JP5369841B2 - Battery manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing a battery with manufacturing cost reduced and with a sealing property improved between a case lid member and an electrode terminal member. <P>SOLUTION: The method for manufacturing a lithium secondary battery 100 includes a first molding process of preliminarily forming an inside resin body 131 made of insulating first resin on an outer periphery face 121d of a terminal coating part 121 out of an electrode terminal member 120, and a second molding process of forming an outside resin body 135 combined with the inner resin body 131 by insert molding by injecting insulating second resin between a case lid member 113 and the electrode terminal member 120 with the electrode terminal member 120 in an inserted state into a terminal insertion hole 113h of the case lid member 113 and forming a resin insulating member 130. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a battery manufacturing method including a metal case lid member having a terminal insertion hole and a metal electrode terminal member that is inserted into the terminal insertion hole and fixed to the case lid member. The present invention relates to a method of manufacturing a battery including a resin insulating member that is interposed between a case lid member and an electrode terminal member and insulates between them.

  Conventionally, a metal case lid member having a terminal insertion hole, a metal electrode terminal member inserted into the terminal insertion hole and fixed to the case lid member, and between the case lid member and the electrode terminal member A battery including a resin insulating member that interposes and insulates them is known. The case lid member, the electrode terminal member, and the resin insulating member can be integrally formed by resin insert molding.

  An example of such a battery is a battery 900 shown in FIGS. 12 and 13. The battery 900 includes a metal case body member 911 having a box shape (bottomed rectangular tube shape) and a metal case lid member 913 having a rectangular plate shape welded so as to close the opening. A battery case 910 is provided. The case lid member 913 is provided with terminal insertion holes 913h and 913h in the vicinity of both ends in the longitudinal direction. Metal terminal member 920 and 920 are inserted through these terminal insertion holes 913h and 913h, respectively. These electrode terminal members 920 and 920 are fixed to the case lid member 913 via resin insulation members 930 and 930, respectively.

  In such a battery 900, a minute interface gap may occur at the interface between the case lid member 913 and the resin insulating members 930 and 930, or at the interface between the electrode terminal members 920 and 920 and the resin insulating members 930 and 930. Depending on the usage environment and the like, the interface gap between the case lid member 913 or the electrode terminal members 920 and 920 and the resin insulating members 930 and 930 may increase. Then, moisture or the like may enter the interface gap and the resin insulating members 930 and 930 may deteriorate due to hydrolysis or the like. As a method for solving this problem, there is a method in which the above-mentioned interfacial gap is filled with a filler that can follow the fluctuation of the interfacial gap. For example, Patent Document 1 discloses such a method.

Japanese Patent Laid-Open No. 10-100191

  However, in the above method, since the case lid member, the electrode terminal member, and the resin insulating member are integrally formed by resin insert molding, the filler is filled into the minute interfacial gap generated there, so that the number of steps is reduced. The manufacturing process becomes complicated by increasing the number. For this reason, a manufacturing cost starts.

  Here, in the battery 900, the case lid member 913, the electrode terminal members 920 and 920, and the resin insulating members 930 and 930 can be integrally formed by resin insert molding. Specifically, the electrode terminal members 920 and 920 are inserted through the terminal insertion holes 913h and 913h of the case lid member 913, respectively, and insert molding is performed between the case lid member 913 and the electrode terminal members 920 and 920. Resin is injected to form resin insulation members 930 and 930 (see FIGS. 14 to 17). 14 to 17, only the vicinity of one electrode terminal member 920 is shown. In FIG. 14, only the mold KA9 is shown among three types of molds KA9, KB9, and KC9 described later, and the molds KB9 and KC9 are not shown.

Specifically, first, as shown in FIGS. 14 and 15, the case cover member 913 and the electrode terminal member are inserted in the state where the electrode terminal members 920 and 920 are inserted into the terminal insertion holes 913 h and 913 h of the case cover member 913, respectively. 920 and 920 are held by three types of molds (slide mold KA9, movable mold KB9, and fixed mold KC9).
Among these, the fixed mold KC9 is a mold fixed at a predetermined position, and comes into contact with a predetermined portion of the back surface 913b of the case lid member 913 from below. The movable mold KB9 is a mold that can move in the vertical direction, and comes into contact with a predetermined portion of the surface 913a of the case lid member 913 from above. The slide molds KA9 and KA9 are movable molds in the horizontal direction (left and right direction in FIGS. 14 and 15), and are placed on a predetermined portion of the electrode terminal member 920 from the left side and the right side in FIGS. The electrode terminal member 920 is pinched in contact.

