JP5877762B2 - Prismatic secondary battery - Google Patents

Description

  The present invention relates to a prismatic secondary battery used for in-vehicle applications.

  In recent years, lithium ion secondary batteries with high energy density have been developed as power sources for electric vehicles and the like. In a square secondary battery for in-vehicle use, a plurality of batteries are connected in series. In order to efficiently produce a large number of batteries, it is necessary to complete the batteries in a short time. For that purpose, it is necessary to inject the electrolyte solution, which is one of the battery manufacturing processes, into the inside of the battery can and to permeate the electrolyte solution into the electrode group housed in the battery can in a short time.

  On the other hand, the inner surface of the portion facing the liquid injection end surface of the electrode group of the battery can is formed in a curved surface, and a space is provided between the facing portion of the battery can and the liquid injection end surface of the electrode group. A technique for providing a mouth in the facing portion is disclosed (Patent Document 1).

JP 2005-251422 A

  In the case of the technique described in Patent Document 1, since a space is provided between the battery can and the liquid injection end surface of the electrode group, the volume of the electrode group that can be stored in the battery can is reduced by the space. There is.

  An object of the present invention is to provide a secondary battery that can be injected in a short time without reducing the volume of an electrode group that can be stored in a battery can.

  The secondary battery of the present invention that solves the above problems includes a wound electrode group that is wound with a separator interposed between a positive electrode plate and a negative electrode plate, and the wound electrode group that is wound around the wound electrode group. A battery can accommodated in a posture in which the direction extends in the lateral direction, and a lid provided with a liquid inlet for sealing an opening opening at an upper portion of the battery can and injecting an electrolyte into the battery can A guide member having an inclined portion that is disposed opposite to the liquid injection port in the battery can and is inclined toward one side in the winding axis direction. Yes.

  According to the present invention, the guide member guides the electrolyte injected from the liquid injection port in the direction along the winding axis direction. Therefore, the end surface of the electrode group in the winding axis direction and the battery can facing the end surface The electrolyte can be actively guided between the inner surface and moved to the bottom of the battery can, and the injection efficiency of the electrolyte can be improved. Therefore, the liquid injection operation can be completed in a short time without reducing the battery capacity, and the productivity of the battery can be improved. Problems, configurations, and effects other than those described above will be clarified by the following description of the embodiments.

1 is an external perspective view of a prismatic secondary battery according to a first embodiment. The external appearance perspective view which shows the state which expand | deployed some winding electrode groups. The exploded perspective view of a battery lid assembly and a winding electrode group. Sectional drawing which shows the state sealed with the injection stopper. Sectional drawing of the square secondary battery concerning 1st Embodiment. FIG. 4 is a cross-sectional perspective view illustrating the configuration of the first embodiment. The perspective view which showed the guide member of 1st Embodiment. The perspective view which showed the protrusion provided in the lid | cover of 1st Embodiment. The perspective view which showed the guide member of 2nd Embodiment. Sectional perspective view explaining the structure of 3rd Embodiment. The perspective view explaining the structure of 3rd Embodiment.

  Hereinafter, with reference to the drawings, each embodiment in which the prismatic secondary battery of the present invention is applied to a prismatic lithium ion secondary battery for a hybrid vehicle will be described.

<First Embodiment>
1 is an external perspective view of the prismatic secondary battery according to the first embodiment, FIG. 2 is an external perspective view showing a state where a part of the wound electrode group is expanded, and FIG. FIG. 4 is an exploded perspective view of the rotating electrode group, FIG. 4 is a cross-sectional view showing a state sealed with an injection stopper, and FIG. 5 is a cross-sectional view of the prismatic secondary battery according to the first embodiment. In the following, for convenience of explanation, the X direction shown in FIG. 1 is referred to as a horizontal direction, the Y direction is referred to as a height direction, and the Z direction is referred to as a thickness direction, but the actual posture state is not limited.

  As shown in FIG. 1, the prismatic secondary battery 10 includes a battery can 1 and a lid 2 that constitute a battery container. The battery can 1 includes a rectangular bottom surface portion PB (see FIG. 5) and a pair of wide surface portions PW that are bent at the long sides of the bottom surface portion PB and face each other in the thickness direction (Z direction). It has a deep-drawn shape having a pair of narrow surface portions PN that are bent at the short side of the bottom surface portion PB and face each other in the lateral direction (X direction). An opening that opens upward in the height direction (Y direction) is formed.

