JP4075339B2 - Battery and manufacturing method thereof - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a battery excellent in productivity and a method for manufacturing the same.
[0002]
[Prior art]
In recent years, high-performance secondary batteries have been actively developed as clean energy sources for notebook computers, small portable devices, and automobiles. The secondary battery used here is required to have excellent productivity with a high yield and a high capacity and high output while being small and lightweight.
[0003]
An electrode having a projecting portion made of a current collector not coated with an electrode active material layer projecting from an electrode body and a separator in a direction opposite to each other along the winding axis direction of the positive electrode and the negative electrode It is known that sometimes it is not necessary to connect a large number of tabs, so that it can be manufactured without reducing the productivity, and the electric resistance can be reduced when collecting current from the electrodes, so that high output can be exhibited.
[0004]
As a method for collecting current from the projecting portion projecting from the electrode body to the battery terminal, it is preferable to weld the projecting portion to the current collecting electrode, but the current collector is extremely thin and difficult to weld as it is. After the protrusions were stacked and the thickness was increased (thickened), the current collecting electrode was further stacked and welded to the overlapped portion (thickened portion).
[0005]
However, in this method, in order to secure a certain area of the junction between the current collecting electrode and the protruding portion, the size of the protruding portion that is the protruding portion from the electrode body (the portion that does not contribute to the battery reaction) should be less than a certain level. It cannot be reduced, and the energy volume density of the battery decreases. Therefore, in Japanese Patent Application Laid-Open No. 10-261441, in order to ensure bonding, a protruding portion overlapped with a constricted portion of a collecting electrode having a constricted portion provided with a slit at the apex is inserted, and a slit in the constricted portion is inserted. Discloses a method of joining the protrusion and the collecting electrode by laser welding.
[0006]
[Problems to be solved by the invention]
However, the method disclosed in Japanese Patent Laid-Open No. 10-261441 has been difficult to say that the productivity is high. That is, when inserting the protruding portion of the current collector into the constricted portion of the current collecting electrode, a general current collector is made of a metal foil. The protrusion of the current collector is not inserted, and thus the protrusion that is not inserted is not welded to the current collecting electrode, so that the weldability is not improved and the insertion process is troublesome.
[0007]
Therefore, this invention makes it the subject which should be solved to provide the battery which can weld-join a collector electrode from the protrusion direction of a protrusion part with high productivity, and its manufacturing method, when joining a protrusion part and a collector electrode. .
[0008]
[Means for Solving the Problems]
  In order to solve the above problems, the present inventors have conducted intensive research.As a result, the present invention has a positive and negative electrode plate and a separator, and at least one of the positive and negative electrode plates has an edge portion of the electrode plate. A battery comprising a flat electrode body having a protruding portion protruding from an edge of the other electrode plate, wherein the positive and negative electrode plates are wound or laminated via the separator, At least part of an end face of the electrode body and theFormed by windingFlat minor axis directionAlternatively, they are arranged along the flat width direction which is the same as the laminating direction of the flat shape formed by stacking.A collector electrode having a size covering a projecting tip of the plurality of projecting portions, the collector electrode being in the minor axis direction of the electrode body;Or the short width directionInvented a battery and a method for manufacturing the same, wherein the current collector electrode is joined to the projecting portion of the electrode body via the peripheral edge of the groove portion.
[0009]
  That is, the electrode body has a flat shape, and the current collecting electrode is at least a part of the end surface and is formed by the flat shape in the minor axis direction of the wound shape or the flat shape of the laminated shape formed by the lamination. The junction region between the collecting electrode and the projecting tip of the projecting portion of the electrode body is set to a size that covers the projecting tip of the projecting portions arranged along the short width direction of the flat shape that is the same direction as the direction In addition, a groove portion is arranged along the short diameter direction or the short width direction of the flat electrode body with respect to the collecting electrode, and the collecting electrode is connected to the protruding tip of the electrode body at the peripheral portion of the groove portion. Therefore, it is not necessary to insert the protruding portion into the slit of the constricted portion of the current collecting electrode as in the prior art, and therefore the current collecting electrode can be reliably bonded to the protruding portion. In addition, the flat shape of the electrode body and the direction of the groove portion of the current collecting electrode are combined, and the direction of the groove portion bridges the short diameter direction or the short width direction of the flat shape of the electrode body even if the bonding distance is short. Since it corresponds to the direction (direction across the flat shape), the bonding strength of the collecting electrode to the electrode body is improved.
(A) About the battery of the present invention
(A-1) In addition to the above configuration, the current collecting electrode has an end surface on the side where the protruding portion of the electrode body protrudes, along the direction perpendicular to the short diameter direction or the short width direction. The current collecting electrode is joined to the projecting portion of the electrode at the corrugated portion.
(A-2) Moreover, it replaces with the structure of (a-1), and the said collector electrode has another groove part arrange | positioned in the direction which cross | intersects with respect to the said groove part, This other groove part The current collecting electrode is joined to the projecting portion of the electrode body within a range surrounded by the groove portion.
(A-3) Further, instead of the configuration of (a-1), the current collecting electrode is provided with a shape that covers the entire protruding tip of the protruding portion.
