamber component 400, respectively. The enlarged enlarged portions L11 and L12 are formed. The end portions of the enlarged portions L11 and L12 of the first longitudinal fluid passage L1 are formed between the first exhaust chamber D1 and the sixth exhaust chamber D6 and the peripheral wall portion 40, respectively. Through 44, it is connected to the centralized exhaust chambers E1 and E2.

The second longitudinal fluid passage L2 is linear at one end 400c side of the exhaust chamber component 400 in the lateral direction and outside the exhaust chambers D1 to D6 (between the exhaust chambers D1 to D6 and the peripheral wall portion 40). It is provided so as to extend. The first lateral fluid passage W1a and the second lateral fluid passage W1b are adjacent to each other between the second and third exhaust chambers D2 and D3 and the fourth and fifth exhaust chambers D4 and D5, respectively. The space is provided so as to extend in the lateral direction of the exhaust chamber component 400, and connects between the first longitudinal fluid passage L1 and the second longitudinal fluid passage L2.

The second longitudinal fluid passage L2 is divided into a first portion L2a and a second portion L2b by a partition wall portion 45 provided at the central portion in the longitudinal direction of the exhaust chamber constituent portion 400. The first longitudinal fluid passage L1 passes through the first lateral fluid passage W1a and the second lateral fluid passage W1b, and the first portion L2a and the second portion of the second longitudinal fluid passage L2. They are connected to L2b respectively.

As shown in FIG. 4, the exhaust chambers D1 to D6 are injected with an electrolytic solution that penetrates the bottom wall of each exhaust chamber that partitions between each exhaust chamber and the corresponding cell chambers 22a to 22f. A reflux hole h having a size that also serves as a hole is provided. The return hole h is formed between one longitudinal inner surface Sa of each exhaust chamber and one lateral inner surface Sc of each exhaust chamber located on the second longitudinal fluid passage L2 side. It is located near the corner portion C1 of No. 1, and only one is provided in each exhaust chamber. The exhaust chambers D1 to D6 are connected to the first to sixth cell chambers 22a to 22f through the reflux holes h provided in the respective bottom wall portions.

In each of the exhaust chambers of the first lid portion 4 and the second lid portion 5, fluid passage forming wall portions 46 and 56 extending along the other longitudinal inner surface Sb of each exhaust chamber are provided. A third short-direction fluid passage W2 extending in the short-side direction of the exhaust chamber component 400 is formed between the fluid passage-forming wall portions 46, 56 and the longitudinal inner side surface Sb. One end of the third lateral fluid passage W2 opens into the fourth corner portion C4 at a diagonal position of the first corner portion C1, and the other end opens into the second longitudinal fluid passage L2. doing.

In each of the exhaust chambers of the first lid portion 4 and the second lid portion 5, a fluid passage forming wall is provided near the opening at one end of the third lateral fluid passage W2 (near the fourth corner portion C4). First barrier portions 47, 57 integrated with the portions 46, 56 are provided. The first barrier portions 47, 57 project from the fluid passage forming wall portions 46, 56 toward one longitudinal inner surface Sa side of each exhaust chamber, and terminate at a position in front of the one longitudinal inner surface Sa. doing. The first barrier portions 47 and 57 are provided in a state of being integrated with the first lid portion 4 and the second lid portion 5. An electrolytic solution accommodating space A is formed between the first barrier portions 47 and 57 and one of the inner side surfaces Sc in the lateral direction. The terminal positions of the tips of the first barrier portions 47 and 57 are set so that at least a part of the reflux holes h is located in the electrolytic solution accommodating space A.

In each of the exhaust chambers of the first lid portion 4 and the second lid portion 5, one of the longitudinal facing surfaces Sc of each exhaust chamber is located closer to the first barrier portions 47 and 57 than the reflux hole h. Second barrier portions 48, 58 are provided so as to project from the side and extend toward the fluid passage forming wall portions 46, 56 in the electrolytic solution accommodating space A. The barrier portions 48 and 58 are integrally provided with the first lid portion 4 and the second lid portion 5. The second barrier portions 48 and 58 are inclined toward the second corner portion C2 formed between the other longitudinal inner surface Sb of each exhaust chamber and the one lateral inner surface Sc. It is provided. The tips of the second barrier portions 48 and 58 are terminated at a position in front of the fluid passage forming wall portions 46 and 56.

In each of the exhaust chambers of the first lid portion 4 and the second lid portion 5, the second barrier portion 48 is formed from the position in front of the tips of the first barrier portions 47 and 57 along the lateral direction of the exhaust chamber. A first protruding wall portion 47a, 57a projecting to the side of 58, 58 and terminating at a position in front of the second barrier portions 48, 58 is further provided. In each exhaust chamber, a position protruding from the position in front of the tips of the second barrier portions 48, 58 toward the inner side surface Sc side in the lateral direction of each exhaust chamber, and the position in front of the inner surface Sc in the lateral direction of one side. Second protruding wall portions 48a and 58a terminated by are further provided. The first protruding wall portions 47a, 57a and the second protruding wall portions 48a, 58a are integrally provided with the first lid portion 4 and the second lid portion 5.

In the first lid portion 4, the upper surface of the bottom wall portion of each exhaust chamber is gradually lowered from the vicinity of the opening at one end of the third lateral fluid passage W2 toward the reflux hole h. Is sloped. The bottom surface of the first longitudinal fluid passage L1 gradually becomes lower toward the portion where the first and second lateral fluid passages W1a and W1b and the first longitudinal fluid passage L1 meet. It is sloped to go. The bottom surfaces of the first and second lateral fluid passages W1a and W1b are inclined so as to gradually decrease from the first longitudinal fluid passage L1 side toward the second longitudinal fluid passage L2 side. It is attached. The bottom surface of the second longitudinal fluid passage L2 is inclined so as to gradually decrease toward the opening at the other end of the third lateral fluid passage W2 provided in each exhaust chamber. There is. In FIG. 4, the inclination of each of the above parts is indicated by an arrow. Each arrow indicates that the front end side is lower than the rear end side. With such a configuration, the mist of the electrolytic solution discharged from the reflux holes h in each exhaust chamber into each exhaust chamber is collected by the first barrier portions 47, 57, the second barrier portions 48, 58, and the first protruding wall. After touching and liquefying 47a, 57a and the second protruding walls 48a, 58a, it is possible to return to the return hole h of each exhaust chamber along the bottom surface of each exhaust chamber.