  The lid 2 has a rectangular flat plate shape that closes the opening of the battery can 1. And the positive electrode side terminal structure part 60 and the negative electrode side terminal structure part 70 are provided in the long side direction both sides of the lid | cover 2, and the safety valve 13 and the injection port 12 (FIG. 3) are located in the long side direction center position. Is provided).

  The safety valve 13 is configured to be cleaved and release the gas in the battery can 1 when the internal pressure of the battery can 1 rises above a specified value. The liquid injection port 12 has a preset inner diameter and is formed in the lid 2 so as to be able to inject a predetermined amount of electrolyte into the battery can 1 within a predetermined time. Of the safety valve 13 and the liquid injection port 12, the safety valve 13 is disposed at a substantially central position in the long side direction of the lid 2, and the liquid injection port 12 is displaced to one side in the long side direction of the lid 2 with respect to the safety valve 13. In this embodiment, it is arranged at a position displaced toward the negative electrode side terminal component 70 side. As shown in FIG. 4, the liquid injection port 12 is closed by a liquid injection stopper 11 after the electrolytic solution is injected into the battery can 1. The injection plug 11 is joined to the lid 2 by laser welding or the like to seal the inside of the battery.

  In the battery can 1, a wound electrode group 6 as a power generation element is accommodated. The wound electrode group 6 has a flat wound structure in which the separator 6C, the negative electrode plate 6D, the separator 6C, and the positive electrode plate 6E are wound in a flat state, and curved portions are formed on both sides of the plane portion. Have. A separator 6C is wound around the winding start end portion, and the separator 6C is wound around the winding end end portion several times. In order to prevent unwinding, the separator 6C disposed on the lower side of FIG. The end of the winding is stopped with a tape (not shown) coated with an adhesive on one side in advance.

  In the positive electrode plate 6E, a positive electrode active material mixture containing, for example, a lithium-containing transition metal double oxide such as lithium manganate as a positive electrode active material on both surfaces of an aluminum alloy foil (positive electrode current collector) is substantially uniform and substantially uniform. The exposed portion 6A of the positive electrode metal foil with the positive electrode active material mixture uncoated is formed on one side along the longitudinal direction on both surfaces.

  On the other hand, in the negative electrode plate 6D, a negative electrode active material mixture containing a carbon material such as graphite capable of occluding and releasing lithium ions as a negative electrode active material on both surfaces of a copper alloy foil (negative electrode current collector) is substantially equal and substantially. An exposed portion 6B of the negative electrode metal foil that is not coated with the negative electrode active material mixture is formed on one side along the longitudinal direction on both sides. The separators 6C and 6C are made of a microporous sheet material through which lithium ions can pass. In this example, a polyethylene sheet having a thickness of several tens of μm is used.

  As shown in FIG. 3, the battery lid assembly 40 includes the lid 2, a positive electrode side terminal component 60, and a negative electrode side terminal component 70.

  The positive electrode side terminal component 60 includes a positive electrode external terminal 61, a positive electrode connection terminal 62, a positive electrode terminal plate 63, an insulating plate 64, and a positive electrode current collector plate 21. The positive external terminal 61, the positive terminal plate 63, the positive connection terminal 62, and the positive current collector 21 are integrally fixed and attached to the lid 2.

  The positive electrode side terminal component 60 is produced as follows. In advance, the positive electrode current collecting plate 21 is caulked to the positive electrode connection terminal 62. And the through-hole of the lid | cover 2 and the through-hole of the insulating board 64 are aligned and arrange | positioned. Next, the positive electrode external terminal 61 is fitted into a through hole provided in the positive electrode terminal plate 63 and fixed to the positive electrode terminal plate 63 on the insulating plate 64. The positive external terminal 61 may be crimped to the positive terminal plate 63.

  Then, the positive electrode connection terminal 62 on which the positive electrode current collector plate 21 is crimped is inserted into the through hole of the insulating plate 64 from the back side of the lid 2. The tip end side of the positive electrode connection terminal 62 has a cylindrical shape that is slightly smaller than the through hole of the positive electrode terminal plate 63. By caulking the tip portion of the positive electrode connection terminal 62, the positive electrode side terminal component 60 is The lid 2 is assembled integrally.

