JP2012169085A - Battery and method for manufacturing battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a battery with a small number of components, and to provide a method for manufacturing the battery.SOLUTION: The method for manufacturing the battery comprises: arranging a bolt 170 in a die 1000 and forming a coating film F1 on a head 171 of the bolt 170 by injection molding; then arranging the bolt 170 having the coating film F1 formed thereon, a lid body 130 and a positive electrode terminal 50 in a die 2000 and integrating them by injection molding; then immersing the integrated product in a removing agent for a coating film to remove the coating film F1 and forming a structure 200; joining a wound electrode 10 to the structure 200; and joining the joined product to a battery container body 120 so that the wound electrode 10 is arranged inside the battery container body 120.

Description

  The present invention relates to a battery and a battery manufacturing method. More specifically, the present invention relates to a battery having a small number of parts and a battery manufacturing method.

  Batteries are used in various fields such as electronic devices such as mobile phones and personal computers, vehicles such as hybrid vehicles and electric vehicles. Of these, assembled batteries in which single cells are connected in series or in parallel are generally mounted on vehicles and large electronic devices.

  Some battery packs have battery cell electrode terminals connected to each other via a bus bar in order to electrically connect the battery cells. A connection method using a bolt and a nut may be used for the connection between the bus bar and the electrode terminal. In this case, if the fastening with the bolt and the nut is not suitably performed, the fastening may be loosened with time. A battery with a loose fastening point has a large electrical resistance. Therefore, it is preferable to perform fastening securely.

  FIG. 1 of Patent Document 1 shows a battery pack in which electrode terminals are connected to each other by a bus bar. In this case, as shown in FIG. 4 of the patent document, the external electrode terminal and the internal electrode terminal are electrically connected by a caulking structure. The bolt is disposed so as to be sandwiched between the insulating member and the external electrode terminal. Therefore, the bolt is prevented from coming off from the lid and the external electrode terminal. However, the bolt is not fixed to the lid and the external electrode terminal. There is slight play (see FIG. 4 of Patent Document 1).

  Without this play, when the electrode terminals are fastened by the bus bar, the bolts and nuts may not be fastened properly. If the fastening is not suitably performed, the contact resistance between the bus bar and the electrode terminal may be large. In this case, the performance of the battery pack is low. Even if the fastening itself is suitably performed, stress may be applied to the external electrode terminal. The stress may be applied to the electrode body through the internal electrode terminal. This stress may distort the electrode body.

JP 2008-192595 A

  Incidentally, in the battery pack described in Patent Document 1, it is necessary to provide external electrode terminals (41 in FIGS. 3 and 4 of Patent Document 1) and internal electrode terminals (71 and 51 in FIG. 3 of Patent Document 1). In this case, the number of parts is large. Therefore, the cost is high. There are also many assembly processes. In other words, the cycle time is long. Therefore, it is preferable to manufacture a battery with a small number of parts.

  The present invention has been made to solve the above-described problems of the prior art. That is, the problem is to provide a battery with a small number of parts and a battery manufacturing method.

  A battery according to an embodiment of the present invention, which has been made for the purpose of solving this problem, includes an electrode body that is a power generation element, an electrode terminal that is electrically connected to the electrode body and provided with a through hole, and an electrode body. A battery container body for containing the electrolyte and electrolyte, a lid joined to the battery container body, an insulating member that insulates the electrode terminal from the lid and is provided with a recess, and is disposed in the recess And a bolt having a screw shaft penetrating the through hole. Further, the lid and the electrode terminal are integrally formed via an insulating member. A film is formed on at least a part of the surface of the head of the bolt and the surface of the recess of the insulating member. The number of parts of such a battery is small. In addition, when the electrode terminals are fastened to each other using a bus bar to form an assembled battery, the battery can be suitably fastened.

  In the battery described above, the material of the coating is preferably a resin that dissolves in a predetermined solvent, and the material of the insulating member may be a material that does not dissolve in the predetermined solvent. This is because a gap is formed between the bolt and the insulating member.

  In the battery described above, the material of the resin that dissolves in the predetermined solvent may be any one of polycarbonate, polyvinyl chloride, and polypropylene. This is because the resin is sufficiently dissolved. Therefore, the film is not so thick.