As shown in FIG. 5, exhaust ports 65 for opening the centralized exhaust chambers E1 and E2 to the outside are formed at one end and the other end of the second lid portion 5 in the longitudinal direction. Explosion-proof filters 66 are housed in the centralized exhaust chambers E1 and E2. The exhaust gas that has flowed into each centralized exhaust chamber through the first longitudinal fluid passage L1 is discharged to the outside through the explosion-proof filter 66 and the exhaust port 65.

A liquid injection port 60 is formed in the second lid portion 5. The liquid injection port 60 is provided at a position consistent with the return hole h in each exhaust chamber. A screw for attaching a stopper is formed on the inner circumference of the liquid injection port 60.

As shown in FIG. 6, the lid 3 is provided with a welded portion 405 and a positioning rib 406. When the lid 3 is attached to the electric tank 2, the welded portion 405 is welded to the upper end of the partition wall that divides the cell chambers in the electric tank, and together with the partition wall on the electric tank side, forms a wall portion that separates the cell chambers. do. Further, when the welding portion 405 is welded to the upper end of the partition wall between the cell chambers of the electric tank 2, the positioning rib 406 engages with the side surface of the upper end of the partition wall between the cell chambers on the electric tank side and is welded. A positioning rib for positioning the 405 with respect to the partition wall on the battery case side.

(Pole plate group)
FIG. 7 is a perspective view of the electrode plate group (electrode group) 10. As shown in FIG. 7, the electrode plate group 10 includes a plate-shaped negative electrode (negative electrode plate) 11, a plate-shaped positive electrode (positive electrode plate) 12, and a separator arranged between the negative electrode plate 11 and the positive electrode plate 12. 13 and. The electrode plate group 10 has a structure in which a plurality of negative electrode plates 11 and positive electrode plates 12 are alternately laminated in the longitudinal direction of the electric tank 2 via a separator 13. That is, the negative electrode plate 11 and the positive electrode plate 12 are arranged so that their main surfaces extend in the direction perpendicular to the opening surface of the battery case 2. The electrode plate group 10 has a rectangular shape in which the height direction of the electric tank 2 is the lateral direction and the lateral direction of the electric tank 2 is the longitudinal direction when viewed from the stacking direction of the electrode plates.

In the electrode plate group 10, the ears 11a of the plurality of negative electrode plates 11 are collectively welded by the negative electrode side strap 101. Similarly, the ears 12a of the plurality of positive electrode plates 12 are collectively welded by the positive electrode side strap 102. In the lead-acid battery 1, each of the negative electrode side strap 101 and the positive electrode side strap 102 is connected to the negative electrode terminal 8 and the positive electrode terminal 9 via the negative electrode column and the positive electrode column.

As shown in FIG. 7, the negative electrode plate 11 has a current collector (negative electrode current collector) 14 and a negative electrode active material held by the current collector 14, and the negative electrode active material is the negative electrode active material. It constitutes a substance filling portion 15. Further, the positive electrode 12 has a current collector (positive electrode current collector) 16 and a positive electrode active material held by the current collector 16, and the positive electrode active material constitutes a positive electrode active material filling portion 17. doing. In the present embodiment, the negative electrode active material is a negative electrode active material after chemical conversion (for example, in a fully charged state), and the positive electrode active material is a positive electrode active material after chemical conversion (for example, in a fully charged state). When the electrode active material (negative electrode active material and positive electrode active material) is unchemical, the unchemical electrode active material (unchemical negative electrode active material and unchemical positive electrode active material) is the electrode active material (negative electrode active material and negative electrode active material). Contains raw materials for positive electrode active material). In the present specification, the positive electrode plate after chemical conversion from which the positive electrode current collector is removed is referred to as a "positive electrode active material", and the negative electrode plate after chemical conversion from which the negative electrode current collector is removed is referred to as a "negative electrode active material". ..

The separator 13 is formed in a bag shape, and the negative electrode plate 11 is housed therein. On the surface of the separator 13 opposite to the negative electrode plate 11 (the surface on the positive electrode plate 12 side), a plurality of convex ribs 18 extend in the lateral direction of the separator 13 (the lateral direction of the electrode plate group 10). It is formed.

The thickness Y of the electrode plate group 10 described above is not particularly limited, and can be adjusted by the thickness of the electrode plates (negative electrode plate 11 and positive electrode plate 12), the thickness of the separator 13, the distance between the electrode plates, and the like. In the present specification, the thickness Y of the electrode plate group means the thickness of the electrode plate group in a state where the compressive force from the electric tank 2 is not applied to the electrode plate group 10.

A method for measuring the thickness Y of the electrode plate group 10 will be specifically described with reference to FIG. FIG. 8 is a side view of the electrode plate group 10 as viewed from the stacking direction of the electrode plates (negative electrode plate 11 and positive electrode plate 12). The thickness of the electrode plate group 10 is the electrode active material filling portion (negative electrode active material filling portion 15 in FIG. 8) of the electrode plate (negative electrode plate 11 in FIG. 8) on the outermost side of the electrode plate group 10. In a range r of ± 3 mm in the direction shorter than the boundary between the electrode plate and the frame portion located on the ear side of the current collector, one point at the center T1 in the longitudinal direction of the electrode plate group 10 and any arbitrary right side from the center. It is defined as the average value of the thickness of the electrode plate group 10 measured at one point at the position T2 and one point at an arbitrary position T3 on the left side of the center, for a total of three points. However, as shown in FIG. 7, in the case where the separator is arranged on the outermost side of the electrode plate group 10, the height of the rib 18 of the separator is not included in the thickness of the electrode plate group 10. That is, in the case where the separator 13 is arranged on the outermost side of the electrode plate group 10, the thickness of the electrode plate group 10 is measured at the position of the portion (base portion) 19 of the separator 13 that supports the rib 18. The thickness Y of the electrode plate group 10 in the lead-acid battery after chemical conversion is, for example, sufficient for the electrode plate group 10 after chemical conversion to be taken out and washed with water for 1 hour to remove sulfuric acid from the electrode plate group 10 in an oxygen-free system. It can be measured after it has been dried to.