(B) About the manufacturing method of the battery of this invention
(B-1) In addition to the above configuration, the welding step is a step of heating the current collecting electrode while cooling the protruding portion.
(B-2) And, instead of the configuration of (b-1), the heating method in the welding process is arc discharge performed from the opposite side to the protruding portion while blowing an inert gas. To do.
(B-3) Further, instead of the configuration of (b-1), the portion of the current collecting electrode that is in contact with the protruding tip of the protruding portion is heated and melted so as to cover the protruding tip. It is characterized by that.
(B-4) Furthermore, it replaces with the structure of (b-1), and the said welding process is a process performed in inert atmosphere, It is characterized by the above-mentioned.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the battery of the present invention and the manufacturing method thereof will be described in detail.
[0011]
[Battery configuration]
The battery of the present invention has an electrode body in which a positive and negative electrode plate and a separator are laminated or wound. Although the structure of the positive and negative electrode plates is not particularly limited, an electrode plate coated with an electrode active material is preferable on the surface of the current collector, and further, there is a portion where the electrode active material is not coated on the protruding portion of the electrode plate described later. An electrode plate is preferred. The battery to which the present invention can be applied includes an electric double layer capacitor in addition to a general battery such as a lithium secondary battery, a nickel hydrogen battery, and a nickel cadmium battery. As the positive electrode plate, the negative electrode plate, and the separator forming the electrode body, members used for the positive electrode, the negative electrode, and the separator corresponding to the type of battery can be used.
[0012]
  The electrode body is formed by stacking a plurality of sets of a winding type in which a belt-like positive and negative electrode plate and a belt-like separator sandwiched between positive and negative electrode plates are wound, and a separator sandwiched between the positive and negative electrode plates and the positive and negative electrode plates And laminated type. In order to improve volumetric efficiency, the wound electrode body, FlatUse a flat shape. And an electrode body has the protrusion part which protruded the edge part of the at least one electrode plate from the edge part of the other electrode plate among positive / negative electrode plates. A collecting electrode is welded to the protruding portion. A battery terminal is electrically connected to the current collecting electrode. In addition, it is not necessary that the end edge part of the electrode plate protrudes as a protruding part, and a protruding part from which a part of the electrode plate protrudes may be used.
[0013]
The current collecting electrode is a member that takes out the electric power generated in the electrode of the electrode body by being joined to the projecting tip of the projecting portion of the electrode body. The current collector electrode is joined to the protruding tip of the protruding portion, whereby the length of the protruding portion can be shortened. As a result, the axial length of the electrode body can be shortened, and the battery having this electrode body can be miniaturized.
[0014]
  When the collector electrode is joined to the electrode body,Formed by windingFlat minor axis directionAlternatively, a flat-shaped short width direction that is the same direction as the laminating direction of the flat shape formed by stackingHas a groove portion arranged along the. Since the groove portion is arranged along the minor axis direction or the short width direction of the electrode body, the groove portion has a peripheral edge portion of the groove portion intersecting with the projecting tip of the projecting portion of the electrode body. The current collecting electrode is joined to the protruding tip of the protruding portion of the electrode body through the peripheral edge of the groove. The shape of the groove may be any shape such as a rectangle (strip shape) or a circle.
[0015]
As a specific bonding method, the current collecting electrode and the plurality of protruding portions are bonded together by heating and melting the peripheral portion of the groove portion of the collecting electrode while being in contact with the direction of the protruding tip of the electrode body. It is preferable because it is possible. As a method for heating and melting, general welding can be exemplified. In the case of joining by welding, in addition to the method of melting and joining the peripheral portion of the groove portion regardless of the presence or absence of the protruding tip, a method of melting only the portion in contact with the protruding tip of the peripheral portion can be adopted. .
[0016]
The current collecting electrode and the protruding tip may be joined not only by one groove part, but also by arranging a plurality of groove parts and joining them by a plurality of groove parts. When a plurality of groove portions are provided, the number of joint portions increases, so that the joint strength can be improved and the internal resistance of the battery can be reduced. When there are a plurality of groove portions, the electrodes are strongly bonded to each other and the electrode plates to the current collecting electrode. In other words, the presence of multiple grooves can increase the number of junctions between the electrodes and between the collector electrode and the electrode, preventing excessive stress from concentrating at the junctions, and also presenting multiple junctions in the grooves. As a result, when a large current is taken out from the electrode body, the current flowing per groove can be reduced, and the internal resistance of the battery can be reduced and overheating damage due to the large current in the groove can be prevented.
[0017]
  The mode of joining and the size (length) of the groove are not particularly limited, so that as many projecting tips and current collecting electrodes as possible can be joined, and the current collector electrode and the projecting tip are joined with a short diameter of the electrode body. directionOr short width directionIt is preferable that the groove is bonded to the electrode body for a long time.Or short width directionIt is preferable to be long. The minor axis direction of the electrode bodyOr short width directionWhen the current collecting electrode is joined along the line, the joined portions between the current collecting electrode and the protruding tip can be dispersed, and the current flowing through the positive and negative electrode plates can be made uniform.