  In another aspect of the present invention, a battery manufacturing method includes an electrode body creation step of creating an electrode body that is a power generation element, and a structure in which a lid body, an electrode terminal, and a bolt are integrated via an insulating member. This is a method including a structure creating step to be created, and a unit cell creating step in which an electrode body is arranged inside the battery container and an electrolytic solution is injected and sealed with the structure. The structure creating step includes a film forming step of forming a film with a first resin on the head of the bolt, and an insulating member forming step of forming an insulating member by integrating the bolt film, the lid, and the electrode terminal. And a film removal step for removing the film. In such a battery manufacturing method, the number of manufacturing steps is small. This is because the number of parts is small. For example, there is no need to provide a caulking structure.

  In the battery manufacturing method described above, in the film removal step, a solvent that dissolves the film and does not dissolve the insulating member may be used. This is because only the coating covering the bolt can be removed.

  In the battery manufacturing method described above, it is more preferable that the solvent used in the film removal step is a cleaning solution for cleaning the structure. This is because there is no need to separately provide a process for cleaning the structure itself. That is, the cycle time is short.

  In the battery manufacturing method described above, the combination of the first resin and the solvent is a combination of polycarbonate and acetone, polyvinyl chloride and acetone, polypropylene and acetone, polyvinyl chloride and ethanol, respectively. It is good that either. This is because the structure can be formed more suitably.

  In the battery manufacturing method described above, it is preferable to have an assembled battery production step of forming an assembled battery by fastening the electrode terminal of the single battery and the bus bar. This is because the assembled battery can be produced by suitably fastening the electrode terminal and the bus bar.

  According to the present invention, a battery having a small number of parts and a method for manufacturing the battery are provided.

It is a perspective view for demonstrating the battery pack which concerns on embodiment. It is a perspective view for demonstrating schematic structure of the battery which concerns on embodiment. It is a perspective view for demonstrating the winding electrode body of the battery which concerns on embodiment. It is an expanded view for demonstrating the winding structure of the winding electrode body of the battery which concerns on embodiment. It is sectional drawing for demonstrating the cross-section of the electrode plate of the winding electrode body of the battery which concerns on embodiment. It is a perspective view for demonstrating the structure of the cover body and electrode terminal of the battery which concerns on embodiment. It is sectional drawing for demonstrating the cross-section of the structure of the battery cover body and electrode terminal which concerns on embodiment. It is a figure which shows the volt | bolt which comprises the battery which concerns on embodiment. It is sectional drawing (the 1) for demonstrating the manufacturing method of the battery which concerns on embodiment. It is sectional drawing (the 2) for demonstrating the manufacturing method of the battery which concerns on embodiment. It is sectional drawing (the 3) for demonstrating the manufacturing method of the battery which concerns on embodiment. It is sectional drawing for demonstrating the manufacturing method of the battery which concerns on embodiment (the 4). It is sectional drawing for demonstrating the manufacturing method of the battery which concerns on embodiment (the 5). It is sectional drawing for demonstrating the manufacturing method of the battery which concerns on embodiment (the 6). It is sectional drawing to which the bolt vicinity of the battery which concerns on embodiment was expanded. It is a perspective view for demonstrating the structure of the cover body and electrode terminal of another battery which concerns on embodiment.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments embodying the present invention will be described below in detail with reference to the accompanying drawings. In the present embodiment, the present invention is embodied with respect to a lithium ion secondary battery and a manufacturing method thereof.

1. Basic Structure of Battery Pack The battery pack BP of this embodiment is an assembled battery in which batteries 100 are connected in series as shown in FIG. The battery 100 is a rectangular unit cell. In the battery pack BP, as shown in FIG. 1, the positive terminal 50 of the battery 100 and the negative terminal 60 of the battery 100 adjacent to the battery 100 are fastened via a bus bar 190. This fastening is made with bolts and nuts.

  A schematic configuration of the battery 100 is shown in a perspective projection view of FIG. FIG. 2 shows the battery 100 taken out from the battery pack BP shown in FIG. The battery 100 has a flat wound electrode body 10 shown in FIG. As shown in FIG. 2, the battery container 110 includes a battery container main body 120 and a lid 130. A wound electrode body 10 is disposed inside the battery container 110. The wound electrode body 10 is a power generation element that actually contributes to power generation. The lid 130 is joined to the battery container main body 120.