The distance between the negative electrode plate 11 and the positive electrode plate 12 (distance between the electrode plates, distance between the electrodes) adjacent to each other via the separator 13 in the electrode plate group 10 can suppress a decrease in the electrolytic solution more sufficiently and a short circuit can be suppressed. From the viewpoint, it is preferably 0.4 mm or more, more preferably 0.5 mm or more, and further preferably 0.55 mm or more. The distance between the plates is preferably 0.8 mm or less, more preferably 0.75 mm or less, still more preferably 0.7 mm or less, and even more, from the viewpoint of being able to more sufficiently suppress the decrease in the electrolytic solution. It is preferably 0.65 mm or less, and particularly preferably 0.6 mm or less. From these viewpoints, the distance between the plates is preferably 0.4 to 0.8 mm, more preferably 0.4 to 0.75 mm, further preferably 0.5 to 0.7 mm, and further. More preferably, it is 0.55 to 0.65 mm, and particularly preferably 0.55 to 0.6 mm. The distance between the plates means the distance between the plates in a state where the compressive force from the electric tank 2 is not applied to the plate group 10.

When the electrode plate and the separator 13 are in contact with each other, for example, all the separators 13 are extracted from the electrode plate group 10, and for all the extracted separators 13, the upper end of the separator 13 (the end on the ear side in the lateral direction). The thickness of the separator 13 was measured at a position of about 8 mm from the lower end (the end opposite to the selvage side in the lateral direction) (13b in FIG. 7) from the lower end (13a in FIG. 7). , The average value of the measured values can be used as the distance between the plates. When the separator 13 has the rib 18, the thickness of the separator 13 is the sum of the thickness of the base portion 19 and the height of the rib 18. For example, of the plurality of ribs 18 formed in the longitudinal direction of the separator 13, the thickness measured at a total of three points on the two ribs arranged on the outermost side and on the ribs arranged at the midpoints thereof. Let the average value be the thickness of the separator 13. When the separator 13 does not have the rib 18, the thickness measured at a total of three points, one point at the center of the separator 13 in the longitudinal direction, one point at an arbitrary position on the right side of the center, and one point at an arbitrary position on the left side of the center. Let the average value of the values be the thickness of the separator 13. When the separator 13 has a bag shape, the separator 13 is unfolded and the thickness is measured. Further, in the lead-acid battery 1 after chemical conversion, the distance between the plates in the state where no compressive force is applied to the electrode plate group 10 is determined by taking out the electrode plate group 10 from the lead-acid battery 1 after chemical conversion, washing with water for 1 hour, and electrolyzing. The electrode plate group 10 from which the liquid (for example, sulfuric acid) has been removed can be sufficiently dried in a system in the absence of oxygen, and then measured by the above method.

In the lead-acid battery 1 according to the present embodiment, the difference (clearance: XY) between the width X (mm) of the cell chamber 22 and the thickness Y (mm) of the electrode plate group 10 in the battery case 2 is, for example, -1. It may be 1 to 1.2 mm. When the clearance (XY) value is −1.1 mm or more, the decrease in the electrolytic solution can be sufficiently suppressed and the short circuit tends to be suppressed. Further, when the clearance (XY) is 1.2 mm or less, the decrease of the electrolytic solution tends to be sufficiently suppressed. The clearance (XY) is preferably −1.0 mm or more, more preferably −0.6 mm or more, from the viewpoint that the decrease of the electrolytic solution can be more sufficiently suppressed and the short circuit can be further suppressed. The clearance (XY) is preferably 1.0 mm or less, more preferably 0.0 mm or less, and further preferably less than 0.0 mm from the viewpoint of being able to more sufficiently suppress the decrease of the electrolytic solution. From these viewpoints, the clearance (XY) may be -1.0 to 1.0 mm, may be -0.6 to 0.0 mm, and may be -0.6 mm or more and -0.0 mm. It may be less than.

Next, the details of the negative electrode active material, the positive electrode active material, the current collector, and the separator will be described.

(Negative electrode active material)
The negative electrode active material contains at least Pb alone as a Pb component (lead component), _{and further contains a Pb component (for example, PbSO 4} ) other than Pb alone and an additive described later, if necessary. Specifically, the negative electrode active material includes (A) Pb component (hereinafter, also referred to as “(A) component”), (B) lignin sulfonic acid and / or a salt thereof (hereinafter, “(B) component”). Also referred to as) and (C) ^{a carbon material having a specific surface area of 10.0 m 2} / g or less (hereinafter, also referred to as “component (C)”).

[(A) component: Pb component]
Examples of the component (A) include spongy lead and the like. The spongy lead reacts with sulfuric acid in the electrolytic solution and tends to _{gradually change to lead sulfate (PbSO 4).} The negative electrode active material containing the component (A) is obtained by aging and drying a negative electrode active material paste containing a raw material for the negative electrode active material to obtain an unchemicald negative electrode active material, and then chemicalizing the negative electrode active material. be able to. Examples of the raw material for the negative electrode active material include lead powder and the like. As the lead powder, for example, lead powder produced by a ball mill type lead powder manufacturing machine or a barton pot type lead powder manufacturing machine (in a ball mill type lead powder manufacturing machine, a mixture of powder of the main component PbO and scaly metal lead). ). The unchemical negative electrode active material is composed of, for example, basic lead sulfate and metallic lead, and a lower oxide.

The content of the component (A) is 93% by mass or more based on the total mass of the negative electrode active material from the viewpoint of further excellent battery characteristics (battery capacity, discharge characteristics (low temperature and high rate discharge characteristics, etc.), cycle characteristics, etc.). It may be 95% by mass or more, 98% by mass or more, 99% by mass or more, and 99.5% by mass or more. The content of the component (A) may be 99.99% by mass or less, 99.95% by mass or less, and 99.90% by mass or less based on the total mass of the negative electrode active material. good. From these viewpoints, the content of the component (A) is 93 to 99.99% by mass, 93 to 99.95% by mass, 93 to 99.90% by mass, 95 to 99.99% by mass, 95 to 99. It may be 95% by mass, 95 to 99.90% by mass, 98 to 99.99% by mass, 98 to 99.95% by mass or 98 to 99.90% by mass.