  In this state, the positive electrode current collector plate 21, the positive electrode connection terminal 62, the positive electrode terminal plate 63, and the positive electrode external terminal 61 are electrically connected. Further, the positive electrode current collector plate 21, the positive electrode connection terminal 62, the positive electrode terminal plate 63, and the positive electrode external terminal 61 are insulated from the lid 2 by an insulating plate 64.

  The negative electrode side terminal component 70 includes a negative electrode external terminal 71, a negative electrode connection terminal 72, a negative electrode terminal plate 73, an insulating plate 74, and a negative electrode current collector plate 31. The negative electrode side terminal component 70 has the same structure as the positive electrode terminal component 60, and the negative electrode external terminal 71, the negative electrode terminal plate 73, the negative electrode connection terminal 72, and the negative electrode current collector plate 31 are integrally fixed, and the lid 2 is attached.

  In this state, the negative electrode current collector plate 31, the negative electrode connection terminal 72, the negative electrode terminal plate 73, and the negative electrode external terminal 71 are electrically connected. Further, the negative electrode current collector plate 31, the negative electrode connection terminal 72, the negative electrode terminal plate 73, and the negative electrode external terminal 71 are insulated from the lid 2 by an insulating plate 74.

  The prismatic secondary battery 10 is connected to the positive electrode external terminal 61 and the negative electrode external terminal 71 by joining the positive and negative current collecting plates 21 and 31 to the wound electrode group 6. Discharge is possible.

  The positive electrode current collector plate 21 is made of aluminum or an aluminum alloy. The positive electrode current collector plate 21 includes a flat plate-like main body portion 22 attached along the lower surface of the lid 2 and a pair of support portions 22 a bent at approximately 90 ° downward at both ends in the width direction of the main body portion 22. Have. Flat joint pieces 23 are formed at the tips of the pair of support portions 22a. Each joining piece 23 is joined to the wound electrode group 6 by ultrasonic welding. Each of the joining pieces 23 is bent at an angle inclined with respect to the support portion 22a. The pair of joining pieces 23 are inclined so as to be separated from each other in the short side direction of the lid 2 as they move from the central side in the long side direction of the lid 2 toward the outside, and the inclined directions are opposite to each other. Are the same angle with respect to the center plane and are line symmetric. In the pair of joining pieces 23, the positive electrode metal foil exposed portion 6A of the wound electrode group 6 is inserted between them, and the positive electrode metal foil exposed portion 6A of the wound electrode group 6 is opened in a letter C shape. Joined to the foil exposed portion 6A by ultrasonic welding.

  The negative electrode current collecting plate 31 is formed of copper or a copper alloy, but has the same structure as the positive electrode current collecting plate 21. The negative electrode current collecting plate 31 includes a flat plate-like main body portion 32 attached along the lower surface of the lid 2 and a pair of support portions 32a bent at approximately 90 ° downward at both ends in the width direction of the main body portion 32. Have. Flat joint pieces 33 are formed at the ends of the pair of support portions 32a. Each joining piece 33 is joined to the wound electrode group 6 by ultrasonic welding. Each of the joining pieces 33 is bent at an angle inclined with respect to the support portion 32a. The pair of joining pieces 33 are inclined so as to be separated from each other in the short side direction of the lid 2 as it moves from the center side in the long side direction of the lid 2 toward the outside, and the inclination directions are opposite to each other. Are the same angle with respect to the center plane and are line symmetric. In the pair of joining pieces 33, the negative electrode metal foil exposed portion 6B of the wound electrode group 6 is inserted therebetween, and the negative electrode metal foil exposed portion 6B of the wound electrode group 6 is opened in a letter C shape. Joined to the foil exposed portion 6B by ultrasonic welding.

  Then, the wound electrode group 6 is accommodated in the battery can 1 in a posture extending in the lateral direction so that the winding axis direction of the wound electrode group 6 is parallel to the opening of the battery can 1, and thereafter Then, the opening of the battery can 1 is closed with the lid 2, and the fitting portion between the battery can 1 and the lid 2 is welded and sealed with a laser.

  The distance between the pair of wide surface portions PW of the battery can 1 is set to a dimension such that the inner surface of each wide surface portion PW is in contact with the flat portion of the wound electrode group 6 via an insulating film sheet (not shown). ing. And the space | interval of a pair of narrow surface part PN is set to the dimension which has a predetermined gap between the end surfaces of the winding electrode direction 6 on both sides in the winding axis direction.