An electrolyte is injected into the battery container 110. The electrolytic solution injected into the battery container 110 is obtained by dissolving an electrolyte in an organic solvent. Examples of organic solvents include ester solvents such as propylene carbonate (PC), ethylene carbonate (EC), dimethyl carbonate (DMC), and ethyl methyl carbonate (EMC), and ester solvents such as γ-butyrolactone (γ-BL), di- An organic solvent containing an ether solvent such as ethoxyethane (DEE) can be used. As the electrolyte salt, lithium salts such as lithium perchlorate (LiClO ₄ ), lithium borofluoride (LiBF ₄ ), and lithium hexafluorophosphate (LiPF ₆ ) can be used.

  As shown in FIG. 2, the battery 100 includes a positive terminal 50, a negative terminal 60, an insulating member 150, an insulating member 160, and bolts 170 and 180. Details of these will be described later.

  FIG. 3 is a perspective view showing the wound electrode body 10. As shown in FIG. 3, the wound electrode body 10 has a flat shape. A positive electrode end portion 30 projects from one end portion of the wound electrode body 10. As will be described later, the positive electrode end 30 is a portion where the positive electrode core material of the positive electrode plate protrudes. A negative electrode end 40 protrudes from the other end of the wound electrode body 10. The negative electrode end 40 is a portion where the negative electrode core material of the negative electrode plate protrudes, as will be described later.

  FIG. 4 is a development view showing a wound structure of the wound electrode body 10. As shown in FIG. 4, the wound electrode body 10 is wound in a state where the positive electrode plate P, the separator S, the negative electrode plate N, and the separator T are stacked in this order from the inside. That is, the wound electrode body 10 is configured such that the positive plates P and the negative plates N are alternately arranged with the separators S and T interposed therebetween.

The positive electrode plate P is obtained by applying a composite material containing a positive electrode active material capable of inserting and extracting lithium ions to an aluminum foil as a positive electrode core material. As the positive electrode active material, lithium composite oxides such as lithium nickelate (LiNiO ₂ ), lithium manganate (LiMnO ₂ ), and lithium cobaltate (LiCoO ₂ ) are used. The negative electrode plate N is obtained by applying a composite material containing a negative electrode active material capable of occluding and releasing lithium ions to a copper foil as a negative electrode core material. As the negative electrode active material, carbon-based materials such as amorphous carbon, non-graphitizable carbon, graphitizable carbon, and graphite are used.

  As shown in FIG. 4, the positive electrode plate P has a positive electrode coating part P1 and a positive electrode non-coating part P2. The positive electrode coating part P1 is a place where a positive electrode mixture layer containing a positive electrode active material or the like is formed on a positive electrode core material. The positive electrode non-coated portion P2 is a portion where the positive electrode mixture layer is not formed on the positive electrode core material. The negative electrode plate N includes a negative electrode coating portion N1 and a negative electrode non-coating portion N2. The negative electrode coating portion N1 is a portion where a negative electrode mixture layer containing a negative electrode active material or the like is formed on a negative electrode core material. The negative electrode non-coated portion N2 is a portion where the negative electrode mixture layer is not formed on the negative electrode core material.

  An arrow A in FIG. 4 indicates the width direction (lateral direction in FIG. 3) of the positive electrode plate P, the negative electrode plate N, and the separators S and T. An arrow B in FIG. 4 indicates the longitudinal direction of the positive electrode plate P, the negative electrode plate N, the separators S and T (the circumferential direction of the wound electrode body 10 in FIG. 3).

  The separators S and T are porous films such as polyethylene and polypropylene. The thicknesses of the separators S and T are about 10 to 50 μm. Here, the separator S and the separator T are made of the same material. For the understanding of the above winding order, only the codes are distinguished as S and T.

  FIG. 5 is a perspective sectional view of the positive electrode plate P (or the negative electrode plate N). In FIG. 5, each symbol outside the parentheses indicates each part in the case of the positive electrode, and each symbol in the parenthesis indicates each part in the case of the negative electrode. The direction indicated by the arrow A in FIG. 5 is the same as the direction indicated by the arrow A in FIG. That is, it is the width direction of the positive electrode plate P (or the negative electrode plate N). The direction indicated by arrow B in FIG. 5 is the same as the direction indicated by arrow B in FIG. That is, it is the longitudinal direction of the positive electrode plate P (or the negative electrode plate N).