  Thereafter, resin is injected between the case lid member 913 and the electrode terminal member 920 (a space surrounded by the slide mold KA9, the movable mold KB9, and the fixed mold KC9). When the resin is cooled after the injection, a resin insulating member 930 that connects the case lid member 913 and the electrode terminal member 920 is formed as shown in FIGS. 16 and 17. By such an insert molding process, the case lid member 913, the electrode terminal members 920 and 920, and the resin insulating members 930 and 930 are integrally formed.

  However, in the above-described insert molding process, the resin injected at the time of insert molding may be cooled unevenly due to heat pulling by the case lid member 913 or the electrode terminal member 920, and the resin insulating member 930 Large residual stress may occur. As a result, the adhesiveness (sealability) between the case lid member 913 or the electrode terminal member 920 and the resin insulating member 930 may be reduced. In addition, a crack may occur in the resin insulating member 930 itself, which may reduce the sealing performance between the case lid member 913 and the electrode terminal member 920.

  The present invention has been made in view of the current situation, and includes a case lid member having a terminal insertion hole, an electrode terminal member inserted into the terminal insertion hole, and a case lid member and an electrode terminal member. In addition, in a battery including a resin insulating member that insulates between them, a manufacturing method of the battery that can reduce the manufacturing cost and improve the sealing performance between the case lid member and the electrode terminal member is provided. For the purpose.

The solution includes a case lid member made of metal and having a terminal insertion hole penetrating itself, an electrode terminal member made of metal and inserted into the terminal insertion hole and fixed to the case lid member, and an insulating member. Made of a conductive resin, interposed at least between the case lid member and the electrode terminal member to insulate between them, and in close contact with the electrode terminal member inside itself, and on the outside of the case lid member A first insulating portion including a peripheral surface of a hole arrangement portion to be arranged in the terminal insertion hole, of the electrode terminal member; and A first molding step of forming a first resin body made of an insulating first resin in advance in at least one of the second predetermined portions including the inner peripheral surface of the terminal insertion hole in the case lid member; After the first molding step, In the state where the electrode terminal member is inserted into the terminal insertion hole of the case lid member, an insulating second resin is injected between the case lid member and the electrode terminal member by insert molding, Forming a second resin body bonded to one resin body, and forming a resin insulation member having the first resin body and the second resin body, and in the first molding step, The first resin body is formed at least on the first predetermined portion of the electrode terminal member, and in the second molding step, the electrode terminal member is formed on the electrode terminal member without being directly held by a mold. In the battery manufacturing method, the insert molding is performed while the first resin body is held by a mold .

  In the battery manufacturing method of the present invention, the first resin body is formed in advance in the first molding step prior to the insert molding in the second molding step. For this reason, in the second molding step, since the injected second resin is in contact with the first resin body, heat shrinkage due to the case lid member and the electrode terminal member can be reduced as compared with the conventional case, It can suppress that the cooling of 2nd resin becomes non-uniform | heterogenous than before. Therefore, the residual stress generated in the resin insulating member (particularly the second resin body) can be reduced.

Thereby, the adhesiveness (sealability) between the case lid member and the electrode terminal member and the resin insulating member can be improved. Moreover, since it becomes difficult to produce a crack in resin insulation member itself, the sealing performance between a case cover member and an electrode terminal member can be improved also in this respect. Furthermore, according to the manufacturing method of the present invention, since the case lid member, the electrode terminal member, and the resin insulating member are integrally formed by insert molding, it is not necessary to fill the interfacial gap with a filler, thereby simplifying the manufacturing process. Manufacturing costs can be reduced.
The “first resin” and the “second resin” may be different resins or the same resin.

In the insert molding of the second molding step, when the electrode terminal member is directly held by a mold, metal powder or the like may be generated from the electrode terminal member due to biting or the like. As a result, the metal foreign matter may enter the battery and cause a short circuit or the like.
In contrast, in the manufacturing method of the present invention, the first resin body is formed on the electrode terminal member in the first molding step, and the electrode terminal member is not directly held by the mold in the second molding step. 1 Hold the resin body with a mold. For this reason, it can prevent that metal powder etc. arise from an electrode terminal member, and can prevent that a metal foreign material mixes in a battery. Therefore, a highly reliable battery can be manufactured.