[0018]
  Furthermore, the minor axis direction of the electrode bodyOr short width directionIt is more effective to join all the protruding tips along the line and the current collecting electrode. In addition, when there are a plurality of groove portions as described above, the plurality of groove portions as a whole in the minor axis direction of the electrode bodyOr short width directionIt may be joined to all of the protruding tips. For example, a plurality of groove portions can be formed so as to face each other.
[0019]
Furthermore, when the current collector electrode and the protruding tip are joined by welding, the current collector electrode has another groove portion arranged in a direction intersecting the groove portion, and is surrounded by the other groove portion and the groove portion. It is preferable that the peripheral edge within the range is melted and joined to the protruding tip. This is because the current collecting electrode is partitioned by the other groove portion, so that the heat conduction by welding is cut off and the heat can be effectively used.
[0020]
The shape of the current collecting electrode is not particularly limited, but is preferably a plate-like body. The size of the current collecting electrode is not particularly limited. Any size that can cover at least a part of the end face of the electrode body is acceptable. For example, it can be about half the size of the end face of the electrode body, and can cover almost the entire protruding tip of the end face. Among these, it is preferable that the size and shape cover almost the entire protruding tip. This is because by increasing the area of the current collecting electrode as much as possible, the area where the welded portion to be joined to the projecting tip can be increased, the stability of joining can be improved, and the internal resistance of the battery can be reduced.
[0021]
  Furthermore, the shape of the current collecting electrode is preferably a waveform. This is because, when the current collecting electrode is corrugated, when the current collecting electrode comes into contact with the projecting tip of the projecting portion of the electrode body, the projecting tip converges on the waveform portion of the current collecting electrode. Therefore, the wave line of the collecting electrode isA direction perpendicular to the minor axis direction or the minor width direction on the end surface on which the projecting portion projectsIt is preferable to form along. Since the shape of the electrode body is a flat shape, the arrangement direction of the protruding portions has a straight portion, so that the wave streaks are also made linear accordingly. The number of wave lines provided on the current collecting electrode is not limited, but about two is preferable from the viewpoint of workability. Further, the top (valley) portion of the waveform may be sharp or rounded.
[0022]
  The protruding part of the part joined to the collector electrode of the electrode body is the minor axis directionOr short width directionIt is preferable to have a thickened portion superimposed on each other. The minor axis direction of the thickened partOr short width directionThe state where the protrusions are overlapped indicates that the protrusions are overlapped, and may be an integrated state or a state compressed in a stacked state. In other words, by making the multiple protrusions thicker, the difference in thickness compared to the collector electrode is reduced, so that the weldability between the collector electrode and the protrusion is improved and the joint strength is improved. To do.
[0023]
  The protrusion preferably has a plurality of thickened portions. Multiple thickened parts are the minor axis direction of the protruding partsOr short width direction5 shows that a plurality of thickened portions where the protruding portions are overlapped are formed. Since the protruding portion has a plurality of thickened portions, the length of the protruding portion can be shortened. When a plurality of thickening portions are provided, it is preferable that the current collecting electrodes have a corrugated shape and are joined to the corrugated portion in a plurality of pairs, more preferably in pairs. This is because more reliable joining can be performed with fewer joining sites.
[0024]
The current collecting electrodes are preferably formed of the same material as the protrusions to be joined. By forming the current collecting electrode and the protruding portion from the same material, it is possible to suppress the occurrence of electrical contact when used as a battery. That is, when the current collecting electrode and the protruding portion are made of different materials, electric contact is generated due to a potential difference. Moreover, it is because welding between the same kind of materials is easier.
[0025]
  Although it does not specifically limit as another structure of a battery, It has general components, such as a battery terminal, the battery case which accommodates an electrode body, electrolyte solution, and a safety device.
The battery of the present embodiment has the above-described configuration and at least one of the following components (a-1) to (a-3) as an essential requirement. The components (a-1) to (a-3) described below are the same as those described above as optional components.
(A-1) A waveform in which a wave streak extends along the minor axis direction or the direction orthogonal to the minor width direction on the end surface of the electrode body on the side where the projecting portion of the electrode body projects. The current collecting electrode is joined to the projecting portion of the electrode at the corrugated portion.
(A-2) The current collecting electrode has another groove portion arranged in a direction intersecting with the groove portion, and is within the range surrounded by the other groove portion and the groove portion. A collecting electrode is joined to the protruding portion of the electrode body.
(A-3) The current collecting electrode has a shape that covers the entire protruding tip of the protruding portion.
[0026]
[Battery Manufacturing Method]
The battery manufacturing method of the present invention is a method for manufacturing the above-described battery. Therefore, since the configuration is the same as that of the battery described above, further explanation is omitted here.
[0027]
The battery manufacturing method of the present invention includes a contact process and a welding process.
[0028]
The abutting step is a step of bringing the collecting electrode into contact with the protruding tip of the protruding portion of the electrode body described above. In the abutting step, the current collecting electrode need only be brought into contact with the protruding tip of the electrode body, so that the deformation of the protruding portion hardly occurs and the productivity is high.