  As shown in FIG. 5, the positive electrode plate P is obtained by forming a positive electrode mixture layer PA on a part of both surfaces of a strip-like positive electrode core material PB. On the left side in FIG. 5, the positive electrode non-coated portion P2 of the positive electrode plate P protrudes in the width direction. The positive electrode non-coated portion P2 is formed in a strip shape. The positive electrode non-coated portion P2 is a region where the positive electrode active material is not applied to both surfaces of the positive electrode core material PB. Therefore, in the positive electrode non-coating portion P2, the positive electrode core material PB is still exposed. On the other hand, there is no protrusion corresponding to the positive electrode non-coated portion P2 on the right side in FIG. In the positive electrode coating part P1, the positive electrode mixture layer PA is formed with a uniform thickness on both surfaces of the positive electrode core material PB.

  As indicated by the reference numerals in parentheses in FIG. 5, the negative electrode plate N is obtained by forming a negative electrode mixture layer NA on a part of both surfaces of a strip-shaped negative electrode core material NB. On the left side in FIG. 5, a negative electrode non-coated portion N2 of the negative electrode plate N protrudes in the width direction. The negative electrode non-coated portion N2 is formed in a strip shape. The negative electrode non-coated portion N2 is a region where the negative electrode active material is not applied to both surfaces of the negative electrode core material NB. Therefore, in the negative electrode non-coating portion N2, the negative electrode core material NB is still exposed. On the other hand, there is no protrusion corresponding to the negative electrode non-coated portion N2 on the right side in FIG. In the negative electrode coating portion N1, the negative electrode mixture layer NA is formed with a uniform thickness on both surfaces of the negative electrode core material NB. However, as shown in FIG. 4, at the time of winding, the positive electrode non-coated portion P2 and the negative electrode non-coated portion N2 are wound in a state of protruding to the opposite side.

2. Integrated Structure of Lid and Electrode Terminal In battery 100 according to this embodiment, lid 130 and electrode terminals 50 and 60 have an integral structure. This integrated structure is shown in FIG. As shown in FIG. 6, the structure 200 includes a lid 130, a positive terminal 50, a negative terminal 60, insulating members 150 and 160, and bolts 170 and 180. As will be described later, the lid body 130, the positive electrode terminal 50, and the negative electrode terminal 60 are integrally formed via insulating members 150 and 160.

  The positive terminal 50 is a positive terminal that is electrically connected to the positive end 30 of the wound electrode body 10. The positive electrode terminal 50 is welded to the positive electrode end 30 of the wound electrode body 10. Thereby, the positive electrode terminal 50 can collect current from the wound electrode body 10. Of course, the electrical connection method between the positive electrode terminal 50 and the positive electrode end 30 may be a method other than welding.

  The negative electrode terminal 60 is a negative electrode side terminal electrically connected to the negative electrode end 40 of the wound electrode body 10. The negative electrode terminal 60 is welded to the negative electrode end portion 40 of the wound electrode body 10. As a result, the negative electrode terminal 60 can collect current from the wound electrode body 10. Of course, a method other than welding may be used as an electrical connection method between the negative electrode terminal 60 and the negative electrode end 40.

  The insulating member 150 is a member for insulating the lid body 130 from the positive electrode terminal 50. Therefore, the insulating member 150 is formed so that the lid 130 and the positive electrode terminal 50 do not come into contact with each other. The material of the insulating member 150 is resin as will be described later. The insulating member 150 is also for sealing the battery 100.

  The insulating member 160 is a member for insulating the lid body 130 and the negative electrode terminal 60. Therefore, the insulating member 160 is formed so that the lid 130 and the negative electrode terminal 60 do not come into contact with each other. The material of the insulating member 160 is resin as will be described later. The same resin as the insulating member 150 may be used as this resin. The insulating member 160 is also for sealing the battery 100.

  The bolt 170 is for fastening the positive electrode terminal 50 and the bus bar 190 together with the nut. The bolt 180 is for fastening the negative electrode terminal 60 and the bus bar 190 together with the nut.

  FIG. 7 is a cross-sectional view schematically showing the positive electrode side of the structure 200. As shown in FIG. 7, the lid body 130 and the positive electrode terminal 50 are integrally formed via an insulating member 150. As described above, the insulating member 150 is arranged between the lid 130 and the positive terminal 50. Therefore, these members are insulated from each other.

  As shown in FIG. 7, the head 171 of the bolt 170 is disposed inside the recess 151 of the insulating member 150. However, the shape of the recess 151 is slightly larger than the head 171. Therefore, the head 171 of the bolt 170 is not fixed to the recess 151 of the insulating member 150. As shown in FIG. 7, the screw shaft 172 of the bolt 170 is inside the through hole 54 of the fastened portion 51 of the positive electrode terminal 50. That is, the screw shaft 172 passes through the through hole 54. However, the diameter of the through hole 54 is larger than the diameter of the screw shaft 172. Therefore, the screw shaft 172 of the bolt 170 is not fixed to the through hole 54 of the positive electrode terminal 50.