1 is a perspective view of a lithium secondary battery according to Embodiment 1. FIG. It is a longitudinal cross-sectional view of the case cover member, the electrode terminal member, and the resin insulation member which were integrally formed by insert molding among the lithium secondary batteries according to Embodiment 1, and is a cross-sectional view along AA in FIG. It is explanatory drawing which shows a mode that the inner side resin body was formed in the electrode terminal member in the 1st shaping | molding process regarding the manufacturing method of the lithium secondary battery which concerns on Embodiment 1. FIG. It is explanatory drawing which looked at a mode that a case cover member and an electrode terminal member are hold | maintained with a metal mold | die (slide metal mold | die) in a 2nd shaping | molding process regarding the manufacturing method of the lithium secondary battery which concerns on Embodiment 1. FIG. FIG. 5 shows how the case lid member and the electrode terminal member are held by the molds (slide mold, movable mold and fixed mold) in the second molding step in the method for manufacturing the lithium secondary battery according to the first embodiment. It is explanatory drawing seen in the longitudinal cross-section corresponding to the BB cross section of 4. FIG. It is explanatory drawing which looked at a mode that the outer side resin body was formed and the resin insulation member was formed in the 2nd shaping | molding process regarding the manufacturing method of the lithium secondary battery which concerns on Embodiment 1 from upper direction. Regarding the method for manufacturing a lithium secondary battery according to Embodiment 1, in the second molding step, a state in which the outer resin body is formed and the resin insulating member is formed is seen in a longitudinal section corresponding to the CC section of FIG. FIG. It is explanatory drawing which shows a mode that the outer side resin body was formed in the case cover member in the 1st shaping | molding process regarding the manufacturing method of the lithium secondary battery which concerns on a reference form . It is explanatory drawing which looked at a mode that a case cover member and an electrode terminal member are hold | maintained with a metal mold | die (slide metal mold | die) in a 2nd shaping | molding process regarding the manufacturing method of the lithium secondary battery which concerns on a reference form . FIG. 9 shows a state in which the case lid member and the electrode terminal member are held by the molds (slide mold, movable mold and fixed mold) in the second molding step with respect to the method for manufacturing the lithium secondary battery according to the reference embodiment . It is explanatory drawing seen in the longitudinal cross-section corresponding to DD cross section. It is explanatory drawing which looked at the mode which formed the inner side resin body and formed the resin insulation member in the 2nd shaping | molding process regarding the manufacturing method of the lithium secondary battery which concerns on a reference form in the longitudinal cross-section. It is a perspective view of the lithium secondary battery which concerns on a prior art. It is a longitudinal cross-sectional view of the case cover member, electrode terminal member, and resin insulation member which were integrally formed by insert molding among the lithium secondary batteries which concern on a prior art, and is EE sectional drawing in FIG. It is explanatory drawing which looked at a mode that a case cover member and an electrode terminal member are hold | maintained by a metal mold | die (slide metal mold | die) in an insert molding process regarding the manufacturing method of the battery which concerns on a prior art. FIG. 14 shows a state in which the case lid member and the electrode terminal member are held by the molds (slide mold, movable mold and fixed mold) in the insert molding process. It is explanatory drawing seen in the longitudinal cross-section corresponding to a cross section. It is explanatory drawing which looked at a mode that the resin insulation member was formed in the insert molding process from the upper direction regarding the manufacturing method of the battery which concerns on a prior art. It is explanatory drawing which looked at the mode which formed the resin insulation member in the insert molding process in the insert molding process in the longitudinal cross-section corresponding to the GG cross section of FIG. 16 regarding the manufacturing method of the battery which concerns on a prior art.

(Embodiment 1)
Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows a lithium secondary battery (battery) 100 according to the first embodiment. FIG. 2 shows an integrated case lid member 113, electrode terminal member 120, and resin insulating member 130 in the lithium secondary battery 100. 1 and FIG. 2 is described with the upper side of the lithium secondary battery 100 as the upper side and the lower side of the lithium secondary battery 100 as the lower side.