[0029]
  If the shape of the collector electrode is a waveform,Major axis directionIt is preferable that the current collecting electrode is brought into contact with each other and the protruding tip is converged to the waveform portion of the current collecting electrode. Furthermore, when the projecting tip is brought into contact with the current collecting electrode, it is preferable from the viewpoint of improving productivity that the plurality of projecting portions are collectively thickened in advance. For example, a comb-like jig can be inserted and divided between every predetermined number of protruding portions, and the protruding tip can be brought into contact with the current collecting electrode while holding the predetermined number of protruding portions with a jig or the like. .
[0030]
In the welding process, heating is performed from the collecting electrode side until at least a part of the peripheral portion of the groove portion of the collecting electrode that is in contact with the protruding portion is melted. As a result of the melting of the peripheral portion, the projecting tip is melted by the heat transfer, and the peripheral portion of the groove portion of the collecting electrode and the protruding portion are welded. In that case, since the electrode body has a large heat capacity, the protruding portion melts from the protruding tip. Therefore, it is possible to melt and weld only the protruding tip by controlling the heating time of the collecting electrode.
[0031]
More specifically, when the collecting electrode is melted by the welding process and the melt is supplied to the projecting tips of the projecting portions, the melt enters the interfaces of the projecting portions, and the heat melts each projecting tip. And the melts of each other are mixed. Thereafter, when the melt is cooled, the melt is solidified to form a welded portion in which both are integrally formed, and the current collecting electrode and the electrode body are joined. Here, the supply of the melt at the peripheral edge to the protruding portion can be performed by capillary action due to the interface of the protruding portion, or by moving the collector electrode above the protruding tip and using gravity. Furthermore, from the viewpoint of bonding reliability, heating is performed until the portion of the peripheral edge of the current collecting electrode that contacts the protruding tip of the protruding portion is heated and melted to cover the protruding tip, and then solidified. It is preferable to make it.
[0032]
Furthermore, it is preferable to cool a protrusion part in a welding process. This is because it becomes easier to control so that the portions other than the projecting tip of the projecting portion are not melted, and at the same time, adverse effects due to heat on the electrode body, such as thermal deformation of the separator, can be suppressed. As a method of cooling the protruding portion, it can be performed by bringing a heat radiating member having a large heat capacity into contact with the protruding portion. This heat radiating member can also be shared with the above-described jig for thickening the protruding portion. That is, after the projecting portion is pinched by the jig and the projecting tip is gathered to form the thickened portion, the jig can be left as it is until the welding process and can also be used as the heat radiating member.
[0033]
The atmosphere for heating the current collecting electrode is preferably an inert atmosphere for the purpose of preventing deterioration such as oxidation when the current collecting electrode and part of the protruding tip are melted. For example, the current collecting electrode is heated while spraying an inert gas such as argon or helium on the part where the current collecting electrode is in contact with the protruding tip. Here, when heating is performed while spraying an inert gas, the flow of the inert gas is improved due to the presence of the groove portion of the collecting electrode.
[0034]
The method for heating the current collecting electrode is not particularly limited, but it is necessary to melt the current collecting electrode to melt the protruding tip of the electrode body in order to heat the current collecting electrode. For example, arc discharge (welding) and laser heating (welding) can be applied by changing the heating conditions as necessary. Among these, it is preferable to heat the collecting electrode using arc welding, particularly TIG welding, from the viewpoint of good controllability. The polarity of the electrode when performing arc welding is not limited to positive polarity, reverse polarity, and alternating current. However, by using alternating current, the cleaning characteristics of the current collecting electrode are improved and the melt of the collecting electrode vibrates due to application of alternating current. It is preferable from the viewpoint of the effect of removing the oxide film existing at the protruding tip. For example, in the positive electrode of a lithium secondary battery, aluminum must be used for the current collector and collector electrode of the positive electrode plate, and welding between the aluminum must be performed. The oxide film present in the part can be levitated to the melt surface and then removed by a cleaning action.
[0035]
In addition, the oxide film can move sufficiently in the melt even if it does not float up to the surface, and the resistance of the welded part is lower than when the oxide film remains at the interface when heating in a short time. Extremely low. When laser heating is used as a heating method for the current collecting electrode, it is preferable that the heating time can be extended by dispersing the laser light with a lens or the like to control the power and the oxide film can be dispersed in the weld.
[0036]
  As a site | part which heats a current collection electrode, it is the peripheral part of the groove part of a current collection electrode. Furthermore, it is preferable to heat the peripheral part of the groove part of the current collecting electrode that is slightly inside from the edge of the groove part. And as a direction which heats a current collection electrode, the minor axis direction of an electrode bodyOr short width direction(The direction of melting in the direction crossing the direction of the protruding tip of the protruding portion).
[0037]
  As described above, since the current collecting electrode and the projecting portion can be reliably connected from the direction of the projecting tip of the projecting portion, the length of the projecting portion projecting from the edge portion can be suppressed. That is, since the length of the protruding portion that does not participate in the battery reaction can be suppressed, the volume energy efficiency of the final battery is increased.