  The head 171 of the bolt 170 is located between the recess 151 of the insulating member 150 and the positive terminal 50. That is, the head 171 of the bolt 170 is sandwiched between the recess 151 of the insulating member 150 and the fastened portion 51 of the positive terminal 50. The shaft 172 of the bolt 170 passes through the through hole 54 of the positive electrode terminal 50. The diameter of the through hole 54 is smaller than the diameter of the head 171 of the bolt 170. Therefore, the bolt 170 does not fall out of the through hole 54.

  In this way, the bolt 170 is prevented from being detached from the structure 200. However, the insulating member 150 and the positive electrode terminal 50 are not fixed. The same applies to the bolt 180 on the negative electrode side.

  As described above, in the structure 200 of this embodiment, there is a slight gap SP between the bolts 170 and 180 and the insulating members 150 and 160. Therefore, when the battery 100 is an assembled battery, the positive terminal 50 or the negative terminal 60 and the bus bar 190 can be suitably fastened. Therefore, after fastening, the contact resistance between the positive electrode terminal 50 or the negative electrode terminal 60 and the bus bar is low.

  In the structure 200, the lid 130 and the insulating members 150 and 160 are integrally formed. Therefore, the airtightness of the battery 100 is higher than the airtightness of a battery having a caulking structure (see FIG. 4 of Patent Document 1). Therefore, there is almost no risk of electrolyte leakage. Further, the number of parts of the battery 100 is smaller than the number of parts of the battery having a caulking structure. Therefore, the cost is low.

3. Method of integrally forming the lid and electrode terminal (structuring process)
3-1. Film Forming Step Here, a method for forming the structure 200 will be described. First, the bolt 170 shown in FIG. 8 is arranged inside the mold 1000 as shown in FIG. Here, the bolt 170 and the bolt 180 shown in FIG. 2 and the like differ only in whether the battery 100 is disposed on the positive electrode side or the negative electrode side. In other words, the rest is the same. Therefore, it is not necessary to distinguish between the bolt 170 and the bolt 180 in this process. Therefore, the positive electrode side will be described.

  As shown in FIG. 9, the mold 1000 after the bolt 170 is disposed has a cavity C1. The cavity C1 is in a position that covers the head 171 of the bolt 170. However, the cavity C1 is not in a position facing the seating surface 173 of the bolt 170. Therefore, no coating is formed on the seating surface 173 of the bolt 170 in this process.

  Subsequently, a film is formed at the location of the cavity C1 by injection molding. Therefore, as shown in FIG. 10, the first resin is poured into the cavity C1 of the mold 1000 from the gate (not shown). This first resin is, for example, polycarbonate (PC). As will be described later, the first resin is soluble in a predetermined solvent. After the resin has spread to the cavity C1, the resin is cooled. After cooling, a film is formed on the head 171 of the bolt 170.

  FIG. 11 shows the bolt 170 after being removed from the mold 1000. A coating F <b> 1 is formed on the head 171 of the bolt 170. That is, the coating F1 covers the head 171 of the bolt 170. However, the coating F1 does not cover the seating surface 173. Note that the material of the coating F1 is the first resin. The thickness of the coating F1 is not less than 0.01 mm and not more than 1 mm.

3-2. Insulating member forming step Subsequently, insulating members 150 and 160 are formed on the lid 130. Since this process is the same on the positive electrode side and the negative electrode side, the positive electrode side will be described. As shown in FIG. 12, a lid body 130, a positive electrode terminal 50, and a bolt 170 on which a film F1 is formed are arranged in a mold 2000. Next, as shown in FIG. 13, the second resin is poured into the cavity C <b> 2 (see FIG. 12) of the mold 2000 to mold the insulating member 150.

  At this time, the coating F1 formed on the bolt 170 is in contact with the second resin. However, the bolt 170 does not contact the second resin. That is, the second resin is bonded to the coating F1 of the bolt 170, but is not bonded to the main body of the bolt 170.