  The lithium secondary battery 100 is a prismatic battery that is mounted on a vehicle such as a hybrid car or an electric vehicle, or a battery-powered device such as a hammer drill. A lithium secondary battery 100 includes a rectangular battery case 110, an electrode body (not shown) housed in the battery case 110 (a power generation element), two electrode terminal members 120 and 120 supported by the battery case 110, and a battery case. 110 and electrode terminal members 120, 120 are formed of resin insulating members 130, 130 that insulate between the electrode terminal members 120, 120. In addition, an electrolytic solution is injected into the battery case 110.

Among these, the battery case 110 is made of metal (specifically, pure aluminum) and is formed in a rectangular parallelepiped shape. The battery case 110 has a box shape (bottomed rectangular tube shape) that is open only on the upper side, and is welded in a form that closes the case body member 111 that houses the electrode body and the opening 111h of the case body member 111. A rectangular plate-shaped case lid member 113 is included.
The case body member 111 includes a rectangular plate-like case bottom wall portion 111b facing the case lid member 113, and four rectangular plate-like case side wall portions 111c connecting the case lid member 113 and the case bottom wall portion 111b, 111c,...

  The case lid member 113 is made of metal (pure aluminum in the first embodiment) and has a rectangular plate shape having a front surface 113a and a back surface 113b. In the case lid member 113, terminal insertion holes 113h and 113h having a rectangular shape in a plan view penetrating through the case lid member 113 are formed at predetermined positions near both ends in the longitudinal direction (in addition to FIG. 1, (See also FIG. 2). The electrode terminal member 120 for positive electrode (left side in FIG. 1) is inserted into one terminal insertion hole 113h, and the electrode terminal member 120 for negative electrode (right side in FIG. 1) is inserted into the other terminal insertion hole 113h. Is inserted.

  A non-returnable safety valve portion 117 having a rectangular shape in plan view is provided at the center in the longitudinal direction of the case lid member 113. The safety valve portion 117 is formed integrally with the case lid member 113 and forms a part of the case lid member 113. In the safety valve portion 117, a groove portion 117v forming a V-shaped groove is formed in a predetermined shape. The safety valve 117 is activated and opened when the internal pressure inside the battery case 110 reaches a predetermined pressure. That is, when the internal pressure reaches a predetermined pressure, the safety valve portion 117 is broken starting from the groove portion 117v, and the gas inside the battery is released to the outside of the battery.

  Next, the electrode terminal members 120 and 120 will be described. The electrode terminal member 120 for the positive electrode is electrically and mechanically connected to the positive electrode current collector foil of the electrode body inside the battery case 110, while the terminal insertion hole 113h formed in the battery case 110 (the case lid member 113). Through the battery case 110 (on the case lid member 113). Further, the electrode terminal member 120 for the negative electrode is electrically and mechanically connected to the negative electrode current collector foil of the electrode body inside the battery case 110, while the terminal insertion formed in the battery case 110 (the case lid member 113). It extends outside the battery case 110 (on the case lid member 113) through the hole 113h. These electrode terminal members 120 and 120 are made of metal (pure copper in the first embodiment).

  These electrode terminal members 120 and 120 are fixed to the case lid member 113 via resin insulation members 130 and 130, respectively. The resin insulating member 130 is made of resin (in this embodiment 1, PPS resin). The resin insulating member 130 has a substantially cylindrical shape, is interposed between the case lid member 113 (terminal insertion hole 113h) and the electrode terminal member 120, and extends from the inside of the battery case 110 to the outside. The resin insulating member 130 is in close contact with the electrode terminal member 120 inside itself, and is in close contact with the case lid member 113 outside itself to connect the electrode terminal member 120 and the case lid member 113, and the electrode terminal member 120 and the case lid member 113 are electrically insulated.

More specifically, the resin insulating member 130 includes an inner resin body 131 and an outer resin body 135. In the first embodiment, the inner resin body 131 corresponds to the first resin body of the present invention, and the outer resin body 135 corresponds to the second resin body of the present invention.
Among these, the inner side resin body 131 has a rectangular tube shape, and covers the outer peripheral surface 121 d of the terminal covering portion 121 of the electrode terminal member 120 and is in close contact therewith. The outer peripheral surface 121d of the terminal covering portion 121 is on the outer peripheral surface 121ed of the hole arrangement portion 121e arranged in the terminal insertion hole 113h of the case lid member 113 and on the upper side (outside of the battery case 110) of the hole arrangement portion 121e. The outer peripheral surface 121fd of the upper side portion 121f located and the outer peripheral surface 121gd of the lower side portion 121g located on the lower side (inside the battery case 110) of the hole placement portion 121e. In the first embodiment, the outer peripheral surface 121d of the terminal covering portion 121 corresponds to the first predetermined portion of the present invention.