[Component (B): lignin sulfonic acid and / or a salt thereof]
Lignin sulfonic acid is a compound in which a part of the decomposition product of lignin is sulfonated, and has a structural unit derived from lignin as a structural unit derived from a phenolic compound, and has a sulfonic acid group. There is. Here, lignin is a polymer compound obtained by oxidatively polymerizing monolignol by an enzyme, and examples of monolignol include p-hydroxysilicate alcohol relatives such as coniferyl alcohol, sinapyl alcohol, and p-coumaryl alcohol. Can be mentioned. The lignin sulfonate is an alkali metal salt of the above-mentioned lignin sulfonic acid and has a sulfonic acid base. Examples of the lignin sulfonate include a sodium lignin sulfonate salt and a potassium lignin sulfonate salt.

The component (B) has, for example, a structure in which a sulfonic acid group or a sulfonic acid base is bonded to a carbon atom at the α-position adjacent to a phenylene group.

The weight average molecular weight of the component (B) is preferably 3000 or more, more preferably 7000 or more, from the viewpoint of suppressing the elution of the component (B) from the negative electrode active material and obtaining excellent DCA performance and cycle characteristics. It is more preferably 8000 or more. The weight average molecular weight of the component (B) is preferably 50,000 or less, more preferably 30,000 or less, still more preferably 20,000 or less, from the viewpoint of excellent dispersibility of the electrode active material. From these viewpoints, the weight average molecular weight of the component (B) may be 3,000 to 50,000, 7,000 to 30,000, and 8,000 to 20,000.

The weight average molecular weight of the component (B) can be measured, for example, by gel permeation chromatography (hereinafter referred to as “GPC”) under the following conditions.
(GPC condition)
Equipment: High Performance Liquid Chromatograph LC-2200 Plus (manufactured by JASCO Corporation)
Pump: PU-2080
Differential refractometer: RI-2031
Detector: Ultraviolet-visible absorptiometer UV-2075 (λ: 254 nm)
Column oven: CO-2065
Columns: TSKgel SuperAW (4000), TSKgel SuperAW (3000), TSKgel SuperAW (2500) (manufactured by Tosoh Corporation)
Column temperature: 40 ° C
Eluent: Methanol solution containing LiBr (10 mM) and triethylamine (200 mM) Flow velocity: 0.6 mL / min Molecular weight Standard sample: Polyethylene glycol (Molecular weight: 1.10 x 10 ⁶ , 5.80 x 10 ⁵ , 2.55 × 10 ⁵ , 1.46 × 10 ⁵ , 1.01 × 10 ⁵ , 4.49 × 10 ⁴ , 2.70 × 10 ⁴ , 2.10 × 10 ⁴ ; manufactured by Toso Co., Ltd., diethylene glycol (molecular weight: 1) .06 × 10 ^2; manufactured by Kishida chemical Co., Ltd.), dibutylhydroxytoluene (molecular weight: 2.20 × 10 ^2; manufactured by Kishida chemical Co., Ltd.)

The content of the component (B) may be 0.05% by mass or more and 0.1% by mass or more based on the total mass of the negative electrode active material from the viewpoint of obtaining excellent cycle characteristics. , 0.15% by mass or more, and may be 0.2% by mass or more. The content of the component (B) may be 0.5% by mass or less and 0.4% by mass or less based on the total mass of the negative electrode active material from the viewpoint of maintaining good liquid reducing performance. , 0.35% by mass or less, and may be 0.3% by mass or less. From these viewpoints, the content of the component (B) is 0.05 to 0.5% by mass, 0.1 to 0.4% by mass, 0.15 to 0.35% by mass, or 0.2 to 0%. It may be 3% by mass.

[(C) component: carbon material]
The component (C) is a carbon material such as carbon black or graphite. Examples of carbon black include furnace black, channel black, acetylene black, thermal black and Ketjen black.

The specific surface area of the component (C) is 10.0 m ² / g or less. In the present embodiment, since the specific surface area of the component (C) is 10.0 m ² / g or less, a sufficient liquid reduction suppressing effect and DCA performance can be obtained. The specific surface area of the component (C) is preferably 7.0 m ² / g or less, more preferably 5.0 m ² / g or less, from the viewpoint of obtaining a sufficient liquid reduction suppressing effect and DCA performance. It is even more preferably 3.0 m ² / g or less, even more preferably 2.0 m ² / g or less, and particularly preferably 1.0 m ² / g or less. The specific surface area of the component (C) is preferably 0.5 m ² / g or more, more preferably 0.7 m ² / g or more, from the viewpoint of obtaining a sufficient liquid reduction suppressing effect and DCA performance. More preferably, it is 0.8 m ² / g or more. From these viewpoints, the specific surface area of component ^{(C), 0.5~10.0m 2 /g,0.5~7.0m 2 /g,0.5~5.0m 2 /g,0.5 ~3.0m 2 /g,0.5~2.0m 2 /g,0.5~1.0m 2 /g,0.7~3.0m 2} /g,0.7~2.0m 2 / ^g, may be 0.7~1.0m ² /g,0.8~2.0m 2 / g or 0.8~1.0m ² / g.

The specific surface area of the component (C) can be measured by, for example, the BET method. The BET method is a method in which an inert gas (for example, nitrogen gas) having a known molecular size is adsorbed on the surface of a measurement sample, and the surface area is obtained from the adsorbed amount and the occupied area of the inert gas. This is a general method for measuring surface area. Specifically, for example, it can be measured under the following conditions.

[Specific surface area measurement conditions]
Equipment: Macsorb Acoustic Surface Area Analyzer (manufactured by Mountain)
Measurement method: BET method Adsorbed gas: Nitrogen Flow rate: 25 mL / min

The content of the component (C) may be 0.2% by mass or more, and 0.5% by mass or more, based on the total mass of the negative electrode active material, from the viewpoint of obtaining sufficient DCA performance and cycle characteristics. It may be 1.0% by mass or more, and may be 1.5% by mass or more. The content of the component (C) may be 3.5% by mass or less, and 3.0% by mass or less, based on the total mass of the negative electrode active material, from the viewpoint of obtaining a sufficient liquid reduction suppressing effect. It may be 2.5% by mass or less, and may be 2.0% by mass or less. From these viewpoints, the content of the component (C) is 0.2 to 3.5% by mass, 0.5 to 3.0% by mass, 1.0 to 2.5% by mass, or 1.5 to 2. It may be 0% by mass.