  In the insulating member forming step, the lid 130 and the positive terminal 50 are combined with the second resin. At that time, it is advisable to use an adhesive functional surface treatment. This is because the lid 130 and the positive electrode terminal 50 are more strongly bonded to the second resin. The second resin becomes the insulating member 150 after cooling. Thereby, as shown in FIG. 14, the coating F <b> 1 of the bolt 170, the lid body 130, and the positive electrode terminal 50 are integrally formed via the insulating member 150. At this time, the structure shown in FIG. 14 is different from the structure 200 shown in FIG. 7 in that the film F1 is formed.

  The insulating member 160 can be similarly formed on the negative electrode side. Thereby, as shown in FIG. 6, the structure 200 in which the insulating member 160, the negative electrode terminal 60, the lid body 130, and the bolt 180 are integrally formed is obtained. The forming of the insulating member 150 on the positive electrode side and the forming of the insulating member 160 on the negative electrode side may be performed in separate steps or may be performed in the same step. Of course, the cycle time is shorter when the processes are performed together.

3-3. Film Removal Step Next, the film F1 formed on the heads 171 and 181 of the bolts 170 and 180 is removed. For this purpose, a film remover is used. This film removing agent is a solvent for dissolving the film F1. For example, acetone. Since this film removing agent needs to dissolve the film F1, it is selected in combination with the first resin as described later. The second resin, which is the material of the insulating members 150 and 160, is selected so that it does not dissolve in the film removing agent.

  Specifically, the structure 200 is immersed in a film removing agent. Thereby, a part of the film F1 is exposed to the film removing agent. The coating film F1 is dissolved in the coating film removing agent from the portion in contact with the coating film removing agent in the coating film F1. Thus, the film F1 is removed by immersing the structure 200 in the film removing agent. However, as will be described later, a part of the coating F1 may remain between the recess 151 of the insulating resin 150 and the head 171 of the bolt 170. This is because it is difficult to completely remove the film F1.

  Thereby, the structure 200 shown in FIG. 7 is obtained. As described above, the bolts 170 and 180 of the structure 200 are not fixed to the insulating members 150 and 160, respectively.

3-4. Combination of Film Forming Resin and Film Removing Agent Here, the combination of the film forming resin (first resin) that becomes the film F1 and the film removing agent will be described. As described above, it is necessary to select a suitable combination of the film forming resin and the film removing agent for dissolving the film forming resin. This is because whether or not the coating F1 can be sufficiently removed is changed by this selection. Further, the time required for removing the coating F1 is different. In other words, it affects the cycle time.

  Table 1 shows a combination of a film forming resin and a film removing agent that dissolves the film forming resin.

[Table 1]
Resin Film remover Polycarbonate (PC) Acetone polyvinyl chloride (PVC) Acetone polypropylene (PP) Acetone polyvinyl chloride (PVC) Ethanol

4). Battery Manufacturing Method Next, a method for manufacturing the battery pack BP will be described. The battery manufacturing method of this embodiment is characterized in that the battery is manufactured using the structure 200 manufactured by the method of integrally forming the lid 130 and the electrode terminals 50 and 60 described above.

4-1. Electrode plate preparation process First, the positive electrode coating liquid is applied to the aluminum foil which is the positive electrode core material PB, and the positive electrode paste layer is formed. This positive electrode coating solution is obtained by kneading the above positive electrode active material or the like in a solvent. Next, the positive electrode paste layer on which the positive electrode paste layer is formed is dried while being conveyed into the drying furnace. Thereby, the positive electrode mixture layer PA is formed on the positive electrode core material PB. The positive electrode mixture layer PA is a layer containing a positive electrode active material. The positive electrode mixture layer PA is bound to the positive electrode core material PB. The positive electrode mixture layer PA is preferably formed on both surfaces of the positive electrode core material PB. Thereby, the positive electrode plate P is created. The same applies to the negative electrode plate N.

4-2. Next, the positive electrode plate P and the negative electrode plate N are wound with the separators S and T interposed therebetween. These winding orders are the order of the positive electrode plate P, the separator S, the negative electrode plate N, and the separator T from the inside as shown in FIG. Thereby, a cylindrical wound electrode body is created. Then, by pressing the cylindrical wound electrode body from the side of the cylindrical side surface, the flat wound electrode body 10 shown in FIG. 3 is created.

4-3. Structure Creation Step Subsequently, as described above, the structure 200 is created by the structure creation step. The structure creating process includes a film forming process, an insulating member forming process, and a film removing process. The positive terminal 50 and the negative terminal 60 are joined to the lid 130 via the insulating member 150 and the insulating member 160, respectively. Thereby, the structure 200 shown in FIG. 6 etc. is created. In addition, the order of the said process, an electrode plate creation process, and an electrode body creation process may be replaced.