  The outer resin body 135 has a cylindrical shape, covers the periphery of the inner resin body 131, and covers the lid covering surface 113d of the case lid member 113 on the outer side thereof so as to be in close contact therewith. More specifically, the outer resin body 135 covers the periphery of the inner resin body 131 with the upper resin portion 131s of the inner resin body 131 protruding upward. Further, the cover covering surface 113d to which the outer resin body 135 is in close contact with the inner peripheral surface 113hn of the terminal insertion hole 113h and the surface hole peripheral portion 113ad that forms the periphery of the terminal insertion hole 113h out of the surface 113a of the case cover member 113. Of the back surface 113b of the case lid member 113, the back surface hole peripheral portion 113bd is formed around the terminal insertion hole 113h.

  Next, a method for manufacturing the lithium secondary battery 100 will be described (see FIGS. 3 to 7). First, electrode terminal members 120 and 120 are prepared. In the first molding step, an inner resin body 131 made of an insulating first resin is formed on the outer peripheral surface (first predetermined portion) 121d of the terminal covering portion 121 in the electrode terminal member 120 (see FIG. 3). ). Specifically, a rectangular cylindrical inner resin body is formed on the outer peripheral surface 121d of the terminal covering portion 121 of the electrode terminal member 120 by resin insert molding using an insulating first resin (in this embodiment, PPS resin). 131 is formed.

  Next, a 2nd shaping | molding process is performed. That is, the case lid member 113 is prepared. Then, in a state where the electrode terminal members 120 and 120 are inserted into the respective terminal insertion holes 113h and 113h of the case lid member 113, an insulating property is provided between the case lid member 113 and the electrode terminal members 120 and 120 by insert molding. The second resin is injected to form the outer resin bodies 135 and 135 coupled to the inner resin bodies 131 and 131, and the resin insulating members 130 and 130 made of the inner resin body 131 and the outer resin body 135 are formed (FIG. 4 to FIG. 4). (See FIG. 7). 4-7, only the vicinity of one electrode terminal member 120 is shown. 4 and 6, only the mold KA1 is shown among the three types of molds KA1, KB1, and KC1 described later, and the molds KB1 and KC1 are not shown.

Specifically, first, as shown in FIGS. 4 and 5, the case lid member 113 and the electrode terminal in a state where the electrode terminal members 120 and 120 are inserted into the terminal insertion holes 113 h and 113 h of the case lid member 113, respectively. The members 120 and 120 are held by three types of molds (slide mold KA1, movable mold KB1, and fixed mold KC1).
Among these, the fixed mold KC1 is a mold fixed at a predetermined position. The fixed mold KC1 abuts from below on the back surface outer peripheral portion 113be that forms the periphery of the back surface hole peripheral portion 113bd in the back surface 113b of the case lid member 113. The fixed mold KC1 also comes into contact with the radially outer portion of the lower end surface 131kn of the inner resin body 131 from below. On the other hand, the fixed mold KC1 is separated from the electrode terminal member 120 via a slight gap L2.

  The movable mold KB1 is a mold that can move in the vertical direction. The movable mold KB1 abuts on the surface outer peripheral portion 113ae surrounding the surface hole peripheral portion 113ad from the upper side of the surface 113a of the case lid member 113 from above. As a result, the case lid member 113 is held between the fixed mold KC1 and the movable mold KB1. The movable mold KB1 also comes into contact with the radially outer portion of the upper end surface 131sn of the inner resin body 131 from above. On the other hand, the movable mold KB1 is separated from the electrode terminal member 120 via a slight gap L1. The movable die KB1 is provided with a die insertion hole KB1h through which the slide die KA1 can be inserted.

  The slide mold KA1 is a mold that can move in the horizontal direction (left and right directions in FIGS. 4 and 5), and has two slide molds KA1 and KA1 for one electrode terminal member 120. The slide molds KA1 and KA1 are respectively inserted into the mold insertion holes KB1h and KB1h of the movable mold KB1 and come into contact with the resin upper part 131s of the inner resin body 131 from the left side and the right side in FIGS. The upper resin portion 131s of the inner resin body 131 is sandwiched. Accordingly, the inner resin body 131 and the electrode terminal member 120 integrated with the inner resin body 131 are held in the slide mold KA1.