The battery manufacturing method of the present embodiment has the above-described configuration and at least one of the following components (b-1) to (b-4) as an essential requirement. The components (b-1) to (b-4) described below are the same as those described above as optional components.
(B-1) The welding step is a step of heating the collecting electrode while cooling the protruding portion.
(B-2) The heating method in the welding process is an arc discharge performed from the side opposite to the protruding portion while blowing an inert gas.
(B-3) The portion of the current collecting electrode that contacts the protruding tip of the protruding portion is heated and melted and melted and solidified so as to cover the protruding tip.
(B-4) The welding step is a step performed in an inert atmosphere.
[0038]
【Example】
As an example of the present invention, a battery having a flat wound electrode body was prepared, and the present invention will be described below using an example. Although the drawings may be used to describe the embodiments, even members that are externally different are denoted by the same reference numerals in the drawings when they are substantially the same members in the present invention.
[0039]
(Example)
[Battery configuration]
FIG. 1 shows a part of the battery of the present embodiment, which is a flat wound electrode body 1 and a collecting electrode 2 welded to both ends of the electrode body 1 in the winding axis direction. The electrode body 1 includes a belt-like positive and negative electrode plate (not shown) in which an electrode active material layer (not shown) is formed on the surface of a belt-like current collector (not shown), and a belt-like separator (see FIG. Abbreviation) is wound in a flat shape. Each of the electrode active material layers includes positive and negative electrode active materials. Lithium-manganese composite oxide was used as the positive active material layer, and carbon black was used as the negative active material. The current collector used was a thin film made of aluminum and copper for the positive electrode and the negative electrode, respectively.
[0040]
  Each of the positive and negative electrode plates has a protruding portion 10 on the opposite side to the winding axis of the electrode body 1 and having no electrode active material layer protruding from the opposite electrode plate. The protruding part is a flat wound electrode body.Minor axis directionTo form a thickened portion.
[0041]
  The collecting electrode 2 is a corrugated metal plate having grooves 21 at two locations. As for the material, the collector electrode on the positive electrode side is made of aluminum, and the collector electrode on the negative electrode side is made of copper. When the respective groove portions 21 are combined, the protruding portion 10 of the winding shaft end face of the electrode body 1 to be combined is formed.Minor axis directionAcross the full width. One end of the current collecting electrode 2 is bent at a right angle, and a battery terminal 22 is provided at the bent portion. The current collecting electrode 2 is welded to the projecting tip of the projecting part 10 by heating and melting the peripheral part 212 of the groove part 21.
[0042]
The battery of this example was completed by housing the electrode body 1 with the current collecting electrode 2 welded together with the electrolyte in a battery case (not shown), and then sealing the battery case.
[0043]
[Junction of electrode body (protrusion) and current collecting electrode]
In the battery of the example, the joining of the electrode body 1 and the collecting electrode 2 is performed by melting a part of the collecting electrode 2 in a state where the collecting electrode 2 is disposed on the end face of the electrode body 1 and projecting the melt. 10 and then the melt is cooled and solidified.
[0044]
The process of welding the current collecting electrode 2 to the electrode body 1 will be described. FIG. 2 shows an enlarged part of the electrode body 1 and the collecting electrode 2 that are performing the welding process. The current collecting electrode 2 has a wave shape having two wavy lines, and has a rectangular groove 21 in a part thereof. The protruding portions 10 protruding from the electrode body 1 are grouped into four thickened portions. When the current collecting electrode 2 is brought into contact with the upper part of the electrode body 1, the corrugated wavy portions provided on the current collecting electrode 2 are provided in two protruding portions 10 that are combined into four thickened portions of the electrode body 1. (Contact process).
[0045]
Then, the part located slightly inside from the peripheral part 212 of the groove part 21 of the current collection electrode 2 was heated by arc discharge. Arc discharge was performed by applying alternating current while blowing an inert gas (Ar). This is the same as the method generally referred to as TIG welding except that no filler rod is used. Due to this heating, the peripheral portion 212 of the groove portion 21 of the current collecting electrode 2 is changed from the state in which the protruding tip of the protruding portion 10 is in contact with the peripheral portion 212 of the current collecting electrode 2 as shown in FIG. The state 212 is shifted to a molten state. When the peripheral edge portion 212 is melted, the melt 212m wraps around the protruding portion 10 as shown in FIG. At this time, the protruding portion 10 is always maintained at a temperature below the melting point due to the sufficient heat capacity of the electrode body 1, but a gradually melted portion M is generated from the protruding tip. In the main welding step, the protrusion 10 melts from the tip, so that the shape of the protrusion 10 is maintained.
[0046]
Thereafter, the melt is cooled and solidified to form a welded portion 212 in which the peripheral edge portion 212 and the protruding tip of the protruding portion 10 are integrated, and the current collecting electrode 2 having the positive electrode terminal 22 is connected to the electrode body 1. Electrically joined to the end face (welding process). In addition, also in the current collection electrode 2 which has the negative electrode terminal 22, it electrically joined to the protrusion tip of the protrusion part 10 which laminated | stacked the peripheral part 212 by the method similar to the above.