4-4. Single Cell Making Step Subsequently, the positive electrode end portion 30 of the wound electrode body 10 is welded to the positive electrode terminal 50. Further, the negative electrode end 40 of the wound electrode body 10 is welded to the negative electrode terminal 60. Then, the welded body is disposed on the battery container main body 120. At this time, the wound electrode body 10 is disposed inside the battery container body 120. Then, the battery container main body 120 is sealed with the lid 130 of the welded body. And electrolyte solution is inject | poured into the inside of the battery container 110 from a liquid injection port.

  Thereby, the battery 100 is assembled. After this, it is advisable to perform processing such as conditioning and aging and various inspection processes. The battery 100 is created through the above steps.

4-5. Next, a plurality of batteries 100 are electrically connected to create a battery pack BP. First, as shown in FIG. 1, the load members 191 and 192 are loaded with the plurality of batteries 100 sandwiched therebetween. Then, as shown in FIG. 1, the positive terminal 50 of one battery 100 and the negative terminal 60 of the adjacent battery 100 are connected via a bus bar 190. By performing this fastening, the battery pack BP is manufactured as shown in FIG.

4-6. Manufactured Battery FIG. 15 shows an enlarged view around the bolt 170 of the battery 100 manufactured as described above. As shown in FIG. 15, a thin coating 210 is formed on the head 171 of the bolt 170. The region covered with the coating 210 is at least a part of the surface of the head 171 of the bolt 170. This film 210 is a residual film of the film F1 that could not be completely removed even by cleaning with a cleaning agent. These residual coatings do not adversely affect the battery performance of the battery 100.

  Further, as shown in FIG. 15, a thin coating 220 is formed on the surface of the recess 151 in the insulating member 150. The region covered with the coating 220 is at least a part of the surface of the recess 151 in the insulating member 150. This film 220 is also a residual film of the film F1 that could not be completely removed even by cleaning with a cleaning agent.

  As described above, even after the battery 100 is completed, at least a part of the coating F1 covering the head 171 of the bolt 170 remains. These coatings 210 and 220 do not cover the entire gap between the recess 151 of the insulating member 150 and the head 171 of the bolt 170. The material of the coatings 210 and 220 is the same as that of the first resin. As described above, since the coatings 210 and 220 remain in the battery 100, it is possible to examine the components.

  In FIG. 15, the coatings 210 and 220 are formed on both the surface of the head 171 of the bolt 170 and the surface of the recess 151 of the insulating member 150. However, it may remain in at least one of these. Although the description has been given here on the positive electrode side, the same applies to the negative electrode side.

5. Modified example 5-1. Cleaning step In the present embodiment, a coating removal step for dissolving and removing the coating is provided. However, the film removing agent may also serve as a cleaning liquid for the structure 200. This is because the surface of the structure 200 can be cleaned. That is, the coating removal process and the cleaning process can be integrated. Thereby, the cycle time can be further shortened.

5-2. Shape of Electrode Terminal and Insulating Member The shape of the electrode terminal and insulating member is not limited to that shown in FIG. For example, the shape shown in FIG. The insulating members 350 and 360 in FIG. 16 are thinner than the insulating members 150 and 160 in FIG. In addition, the shapes of the positive electrode terminal 370 and the negative electrode terminal 380 are slightly different from the shapes of the positive electrode terminal 50 and the negative electrode terminal 60.

5-3. Insulating member material In this embodiment, the insulating members 150 and 160 are formed by injection molding. However, the insulating members 150 and 160 may be formed by other methods. However, the insulating members 150 and 160 are made of an insulating material. If so, it is not limited to resin.

5-4. Shape of Electrode Body In this embodiment, a method for manufacturing a lithium ion secondary battery including the flat wound electrode body 10 has been described. However, it is not limited to a battery having a flat electrode body. The present invention can also be applied to a cylindrical battery having a cylindrical electrode body. Further, the present invention can also be applied to a battery using an electrode body in which a positive electrode plate and a negative electrode plate are stacked without winding. In the case of using flatly stacked electrode bodies, a step of winding the electrode plate or the like, or a pressing step of flattening the wound cylindrical electrode body is not essential.