[Other ingredients]
The negative electrode active material may further contain other components other than the component (A), the component (B) and the component (C). Examples of other components include barium sulfate and short reinforcing fibers. Examples of the reinforcing short fibers include acrylic fibers, polyethylene fibers, polypropylene fibers, polyethylene terephthalate fibers and the like. The content of barium sulfate may be, for example, 0.5% by mass or more and 3.0% by mass or less based on the total mass of the negative electrode active material. The content of the reinforcing short fibers may be, for example, 0.05% by mass or more and 0.3% by mass or less based on the total mass of the negative electrode active material.

(Positive electrode active material)
The positive electrode active material _{contains PbO 2} as a Pb component, and further contains a Pb component other than _{PbO 2 (for example, PbSO 4} ) and an additive described later, if necessary. The positive electrode active material preferably contains β-lead dioxide (β-PbO ₂ ) as a Pb component, and may further contain α-lead dioxide (α-PbO _2). The positive electrode active material can be obtained by aging and drying a positive electrode active material paste containing a raw material for the positive electrode active material to obtain an unchemicald positive electrode active material, and then chemicalizing the positive electrode active material. The raw material for the positive electrode active material is not particularly limited, and examples thereof include lead powder. As the lead powder, for example, lead powder produced by a ball mill type lead powder manufacturing machine or a barton pot type lead powder manufacturing machine (in a ball mill type lead powder manufacturing machine, a mixture of powder of the main component PbO and scaly metal lead). ). _{Lead tan (Pb 3} O ₄ ) may be used as a raw material for the positive electrode active material. The unchemical positive electrode active material preferably contains tribasic lead sulfate as a main component.

The content of the Pb component is preferably 95% by mass or more based on the total mass of the positive electrode active material from the viewpoint of further excellent battery characteristics (capacity, discharge characteristics (low temperature and high rate discharge characteristics, etc.), cycle characteristics, etc.). Yes, more preferably 97% by mass or more, still more preferably 99% by mass or more.

The positive electrode active material may further contain an additive. Examples of the additive include a carbon material (carbon conductive material), short reinforcing fibers and the like. Examples of the carbon material include carbon black and graphite. Examples of carbon black include furnace black (for example, oil furnace black such as Ketjen black (registered trademark)), channel black, acetylene black, and thermal black. Examples of the reinforcing short fibers include acrylic fibers, polyethylene fibers, polypropylene fibers, polyethylene terephthalate fibers and the like.

(Current collector)
The current collector constitutes a conductive path for the current from the electrode active material. Examples of the current collector include a current collector manufactured by a method such as a casting method or an expanding method. Examples of the material of the current collector include a lead-calcium-tin alloy and a lead-antimony alloy. A small amount of selenium, silver, bismuth and the like can be added to these. The current collectors of the positive electrode and the negative electrode may be the same as each other or may be different from each other.

(Separator)
The separator has a function of blocking the electrical connection between the positive electrode and the negative electrode and allowing the sulfate ion of the electrolytic solution to permeate. Examples of the material for forming the separator include polyethylene (PE), polypropylene (PP) and the like. The separator may be a woven fabric, a non-woven fabric, a porous film or the like formed of these materials to which _{inorganic particles such as SiO 2} and Al ₂ O ₃ are attached. The shape of the separator is not particularly limited, and may be, for example, a bag shape, and the positive electrode or the negative electrode plate may be housed in the bag shape separator.

According to the lead-acid battery 1 of the above-described embodiment, both the liquid reduction suppressing performance and the DCA performance can be achieved at the same time. The reason why such an effect is obtained is not clear, but it is caused by the fact that the negative electrode 11 contains lignin sulfonic acid and / or a salt thereof and a carbon material having a ^{specific surface area of 10.0 m 2 / g or less.} Then it is inferred. That is, it is presumed that since the carbon material has the specific specific surface area, lignin sulfonic acid and / or a salt thereof is easily adsorbed on the carbon material, and the carbon material is difficult to be incorporated into the Pb component. Will be done. As a result, it is presumed that the reduction of the hydrogenation voltage due to the carbon material can be suppressed and the high conductivity can be maintained, so that both the suppression performance of the liquid reduction and the DCA performance can be achieved at the same time.

Further, the lead-acid battery 1 of the above embodiment is evaluated according to the EN standard because the negative electrode 11 contains lignin sulfonic acid and / or a salt thereof and ^{a carbon material having a specific surface area of 10.0 m 2 / g or less.} It also has excellent cycle characteristics.

Further, in the lead-acid battery 1 of the above embodiment, the lid 3 is formed between the first lid portion 4, the second lid portion 5, the first lid portion 4, and the second lid portion 5. Exhaust chambers D1 to D6 are provided, and the exhaust chamber retains the mist of the electrolytic solution discharged from each cell chamber 22 in the battery case 2 inside, and the electrolytic solution liquefied in the exhaust chamber is stored in each cell. Since it is configured so that it can be returned to the room, the lead-acid battery 1 of the above-described embodiment can obtain an excellent effect of suppressing liquid reduction.

Further, in the above-mentioned lead storage battery 1, when the gas pressure in the first to sixth cell chambers rises, the gas flowing out from these cell chambers through the recirculation holes h into the first to sixth exhaust chambers is generated. After flowing into the second longitudinal fluid passage L2 through the space in each exhaust chamber and the third lateral fluid passage W2 provided in each exhaust chamber, the first and second lateral fluid passages It flows into the first longitudinal fluid passage L1 through W1a and W1b. The gas flowing into the first longitudinal fluid passage L1 reaches the centralized exhaust chambers E1 and E2, and is discharged to the outside from these centralized exhaust chambers through the exhaust port 65.

The lead-acid battery 1 described above is suitably used as a lead-acid battery for an idling stop system vehicle or a micro-hybrid vehicle. That is, one embodiment of the present invention is an application of the lead-acid battery 1 described above to an idling stop system vehicle or an application to a micro-hybrid vehicle.

<Manufacturing method of lead-acid battery>
The method for manufacturing the lead-acid battery 1 according to the present embodiment is, for example, an electrode plate manufacturing step for obtaining an electrode plate (negative electrode plate 11 and a positive electrode plate 12) and an assembly step for assembling a component including the electrode plate to obtain a lead-acid battery 1. And have.