[0047]
In the present embodiment, the heat radiating member 5 is brought into contact with the protruding portion 10 in order to suppress the thermal influence on the separator included in the electrode body 1. The heat conducted from the current collecting electrode 2 to the protrusion 10 by the heat radiating member 5 is radiated to the heat radiating member 5 and does not adversely affect the inside of the electrode body 1.
[0048]
The battery of the example was formed by enclosing the flat wound electrode body 1 together with an electrolyte in a battery case.
[0049]
In the battery of the example, in order to electrically join the collector electrode on the projecting tip of the projecting portion of the flat wound electrode body, compared to the conventional case in which the collector electrode is joined on the side surface of the projecting portion, Since the projecting length of the projecting portion can be shortened, the flat wound electrode body is miniaturized. Furthermore, the miniaturization of the flat wound electrode body indicates that the battery can be miniaturized.
[0050]
(Modifications 1 and 2)
As shown in FIG. 5, the battery of the modification example has a waveform having four wave lines, whereas the shape of the collecting electrode 2 is a waveform having two wave lines in the embodiment. As shown in FIG. 6, the battery of the modification 2 has a top portion having four wave streaks, whereas the shape of the collecting electrode 2 is a wave having two wave streaks in the embodiment. Each has the same configuration and manufacturing method as the battery of the example, except that has a sharp waveform.
[0051]
(Modification 3)
As shown in FIG. 7, the battery of modification 3 was implemented except that the shape of the collecting electrode 2 was a waveform in the embodiment, whereas the portion in contact with the protruding tip of the electrode body 1 was flat. It is the same configuration and manufacturing method as the battery of the example. The current collecting electrode has two grooves 21. The presence of the groove 21 improves the inert gas permeability in the welding process. Since the battery of the modification 3 has a simple shape of the collecting electrode 2, the molding cost can be reduced. Other than that, the configuration and the manufacturing method are the same as those of the battery of the example.
[0052]
(Modifications 4 to 6)
As shown in FIG. 8, the shape of the current collecting electrode 2 of the battery of the modification 4 is two chevron shapes with a rectangular groove portion in part. The number of peaks provided can be changed (for example, four in the fifth modification shown in FIG. 9).
[0053]
Modification 6 shows an example in which the number of grooves 21 is four (FIG. 10). Other than that, the configuration and the manufacturing method are the same as those of the battery of the example.
[0054]
(Modification 7)
As shown in FIG. 11, the current collecting electrode 2 of the battery according to the modified example 7 is formed into a chevron 23 by pressing only the vicinity of the peripheral edge of the groove to be heated and melted. The projecting tips of the projecting portions 10 are gathered at least at a portion to be welded with a minimum of processing. Other than that, the configuration and the manufacturing method are the same as those of the battery of the example.
[0055]
  (Modifications 8 and 9)
  As shown in FIG. 12, the current collecting electrode 2 of the battery of the modified example 8 has a protruding tip in the welding process.Minor axis directionTwo groove portions 21 are provided in a direction along the direction. The heating and melting of the current collecting electrode 2 in the welding processMajor axis directionThis is performed on the peripheral edge of the groove 21. Other than that, it is the same configuration and manufacturing method as the battery of the example.
[0056]
  Further, as shown in FIG. 13, the collector electrode 2 of the battery of the modified example 9 is further adjacent to the groove portion 24 that melts the collected electrode in the welding process with respect to the collector electrode of the modified example 5.Major axis directionThere is another groove 24 provided along the line. As well as ensuring the permeability of the inert gas, the efficiency of heat conduction can be achieved. Other than that, it is the same configuration and manufacturing method as the battery of the example.
[0057]
(Appendix)
A method for welding the highly productive electrode body and the collecting electrode will be described below.
[0058]
As shown in FIG. 14, a comb-like thickening jig 4 is inserted from the winding shaft end portion of the flat wound electrode body 1 toward the protruding portion 10. The thickening jig 4 is formed by horizontally arranging and integrating five blades having a pointed cross section downward. The tips of the five blades are also pointed. The width below the outermost blade of the thickening jig 4 is slightly larger than the width of the electrode body 1.
[0059]
Since the thickening jig 4 has a sharp point below each blade, the protrusion 10 is divided into four parts. By shifting the thickening jig 4 along the protruding tip of the protruding portion 10 with the protruding portion 10 divided into four, the protruding portion 10 largely forms four thickened portions (FIG. 15). 16). Except for inserting the thickening member 4 from the direction of the protruding tip of the protruding portion, no particularly complicated operation is required, and the thickened portion can be easily formed.
[0060]
  Thereafter, in order to improve heat dissipation, as shown in FIG.Major axis directionTherefore, it is held by the heat radiating member 5. Thereafter, as shown in FIG. 18, the collector electrode 2 is brought into contact with the protruding tip of the protruding portion 10 held by the thickening jig 4.