  The wound electrode group 6 is accommodated in the battery can 1 via an insulating film sheet (not shown). In the state where the wound electrode group 6 is housed in the battery can 1, the planar portion of the wound electrode group 6 contacts the inner surfaces of the pair of wide surface portions PW of the battery can 1. And between the end surface of the winding electrode direction both sides of the winding electrode group 6, and the inner surface of the narrow surface part PN of the battery can 1 facing the end surface, it extends in the height direction (Y direction) of the battery can 1. Existing gaps are formed.

  The wound electrode group 6 needs to infiltrate the electrolyte into the wound electrode group 6 from the end surfaces on both sides in the wound axis direction. Therefore, a predetermined gap is always provided between the end surfaces of the wound electrode group 6 on both sides in the winding axis direction and the inner surface of the battery can 1 facing the end surfaces, that is, the inner surface of the narrow surface portion PN. The bottom surface portion PB of the battery can has a planar shape, and is divided into a short side direction and extends in the long side direction between the curved portion on the bottom side of the wound electrode group 6. A part is formed.

  The prismatic secondary battery 10 has a guide member 80 as shown in FIG. As shown in FIGS. 5 and 6, the guide member 80 is disposed on the inside of the can of the liquid injection port 12.

  The guide member 80 has an inclined portion 82 that is opposed to the liquid injection port 12 in the battery can 1 and is inclined toward one side in the winding axis direction. The guide member 80 can guide the electrolyte injected from the liquid injection port 12 in the direction along the winding axis direction by the inclined surface 82. The guide member 80 is configured by a block-shaped member having a predetermined plate thickness that can be disposed in a space between the back surface of the lid 2 and the upper end portion of the wound electrode group 6. The guide member 80 has an attachment surface 83 that is attached to the lower surface of the lid 2 and a recess 81 that is recessed at the center of the attachment surface 83. The concave portion 81 is continuous with the liquid injection port 12 on the mounting surface 83 side, and is open only on one side surface 80a of the four side surfaces except for the mounting surface 83 to the lid 2. An inclined portion 82 is formed on the bottom surface of the recess 81 so as to gradually move toward the side surface 80a as it moves downward. The inclined part 82 has a flat surface.

  As shown in FIG. 6, the guide member 80 has a side surface 80 a facing the negative electrode side short side 4, which is one side in the winding axis direction of the wound electrode group 6, at a position facing the lower side of the liquid injection port 12. It is attached. The recess 81 forms a passage portion of the guide member 80.

  Since the safety valve 13 is often arranged at the center in the long side direction of the lid 2, the liquid injection port 12 is arranged to be biased toward one short side of the lid 2. For example, as shown in FIG. 3, when the liquid injection port 12 is installed at a position closer to the short side 4 on the negative electrode side than the short side 3 on the positive electrode side of the lid 2, The guide member 80 is installed so that the electrolyte flows toward the short side 4 along the rotational axis direction.

  Since the recess 81 is open only on the side surface 80a toward the negative electrode side short side 4 side, the electrolytic solution injected into the battery can 1 through the injection port 12 is supplied to the wound electrode group by the inclined portion 82. It can guide so that it may flow toward the negative electrode side short side 4 side along 6 winding axis directions.

  As shown in FIG. 7, the fitting surface 83 of the guide member 80 is provided with four fitting holes 84 at the four corners. The lid 2 is provided with four protrusions 85 as shown in FIG. The four protrusions 85 provided on the lid 2 are provided so as to coincide with the positions of the four fitting holes 84 of the guide member 80. Further, the protrusion 85 has a cylindrical shape, and the diameter thereof is set to be slightly larger than the diameter of the fitting hole 84 of the guide member 80. By setting the dimensions as described above, the guide member 80 is press-fitted into the protrusion 85 of the lid 2 and fixed.

  In addition, as a method of fixing the guide member 80 to the lid 2, adhesion can be used. At the time of bonding, the diameter of the fitting hole 84 provided in the guide member 80 is made slightly larger than the protrusion 85 of the lid 2, contrary to the above press-fitting. The guide member 80 can be fixed to the lid 2 with an adhesive by applying an adhesive to the engaging surfaces of the protrusions 85 and the fitting holes 84. The guide member 80 is made of an insulator and is preferably made of resin.