In the electrode plate manufacturing process, for example, the electrode active material paste (positive electrode active material paste and negative electrode active material paste) is filled in a current collector (for example, a cast lattice body and an expanded lattice body), and then aged and dried. Obtain a non-chemical electrode. The positive electrode active material paste contains, for example, a raw material (lead powder or the like) for the positive electrode active material, and may further contain other additives. The negative electrode active material paste contains a raw material (lead powder or the like), a component (B) and a component (C) of the negative electrode active material, and may further contain the above-mentioned other components.

The positive electrode active material paste can be obtained, for example, by the following method. First, an additive (short fiber for reinforcement, etc.) and water are added to the raw material of the positive electrode active material. Next, dilute sulfuric acid is added and then kneaded to obtain a positive electrode active material paste. _{In producing the positive electrode active material paste, lead tan (Pb 3} O ₄ ) may be used as a raw material for the positive electrode active material from the viewpoint of shortening the chemical conversion time. An unchemicald positive electrode plate can be obtained by filling the current collector with this positive electrode active material paste and then aging and drying it.

The preferred aging conditions for obtaining an unchemical positive electrode plate are 15 to 60 hours in an atmosphere having a temperature of 35 to 85 ° C. and a humidity of 50 to 98 RH%. Preferred drying conditions are at a temperature of 45-80 ° C. for 15-30 hours.

The negative electrode active material paste can be obtained, for example, by the following method. First, a mixture is obtained by adding the component (B), the component (C) and other components (reinforcing short fibers, barium sulfate, etc.) to the raw material of the negative electrode active material and dry-mixing them. Next, a solvent (water such as ion-exchanged water, an organic solvent, etc.) is added to this mixture and kneaded. Then, sulfuric acid (dilute sulfuric acid or the like) is added and kneaded to obtain a negative electrode active material paste. An unchemicald negative electrode plate can be obtained by filling the current collector with this negative electrode active material paste and then aging and drying it.

The preferred aging conditions for obtaining an unmodified negative electrode plate are 15 to 30 hours in an atmosphere having a temperature of 45 to 65 ° C. and a humidity of 70 to 98 RH%. Preferred drying conditions are at a temperature of 45-60 ° C. for 15-30 hours.

In the assembling process, for example, a non-chemical negative electrode plate and a non-chemical positive electrode plate are alternately laminated via a separator 13, and a current collecting portion (ear portion) of an electrode plate having the same polarity is connected by a strap (welding, etc.). To obtain the electrode plate group 10. The electrode plate group 10 is housed in each cell chamber 22 of the electric tank 2, and the negative electrode side strap 101 and the positive electrode side strap 102 of the electrode plate group 10 in the adjacent cell chamber 22 are separated from each other in the cell chamber 22. The lid 3 is attached to the upper end of the battery case 2 after being connected by the inter-cell connection portion penetrating the partition wall 21. Next, an electrolytic solution (dilute sulfuric acid or the like) is injected into each cell chamber 22 from the liquid injection port 60 provided in the second lid portion 5. After injecting the electrolytic solution into each cell chamber, the liquid injection port 60 is closed with a stopper. As a result, an unchemical battery is obtained. Next, a direct current is applied to form an electric tank. The lead storage battery 1 can be obtained by adjusting the specific gravity of the electrolytic solution after chemical conversion to an appropriate specific density.

The chemical conversion conditions and the specific gravity of sulfuric acid can be adjusted according to the properties of the electrode active material. Further, the chemical conversion treatment is not limited to being carried out after the assembly step, and a large number of electrode plates after aging and drying in the electrode plate manufacturing step may be collectively immersed in a chemical conversion tank and carried out (tank chemical conversion).

Although the lead-acid battery of one embodiment of the present invention has been described above, the present invention is not limited to the above-described embodiment.

In the above embodiment, the second lid portion 5 is provided with a liquid injection hole, but the second lid portion 5 is not provided with a liquid injection hole, and after the electrolytic solution is injected, the first lid portion 4 is provided. And the second lid portion 5 may be welded.

In the above embodiment, of the pair of inner side surfaces Sc and Sd in the lateral direction of each exhaust chamber, Sc is defined as the inner surface in one lateral direction and Sd is defined as the inner surface in the other lateral direction. May be the inner surface in the lateral direction of one side and the inner surface in the lateral direction of the other, respectively. Similarly, Sb may be one longitudinal inner surface and Sa may be the other longitudinal inner surface.

In the above embodiment, the return hole h is composed of an aggregate of a plurality of holes, but the return hole h may be composed of a single hole.

Further, the return hole h may be made larger, or the number of holes forming the return hole h may be increased, so that the return hole h also has a function as a ventilation hole.

Further, in the above embodiment, the first protruding wall portions 47a and 57a and the second protruding wall portions 48a and 58a may not be provided.

The lead-acid battery of the above embodiment is a liquid-type lead-acid battery, but the lead-acid battery of the present invention is not limited to this, and may be, for example, a control valve type lead-acid battery, a closed-type lead-acid battery, or the like. As the basic configuration of the lead-acid battery, the same configuration as that of the conventional lead-acid battery can be used.

Hereinafter, the present invention will be specifically described with reference to Examples. However, the present invention is not limited to the following examples.

<Example 1>
(Preparation of electric tank)
An electric tank was prepared in which the upper surface was composed of an open box and the inside was divided into six cell chambers by a partition wall.

(Manufacturing of positive electrode plate)
Acrylic fiber 0.25% by mass (based on the total mass of lead powder) was added to the lead powder as reinforcing short fibers and mixed in a dry manner. Next, 3% by mass of water and 30% by mass of dilute sulfuric acid (specific gravity 1.55) were added to the obtained mixture containing lead powder and kneaded for 1 hour to prepare a positive electrode active material paste. When preparing the positive electrode active material paste, dilute sulfuric acid (specific gravity 1.55) was added stepwise in order to avoid a rapid temperature rise. The blending amount of water and dilute sulfuric acid is based on the total mass of lead powder and reinforcing short fibers.

An expandable current collector produced by expanding a rolled sheet made of a lead alloy was filled with a positive electrode active material paste and then aged in an atmosphere of a temperature of 50 ° C. and a humidity of 98% for 24 hours. Then, it was dried at a temperature of 50 degreeC for 16 hours to prepare a positive electrode plate having an unmodified positive electrode active material.