[0061]
The peripheral edge of the groove 21 of the collector electrode 2 is heated by heating the peripheral edge of the groove 21 of the collector electrode 2 with a TIG welding machine (not shown) while the collector electrode 2 is in contact with the protruding tip. It melts and the current collecting electrode 2 and the protruding tip are welded. At this time, the heat transferred from the collecting electrode 2 to the protruding portion 10 is transferred to the heat radiating member 5 through the thickening jig 4, so that there is no adverse effect on the electrode body 1. A welding process is performed about each of the four peripheral parts 212 of the two groove parts 21 (FIG. 19).
[0062]
【The invention's effect】
The battery of the present invention welds the collecting electrode in contact with the projecting tip of the projecting portion of the electrode body. Therefore, an extra process is not required, and a battery with high productivity and a method for manufacturing the battery are provided. can do.
[Brief description of the drawings]
FIG. 1 is a perspective view showing an electrode body and a collecting electrode of a battery according to an embodiment.
FIG. 2 is a view showing a welding process for welding a collecting electrode to the electrode body of the battery of the example.
FIG. 3 is a cross-sectional view of a contact portion between a protruding portion of a battery electrode body and a collecting electrode after a contact step according to an embodiment and before a welding step.
FIG. 4 is a cross-sectional view when the current collecting electrode and the contact portion between the protruding portion of the battery electrode body and the current collecting electrode are melted during the welding process of the example.
FIG. 5 is a diagram showing a state in which a collecting electrode is brought into contact with a protruding tip of an electrode body of a battery according to Modification 1;
6 is a view showing a state in which a collecting electrode is brought into contact with a protruding tip of an electrode body of a battery according to Modification 2. FIG.
FIG. 7 is a view showing a current collecting electrode of a battery according to Modification 4;
FIG. 8 is a view showing a current collecting electrode of a battery according to Modification 5;
FIG. 9 is a view showing a current collecting electrode of a battery according to Modification 6;
FIG. 10 is a view showing a current collecting electrode of a battery according to Modification 8;
FIG. 11 is a view showing a collecting electrode of a battery according to Modification 9;
12 is a view showing a collecting electrode of a battery according to Modification 10; FIG.
FIG. 13 is a view showing a current collecting electrode of a battery according to Modification 11;
FIG. 14 is a view showing a state in which a protruding portion of an electrode body and a collecting electrode are joined by a thickening jig.
FIG. 15 is a view showing a state in which a protruding portion of an electrode body and a collecting electrode are joined by a thickening jig.
FIG. 16 is a diagram showing a state in which a protruding portion of an electrode body and a collecting electrode are joined by a thickening jig.
FIG. 17 is a diagram showing a state in which a protruding portion of an electrode body and a collecting electrode are joined by a thickening jig.
FIG. 18 is a diagram showing a state in which a protruding portion of an electrode body and a collecting electrode are joined by a thickening jig.
FIG. 19 is a view showing a state in which a protruding portion of an electrode body and a collecting electrode are joined by a thickening jig.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Electrode body 10 ... Protruding part
2 ... Current collecting electrode 21 ... Groove portion 24 ... Other groove portion 212 ... Peripheral portion, welded portion 22 ... Positive electrode terminal, negative electrode terminal
3. TIG welding machine
4. Thickening jig
5 ... Heat dissipation member

Claims (11)

A positive and negative electrode plate and a separator, and at least one of the positive and negative electrode plates has a protruding portion that protrudes from an edge of the other electrode plate, A battery including a flat electrode body formed by winding or laminating a negative electrode plate through the separator,
A flat short width direction which is at least a part of the end face of the electrode body and is the same as the flat short diameter direction formed by winding or the flat shape formed by stacking the flat shapes. A collecting electrode having a size covering the protruding tips of the plurality of protruding portions arranged along the line,
The current collecting electrode has a groove portion arranged along the minor axis direction or the minor width direction of the electrode body,
The current collecting electrode is joined to the protruding portion of the electrode body through the peripheral edge of the groove ,
The current collecting electrode has a corrugated shape in which an end surface of the electrode body on a side where the protruding portion of the electrode body protrudes has a wavy line extending in a direction perpendicular to the short diameter direction or the short width direction. The current collecting electrode is joined to the protruding portion of the electrode at the corrugated portion . A positive and negative electrode plate and a separator, and at least one of the positive and negative electrode plates has a protruding portion that protrudes from an edge of the other electrode plate, A battery including a flat electrode body formed by winding or laminating a negative electrode plate through the separator,
A flat short width direction which is at least a part of the end face of the electrode body and is the same as the flat short diameter direction formed by winding or the flat shape formed by stacking the flat shapes. A collecting electrode having a size covering the protruding tips of the plurality of protruding portions arranged along the line,
The current collecting electrode has a groove portion arranged along the short diameter direction or the short width direction of the electrode body and another groove portion arranged in a direction intersecting the groove portion ,
The current collecting electrode is joined to the projecting portion of the electrode body via the peripheral edge of the groove ,
The battery, wherein the current collecting electrode is joined to the protruding portion of the electrode body within a range surrounded by the other groove portion and the groove portion . A positive and negative electrode plate and a separator, and at least one of the positive and negative electrode plates has a protruding portion that protrudes from an edge of the other electrode plate, A battery including a flat electrode body formed by winding or laminating a negative electrode plate through the separator,