  When the guide member 80 is press-fitted into the lid 2, foreign matter may be generated due to friction between the fitting hole 84 of the guide member 80 and the protrusion 85 of the lid 2. When the guide member 80 is made of metal, metal is generated as a foreign matter. By making the guide member 80 made of resin, even if a foreign matter is generated by friction with the projection 85 of the lid 2, a resin having a lower strength than the metallic projection is generated as the foreign matter.

  If the metal foreign matter is in the battery, it causes a short circuit between the positive electrode and the negative electrode, but if it is a resin, it does not cause a short circuit between the positive electrode and the negative electrode. Further, the guide member 80 may be detached from the lid 2 when vibration or impact is applied to the battery. At that time, if the guide member 80 is made of resin, the positive electrode and the negative electrode are not short-circuited even if the guide member 80 moves freely in the battery.

  Conventionally, when an electrolytic solution is injected into the battery can 1 from the injection port 12, the space directly hits the upper surface of the wound electrode group 6 and is surrounded by the upper curved portion of the wound electrode group 6 and the pair of wide surface portions. And then started to flow toward the positive side short side 3 side and the negative side short side 4 side, which are one side and the other side in the winding axis direction.

  In order to improve the injection efficiency and shorten the injection time, it is necessary to allow the electrolyte injected from the injection port 12 to reach the bottom of the battery can 1 in a shorter time.

  Therefore, in the present embodiment, the guide member 80 is disposed inside the can of the liquid injection port 12, and the electrolyte injected from the liquid injection port 12 is brought into contact with the inclined portion 82 so as to follow the winding axis direction. And it was set as the structure guided so that it might flow toward the negative electrode side short side 4 side nearer to the injection hole 12. Thus, the gap extending in the height direction between the negative electrode side end surface which is one side of the winding electrode group 6 in the winding axis direction and the narrow surface portion PN of the battery can 1 facing the negative electrode side end surface. The electrolyte can be actively guided to the surface. A gap extending in the height direction is formed between the end face on the positive electrode side that is the other side in the winding axis direction of the wound electrode group 6 and the narrow surface portion PN of the battery can 1 facing the end face on the positive electrode side. It can be an air exhaust passage.

  Therefore, the electrolytic solution can flow from the upper part of the battery can 1 to the can bottom of the battery can 1 and can be quickly stored in the can bottom. And the liquid level height of the electrolyte solution stored in the battery can can be reached in a shorter time to a position higher than the lower ends of the end faces on both sides of the winding electrode group 6 in the winding axis direction. The time for allowing the electrolytic solution to permeate into the rotating electrode group 6 can be further shortened, the injection efficiency of the electrolytic solution can be improved, and the injection time can be shortened. Therefore, the liquid injection operation can be completed in a short time without reducing the battery capacity, and the productivity of the battery can be improved.

  In the present embodiment, the electrolyte injected into the battery can 1 from the injection port 12 is disposed on the negative short side 4 side closer to the injection port 12 along the winding axis direction of the wound electrode group 6. However, the electrolyte is applied between the end surface in the winding axis direction of the wound electrode group 6 and the inner surface of the narrow surface portion PN of the battery can 1 facing the end surface. As long as the electrolyte can be actively guided to the gap extending in the height direction. Therefore, the guide member 80 may be configured to guide it so as to flow toward the positive-side short side 3 side, which is the other side in the winding axis direction, and also on the positive-side short side 3 side and the negative-side short side 4 side. It is good also as a structure guided so that it may flow toward both.

Second Embodiment
Next, a second embodiment will be described with reference to FIG. Note that the same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  What is characteristic in this embodiment is that the guide member 180 has a flat surface 182 parallel to the lid 2 and is inclined so that the groove depth gradually increases as the inclined portion is shifted to one side in the winding axis direction. It is that it was set as the recessed groove-shaped hollow 86 which was made.

  The guide member 180 has a recess 181 that is recessed in the center of the mounting surface 83. The concave portion 181 is continuous with the liquid injection port 12 on the mounting surface 83 side, and is open only on one side surface 80a of the four side surfaces except for the mounting surface 83 to the lid 2. The recess 181 forms a passage portion of the guide member 180.

  The recess 181 has a flat surface 182 disposed in parallel to the lid 2 and a recess (inclined portion) 86 provided at the center of the flat surface 182. The recess 86 has a concave groove shape that is inclined so that the depth of the groove gradually increases from the central portion of the flat surface 182 toward the side surface 80 a, and the electrolyte is supplied in the winding axis direction of the wound electrode group 6. Along the negative electrode side short side 4 side.