(Manufacturing of negative electrode plate)
Lead powder was used as a raw material for the negative electrode active material. Mixture of sodium lignin sulfonate (Nippon Paper Industries, Ltd., trade name: Vanillex N), carbon material (specific surface area 0.9 m ² / g graphite), polyethylene terephthalate fiber (cut fiber, fiber length: 3 mm) and barium sulfate Was added to the lead powder and then mixed dry. Next, water was added and then kneaded. Subsequently, dilute sulfuric acid having a specific density of 1.280 was added little by little and kneaded to prepare a negative electrode active material paste. This negative electrode active material paste was filled in an expandable current collector produced by expanding a rolled sheet made of a lead alloy, and then aged in an atmosphere of a temperature of 50 ° C. and a humidity of 98% for 24 hours. Then, it was dried to prepare a negative electrode plate having a non-chemical negative electrode active material. The contents (mass%) of sodium lignin sulfonate, carbon material, polyethylene terephthalate fiber, and barium sulfate based on the total mass of the negative electrode active material after chemical conversion are 0.2% by mass and 1.5, respectively. It was blended so as to be mass%, 0.1% by mass and 1.5% by mass.

(Assembly of battery)
An unchemical negative electrode plate was inserted into a polyethylene separator processed into a bag shape. Next, five unchemical positive electrode plates and six unchemical negative electrode plates inserted into the bag-shaped separator were alternately laminated. Subsequently, the ears of the electrode plates having the same polarity were welded to each other by a cast-on-strap (COS) method to prepare a group of electrode plates. Six groups of these plates were prepared and inserted into an electric tank to assemble an EN standard 12V cell battery (rank performance: 370, size: LN2). At this time, as the lid, a lid having an exhaust chamber of the above-described embodiment shown in FIGS. 4 to 6 was used. Then, a sulfuric acid solution having a specific density of 1.230 was injected, and chemical conversion was carried out at 10.4 A at a constant current for 20 hours. The specific gravity of the electrolytic solution (sulfuric acid solution) after chemical conversion was adjusted to 1.28 (20 ° C.). The clearance (width X of the cell chamber-thickness Y of the electrode plates) was −0.8 mm, and the distance between the plates was 0.75 mm.

In this embodiment, the measurement of the width X of the cell chamber is ± 3 mm shorter than the boundary between the upper peripheral edge of the electrode plate located on the outermost side of the electrode plate group housed in the battery case and the electrode active material filling portion. This was done by measuring the width of the cell chamber in the direction. The thickness Y of the electrode plate group was measured by the following method. First, the electrode plate group was taken out from the battery after chemical conversion and washed with water for 1 hour, and the electrode plate group from which the electrolytic solution was removed was sufficiently dried in a system in the absence of oxygen. Next, a range of ± 3 mm in the short direction from the boundary between the electrode active material filling portion of the negative electrode plate on the outermost side of the electrode plate group and the frame portion located on the ear side of the current collector of the electrode plate r. The thickness of the electrode group is determined by a total of three points: one point at the center T1 in the longitudinal direction of the electrode plate group, one point at an arbitrary position T2 on the right side of the center, and one point at an arbitrary position T3 on the left side of the center. The measurement was performed, and the average value of the measured values was defined as the thickness Y of the electrode plate group.

The distance between the plates was measured by the following method. First, the electrode plate group was taken out from the battery after chemical conversion and washed with water for 1 hour, and the electrode plate group from which the electrolytic solution was removed was sufficiently dried in a system in the absence of oxygen. All separators were then removed from the dried plate group. For all the extracted separators, about 8 mm from the upper end (the end on the ear side in the lateral direction) to the lower end (the end on the opposite side of the ear in the lateral direction). The thickness of the separator was measured, and the average value of the measured values was taken as the distance between the plates. The thickness of the separator is measured at a total of three points on the two ribs arranged on the outermost side in the longitudinal direction and on the ribs arranged at the midpoints of the plurality of ribs formed. The average value of the measured thicknesses was taken as the thickness of the separator.

<Example 2>
A lead-acid battery was produced in the same manner as in Example 1 except that a lid having no exhaust chamber (non-double lid) was used instead of the lid having an exhaust chamber (double lid) as the lid. All the liquid injection ports (all the liquid injection ports corresponding to the cell chambers) of the lid having no exhaust chamber were plugged with a liquid port plug. In addition, the same explosion-proof filter as the double lid was used in the liquid spout.

<Examples 3 to 6>
A lead-acid battery was produced in the same manner as in Example 1 except that graphite having a specific surface area shown in Table 1 was used as the carbon material in place ^{of graphite having a specific surface area of 0.9 m 2 / g.}

<Examples 7 to 10>
Except that the blending amount of each component was adjusted so that the contents (mass%) of sodium lignin sulfonate and carbon material based on the total mass of the negative electrode active material after chemical conversion were the values shown in Table 1. A lead storage battery was produced in the same manner as in Example 1.

<Comparative example 1>
Similar to Example 1 except that a bisphenol resin (condensate of bisphenol, aminobenzenesulfonic acid and formaldehyde, trade name: Vispers P215, manufactured by Nippon Paper Co., Ltd.) was used instead of sodium lignin sulfonate. , A lead-acid battery was manufactured.

<Comparative example 2>
A lead-acid battery was produced in the same manner as in Comparative Example 1 except that a lid having no exhaust chamber (non-double lid) was used instead of the lid having an exhaust chamber as the lid.

<Comparative example 3>
As the carbon material, carbon black (Furness Black, trade name: Vulcan XC72) having a specific surface area of 240 m ² / g was used instead of graphite having a specific surface area of 0.9 m ^{2 / g, and the negative electrode active material after chemical conversion.} The same as in Example 1 except that the blending amount of each component was adjusted so that the content (% by mass) of the sodium lignin sulfonate and the carbon material based on the total mass of the above was the value shown in Table 1. Then, a lead storage battery was manufactured.

<Comparative example 4>
A lead-acid battery was produced in the same manner as in Comparative Example 3 except that a lid having no exhaust chamber (non-double lid) was used instead of the lid having an exhaust chamber as the lid.