A flat short width direction which is at least a part of the end face of the electrode body and is the same as the flat short diameter direction formed by winding or the flat shape formed by stacking the flat shapes. A collecting electrode having a size covering the protruding tips of the plurality of protruding portions arranged along the line,
The current collecting electrode has a groove portion arranged along the minor axis direction or the minor width direction of the electrode body,
The current collecting electrode is joined to the protruding portion of the electrode body through the peripheral edge of the groove ,
The battery is characterized in that the current collecting electrode has a shape that covers the entire protruding tip of the protruding portion . The battery according to any one of claims 1 to 3, wherein the collector electrode has a plate shape. The groove there are a plurality of battery according to any one of claims 1-4, which is bonded to all of the projecting portion in the minor diameter direction or the short width direction of the end face of the electrode body as a whole. The electrode body includes a plurality of thickening portions formed by overlapping a plurality of the protruding portions in the short diameter direction or the short width direction, and the current collecting electrode is provided in the plurality of thickening portions. the battery according to any one of claims 1 to 5, which is joined. The battery according to claim 6 , wherein the plurality of thickening portions are joined together to form the corrugated portion of the current collecting electrode. A positive and negative electrode plate and a separator, and at least one of the positive and negative electrode plates has a protruding portion that protrudes from an edge of the other electrode plate, A method for producing a battery comprising a flat electrode body formed by winding or laminating a negative electrode plate through the separator,
A flat short width direction which is at least a part of the end face of the electrode body and is the same as the flat short diameter direction formed by winding or the flat shape formed by stacking the flat shapes. A current collecting electrode having a size covering the projecting tips of the plurality of projecting portions arranged along the line and having a groove portion disposed along the minor axis direction or the minor width direction of the electrode body, A contact step of contacting the protruding tip of the protruding portion of the electrode body;
A welding step of heating the current collecting electrode and welding the current collecting electrode to the projecting tip until the peripheral edge of the groove portion in contact with the projecting portion of the current collecting electrode is melted;
I have a,
The method of manufacturing a battery, wherein the welding step is a step of heating the current collecting electrode while cooling the protrusion . A positive and negative electrode plate and a separator, and at least one of the positive and negative electrode plates has a protruding portion that protrudes from an edge of the other electrode plate, A method for producing a battery comprising a flat electrode body formed by winding or laminating a negative electrode plate through the separator,
A flat short width direction which is at least a part of the end face of the electrode body and is the same as the flat short diameter direction formed by winding or the flat shape formed by stacking the flat shapes. A current collecting electrode having a size covering the projecting tips of the plurality of projecting portions arranged along the line and having a groove portion disposed along the minor axis direction or the minor width direction of the electrode body, A contact step of contacting the protruding tip of the protruding portion of the electrode body;
A welding step of heating the current collecting electrode and welding the current collecting electrode to the projecting tip until the peripheral edge of the groove portion in contact with the projecting portion of the current collecting electrode is melted;
I have a,
The battery manufacturing method according to claim 1, wherein the heating method in the welding step is arc discharge performed from the opposite side to the protruding portion while blowing an inert gas . A positive and negative electrode plate and a separator, and at least one of the positive and negative electrode plates has a protruding portion that protrudes from an edge of the other electrode plate, A method for producing a battery comprising a flat electrode body formed by winding or laminating a negative electrode plate through the separator,
A flat short width direction which is at least a part of the end face of the electrode body and is the same as the flat short diameter direction formed by winding or the flat shape formed by stacking the flat shapes. A current collecting electrode having a size covering the projecting tips of the plurality of projecting portions arranged along the line and having a groove portion disposed along the minor axis direction or the minor width direction of the electrode body, A contact step of contacting the protruding tip of the protruding portion of the electrode body;
A welding step of heating the current collecting electrode and welding the current collecting electrode to the projecting tip until the peripheral edge of the groove portion in contact with the projecting portion of the current collecting electrode is melted;
I have a,
A method for manufacturing a battery, comprising: heating and melting a portion of the current collecting electrode that is in contact with a protruding tip of the protruding portion so as to cover the protruding tip . A positive and negative electrode plate and a separator, and at least one of the positive and negative electrode plates has a protruding portion that protrudes from an edge of the other electrode plate, A method for producing a battery comprising a flat electrode body formed by winding or laminating a negative electrode plate through the separator,
A flat short width direction which is at least a part of the end face of the electrode body and is the same as the flat short diameter direction formed by winding or the flat shape formed by stacking the flat shapes. A current collecting electrode having a size covering the projecting tips of the plurality of projecting portions arranged along the line and having a groove portion disposed along the minor axis direction or the minor width direction of the electrode body, A contact step of contacting the protruding tip of the protruding portion of the electrode body;
A welding step of heating the current collecting electrode and welding the current collecting electrode to the projecting tip until the peripheral edge of the groove portion in contact with the projecting portion of the current collecting electrode is melted;
I have a,
The method for manufacturing a battery, wherein the welding step is a step performed in an inert atmosphere .

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