  The recess 86 can concentrate the electrolyte in the center in the recess 181 and can flow the electrolyte at a higher speed. Therefore, in the gap extending in the height direction between the negative electrode side end surface which is one side of the winding electrode group 6 in the winding axis direction and the narrow surface portion PN of the battery can 1 facing the negative electrode end surface. The electrolytic solution can be positively guided, and the electrolytic solution can be quickly accumulated on the bottom of the battery can 1 to improve the injection efficiency of the electrolytic solution.

<Third Embodiment>
Next, a third embodiment will be described below with reference to FIGS. Note that the same components as those in the above-described embodiments are given the same reference numerals, and detailed description thereof is omitted.

  What is characteristic in the present embodiment is that the guide member 280 is formed integrally with the lid 2.

  The guide member 280 is formed integrally with the lid 2 and extends downward from the liquid injection port 12 and opens toward the negative electrode side terminal component 70 side. It has an inclined part 282 that gradually moves toward the negative electrode side terminal constituting part 70 side as it moves downward at the lower end of the vertical wall part 281. A passage portion of the guide member 280 is formed by the vertical wall portion 281 and the inclined portion 282.

  The inclined portion 282 is inclined toward the opening from which the electrolyte flows into the battery can 1. This inclination is directed toward the bottom of the battery can 1. Therefore, the electrolytic solution injected from the liquid injection port 12 can be actively guided to the gap between the wound electrode group 6 and the narrow surface portion PN of the battery can 1, and the electrolytic solution can be introduced into the can of the battery can 1. Accumulated in the bottom can improve the efficiency of electrolyte injection.

  The guide member 280 is provided not only on the entire liquid injection port 12 but only on a portion corresponding to a part thereof. The guide member 280 can be manufactured integrally with the lid 2 by, for example, press-molding the lid 2. Therefore, the material cost can be reduced, and the cost of the battery can be reduced by reducing the number of assembly steps.

  Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above-described embodiments, and various designs can be made without departing from the spirit of the present invention described in the claims. It can be changed. For example, the above-described embodiment has been described in detail for easy understanding of the present invention, and is not necessarily limited to one having all the configurations described. Further, a part of the configuration of an embodiment can be replaced with the configuration of another embodiment, and the configuration of another embodiment can be added to the configuration of an embodiment. Furthermore, it is possible to add, delete, and replace other configurations for a part of the configuration of each embodiment.

1 Battery can
2 Lid 3 Positive side short side 4 Negative side short side 6 Winding electrode group 6A Positive electrode metal foil exposed part 6B Negative metal foil exposed part 6C Separator 6D Negative electrode plate 6E Positive electrode plate 10 Rectangular secondary battery 11 Injection plug 12 Injection port 13 Safety valve 21 Positive electrode side current collector plate 31 Negative electrode side current collector plate 40 Battery lid assembly 60 Positive electrode side terminal component part 70 Negative electrode side terminal component part 80, 180, 280 Guide member 80a Side surface 81, 181 Concave part 82 Inclined part 83 Mounting surface 84 Mating hole 85 Projection 86 Recess (Inclined part)
182 Flat surface 281 Vertical wall portion 282 Inclined portion

Claims (4)

A wound electrode group in which a positive electrode plate and a negative electrode plate are wound with a separator interposed therebetween, and the wound electrode group is accommodated in a posture state in which a winding axis direction of the wound electrode group extends in a lateral direction. A prismatic secondary battery having a battery can and a lid provided with a liquid inlet that seals an opening that opens at the top of the battery can and injects an electrolyte into the battery can,
In the battery can, the guide member is disposed so as to face the liquid injection port and has an inclined portion inclined toward one side of the winding axis direction ,
The lid is made of a metal material, and the guide member is integrally formed with the prismatic secondary battery.   The prismatic secondary battery according to claim 1, wherein the inclined portion of the guide member is a flat surface.   The guide member has a flat surface parallel to the lid, and the inclined portion is a concave groove-shaped recess that is inclined so that the groove depth gradually increases as it moves to one side in the winding axis direction. The prismatic secondary battery according to claim 1.   2. The prismatic secondary battery according to claim 1, wherein the liquid injection port has an opening formed at a position displaced to one side in a winding axis direction with respect to the wound electrode group.

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