5-4. Battery type Not limited to lithium ion secondary batteries. The present invention can also be applied to nickel metal hydride batteries and other secondary batteries. In this case, the configuration of the electrode body is different from that of the lithium ion secondary battery. Therefore, the electrode plate creation process may not be necessary. However, even these batteries require an electrode body that is a power generation element.

6). Summary As described above in detail, in the battery manufacturing method of this embodiment, the electrode terminals 50 and 60 are formed integrally with the lid 130 via the insulating members 150 and 160. At that time, a film F <b> 1 is formed on the head 171 of the bolt 170. Then, the insulating member 150 is formed on the coating F1. Thereafter, the coating F1 is removed. Thereby, the manufacturing method of a battery with few manufacturing processes is implement | achieved.

  In the battery 100 of this embodiment, the coatings 210 and 220 are formed on at least one part of the head 171 of the bolt 170 and the recess 151 of the insulating member 150. This is a residual film of the film F1 that could not be removed. In the battery 100 of this embodiment, the number of parts is small. This is because the electrode terminals 50 and 60 are not divided into an external terminal and an internal terminal, as described in Japanese Patent Application Laid-Open No. 2004-133620. Therefore, there is no need to provide a caulking structure. Moreover, the electrode terminals 50 and 60 and the bus bar 190 can be suitably fastened.

  Note that this embodiment is merely an example, and does not limit the present invention. Therefore, the present invention can naturally be improved and modified in various ways without departing from the gist thereof. For example, if it is a battery, it can apply not only to a secondary battery but to a primary battery.

DESCRIPTION OF SYMBOLS 10 ... Winding electrode body 30 ... Positive electrode end part 40 ... Negative electrode end part 50 ... Positive electrode terminal 60 ... Negative electrode terminal 100 ... Battery 110 ... Battery container 120 ... Battery container main body 130 ... Cover body 150,160 ... Insulating member 151 ... Recess 170 , 180 ... bolts 210, 220 ... coating 1000, 2000 ... mold BP ... battery pack F1 ... coating P ... positive electrode plate P1 ... positive electrode coating part P2 ... positive electrode non-coating part N ... negative electrode plate N1 ... negative electrode coating part N2 ... Negative electrode non-coated part S, T ... Separator

Claims (8)

An electrode body as a power generation element;
An electrode terminal electrically connected to the electrode body and provided with a through hole;
A battery container body for accommodating the electrode body and the electrolyte therein;
A lid joined to the battery case body;
An insulating member that insulates the electrode terminal and the lid and is provided with a recess;
A battery including a head disposed in the recess and a bolt including a screw shaft penetrating the through hole,
The lid and the electrode terminal are integrally formed through the insulating member,
At least one part of the surface of the head of the bolt and the surface of the recess of the insulating member,
A battery having a film formed thereon. The battery according to claim 1,
The material of the coating is
It is a resin that dissolves in a given solvent,
The material of the insulating member is:
A battery comprising a material that does not dissolve in the predetermined solvent. The battery according to claim 2,
The material of the resin that dissolves in the predetermined solvent is:
A battery characterized by being made of any material selected from polycarbonate, polyvinyl chloride, and polypropylene. An electrode body creation process for creating an electrode body as a power generation element;
A structure creation step of creating a structure by integrating a lid, an electrode terminal, and a bolt via an insulating member;
A battery manufacturing method including a step of creating a single cell by disposing the electrode body inside a battery container and injecting an electrolyte solution and sealing the structure with the structure,
The structure creating step includes
A film forming step of forming a film with a first resin on the head of the bolt;
An insulating member forming step of forming an insulating member by integrating the coating of the bolt, the lid, and the electrode terminal;
A method for producing a battery, comprising: a coating removal step for removing the coating. A method of manufacturing a battery according to claim 4,
In the film removal step,
A method for producing a battery, wherein a solvent that dissolves the coating and does not dissolve the insulating member is used. A method of manufacturing a battery according to claim 5,
The solvent used in the film removal step is
A method of manufacturing a battery, which is also a cleaning liquid for cleaning the structure. A method of manufacturing a battery according to claim 5 or 6,
The combination of the first resin and the solvent is respectively
A method for producing a battery, which is one of a combination of polycarbonate and acetone, polyvinyl chloride and acetone, polypropylene and acetone, polyvinyl chloride and ethanol. A method of manufacturing a battery according to any one of claims 4 to 7,
A method for producing a battery, comprising a step of creating an assembled battery by fastening an electrode terminal of the single battery and a bus bar.

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