<Comparative example 5>
As the carbon material, the same as in Example 1 except that carbon black (acetylene black, trade name: denca black) having a specific surface area of 61 m ^{2 / g was used instead of graphite having a specific surface area of 0.9 m 2 / g.} Then, a lead storage battery was manufactured.

<Comparative Example 6>
Similar to Comparative Example 3 except that a bisphenol resin (condensate of bisphenol, aminobenzenesulfonic acid and formaldehyde, trade name: Vispers P215, manufactured by Nippon Paper Co., Ltd.) was used instead of sodium lignin sulfonate. , A lead-acid battery was manufactured.

<Comparative Example 7>
A lead-acid battery was produced in the same manner as in Comparative Example 6 except that a lid having no exhaust chamber (non-double lid) was used instead of the lid having an exhaust chamber as the lid.

<Characteristic evaluation>
In the following, the DCA performance, life performance (cycle characteristics), and liquid reduction suppressing effect were evaluated for the lead storage batteries of Examples and Comparative Examples. The results are shown in Table 1. The evaluation of each performance was performed by relative evaluation with the measurement result of Comparative Example 7 as 100.

(DCA performance)
DCA performance was evaluated by an evaluation method according to the Dynamic Charge Assessment (DCA) test described in BS EN50342-6: 2015, which is an EN standard. The average current value during charging standardized by the conversion formula is compared, and it is evaluated that the larger the average current value is, the better the DCA performance is. The evaluation criteria are shown below.
A = 110 or more B = 100 or more and less than 110 C = less than 100

(Cycle characteristics (DOD 17.5% life test))
The DOD 17.5% life performance was measured as follows. First, a fully charged lead-acid battery (discharge capacity: 60 Ah, 20-hour rate current: 3 A) was placed in a water tank in which the bath temperature was set to 25 ° C. ± 2 ° C. Then, the following cycle units (a) to (g) were regarded as one cycle, and the following cycle units (a) to (g) were repeatedly carried out in this order.
(A) Discharged at 12 A (corresponding to 4 times the 20-hour rate current) for 2.5 hours. The lower limit voltage for discharge was assumed to be larger than 10.0 V.
(B) The battery was charged at 21 A (corresponding to 7 times the 20-hour rate current) for 40 minutes. The upper limit voltage for charging was 14.4 ± 0.05V.
(C) Discharged at 21 A (corresponding to 7 times the 20-hour rate current) for 30 minutes. The lower limit voltage for discharge was assumed to be larger than 10.0 V.
(D) The above (b) and (c) were alternately repeated 85 times.
(E) The battery was charged at 6 A (corresponding to twice the 20-hour rate current) for 18 hours. The charging method was CC (constant current) -CV (constant voltage) charging, and the voltage during CV charging was 16.0V ± 0.05V.
(F) The capacity of the lead storage battery was confirmed by discharging at 3A (20-hour rate current ± 1.0%) until the discharge end voltage reached 10.5 ± 0.1V.
(G) The battery was charged at 15 A (5 times the 20-hour rate current) for 24 hours. The charging method was CC-CV charging, and the voltage during CV charging was 16.0V ± 0.05V.
This test is a cycle test according to the EN standard, which simulates how lead-acid batteries are used in ISS vehicles. In this test, it was determined that the life was reached when the voltage of the lead-acid battery fell below 10.0 V, and the cycle characteristics were evaluated by comparing the number of cycles until the life was reached. The evaluation criteria are shown below. The results are shown in Table 1.
A = 120 or more B = 110 or more and less than 120 C = 110 or less

(Suppressing effect of liquid reduction)
At an ambient temperature (water tank temperature) of 60 ° C., constant voltage overcharging was performed at 14.4 V for 42 days. By measuring the weight before and after this charging and comparing the weight difference (the amount of liquid reduction due to overcharging (the amount of liquid reduction)), the effect of suppressing the liquid reduction was evaluated. It is evaluated as having an excellent inhibitory effect. The evaluation criteria are shown below.
A = 75 or less B = 75 or more to 85 or less C = 85 or less

1 ... lead-acid battery, 2 ... electric tank, 3 ... lid, 4 ... first lid, 5 ... second lid, 10 ... electrode group (electrode group), 11 ... negative electrode plate (negative electrode), 12 ... Positive electrode plate (positive electrode), 22 ... cell chamber, 400 ... exhaust chamber component, D1, D2, D3, D4, D5, D6 ... exhaust chamber, h ... reflux hole.

Claims (9)

An electric tank with a cell chamber and an open top surface,
The electrode group and the electrolytic solution housed in the cell chamber,
With a lid that closes the opening,
The electrode group has a negative electrode and a positive electrode, and has a negative electrode and a positive electrode.
The negative electrode, possess a Pb component, and lignin sulfonic acid and / or salts thereof, and a carbon material having a specific surface area of not more than 10.0 m 2 / ^g, a negative electrode active material containing,
A liquid lead-acid battery in which the content of the carbon material is 2.0% by mass or less based on the total mass of the negative electrode active material. The liquid lead-acid battery according to claim 1, wherein the content of the lignin sulfonic acid and a salt thereof is 0.05 to 0.5% by mass based on the total mass of the negative electrode active material. The liquid lead-acid battery according to claim 1 or 2, wherein the content of the carbon material is 0.2 % by mass or more based on the total mass of the negative electrode active material. The lid is an exhaust gas formed between a first lid portion, a second lid portion provided on the first lid portion, and the first lid portion and the second lid portion. With a room,
Any one of claims 1 to 3, wherein the bottom wall of the first lid portion that separates the exhaust chamber and the cell chamber is provided with a reflux hole for refluxing the electrolytic solution into the cell chamber. The liquid lead-acid battery described in the section. The liquid lead-acid battery according to any one of claims 1 to 4 , wherein the distance between the adjacent negative electrode and the positive electrode is 0.4 to 0.8 mm. The liquid lead-acid battery according to any one of claims 1 to 5 , wherein the specific surface area of the carbon material is 7.0 m ² / g or less. The liquid lead-acid battery according to any one of claims 1 to 6 , wherein the specific surface area of the carbon material is 1.0 m ² / g or less. An idling stop system vehicle comprising the liquid lead-acid battery according to any one of claims 1 to 7. A micro-hybrid vehicle comprising the liquid lead-acid battery according to any one of claims 1 to 7.

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