  In the first embodiment, since the slide molds KA1 and KA1 do not directly contact the electrode terminal member 120, the slide molds KA1 and KA1 do not directly hold the electrode terminal member 120. Therefore, it is possible to reliably prevent metal powder or the like from being generated from the electrode terminal member 120 due to biting by the slide molds KA1 and KA1.

Thereafter, an insulating second resin (in the first embodiment, PPS) is interposed between the case lid member 113 and the electrode terminal member 120 (a space surrounded by the slide mold KA1, the movable mold KB1, and the fixed mold KC1). Resin). When the second resin is cooled after the injection, as shown in FIGS. 6 and 7, an outer resin body 135 bonded to the inner resin body 131 is formed, and the inner resin body 131 and the outer resin body 135 are separated from each other. A resin insulating member 130 is formed. At that time, since the second resin is in contact with the inner resin body 131, the heat shrinkage can be reduced, and thus the second resin can be prevented from being non-uniformly cooled compared to the conventional case. As a result, the residual stress generated in the resin insulating member 130 (particularly the outer resin body 135) can be reduced.
By this second molding step, as shown in FIG. 2, the case lid member 113, the electrode terminal members 120, 120, and the resin insulating members 130, 130 are integrally formed.

  After finishing the second molding step, an electrode body is prepared, and the positive electrode terminal member 120 and the negative electrode terminal member 120 are welded to both ends of the electrode body in the axial direction. Next, among these, the electrode body is inserted into a separately prepared case body member 111, and the case lid member 113 is disposed on the opening 111 h of the case body member 111. Then, the periphery of the case lid member 113 and the opening periphery of the case body member 111 are laser-welded. Thereafter, an electrolytic solution is injected into the battery case 110 from a liquid injection port (not shown) of the case lid member 113. Thus, the lithium secondary battery 100 is completed.

  As described above, in the method for manufacturing the lithium secondary battery 100 according to the first embodiment, the inner resin body 131 is previously attached to the electrode terminal member 120 in the first molding step prior to the insert molding in the second molding step. Forming. For this reason, since it can suppress that the inject | pouring 2nd resin cools unevenly compared with the case where this inner side resin body 131 does not exist at the time of insert molding of a 2nd shaping | molding process, the resin insulation member 130 ( In particular, the residual stress generated in the outer resin body 135) can be reduced.

  Thereby, the adhesiveness (sealability) between the case lid member 113 and the electrode terminal members 120 and 120 and the resin insulating members 130 and 130 can be improved. Further, since cracks are hardly generated in the resin insulating member 130 itself, the sealing performance between the case lid member 113 and the electrode terminal members 120 and 120 can be improved in this respect as well. In the manufacturing method of the first embodiment, after the case lid member 113, the electrode terminal members 120 and 120, and the resin insulating members 130 and 130 are integrally formed by insert molding, a filler is added to the interfacial gap as in the conventional case. Since it is not necessary to fill, the manufacturing process can be simplified and the manufacturing cost can be reduced.

  Furthermore, in the manufacturing method of the first embodiment, the inner resin body 131 is formed on the electrode terminal member 120 in the first molding step, and the electrode terminal member 120 is directly held by the slide molds KA1 and KA1 in the second molding step. Without this, the inner resin body 131 and the electrode terminal member 120 are held by holding the inner resin body 131 with the slide molds KA1 and KA1. For this reason, it is possible to reliably prevent metal powder or the like from being generated from the electrode terminal member 120 due to biting by the slide molds KA1 and KA1, and it is possible to reliably prevent metal foreign matter from being mixed into the lithium secondary battery 100. Therefore, the lithium secondary battery 100 with high reliability can be manufactured.

( Reference form )
Next, a reference form will be described. The lithium secondary battery 100 of the present embodiment is the same form as the lithium secondary battery 100 of the first embodiment, but the manufacturing method thereof, specifically, the method of forming the resin insulating member 130 is the first embodiment. And different. Other than that, it is basically the same as in the first embodiment, and therefore the description of the same parts as in the first embodiment is omitted or simplified.

A method for manufacturing the lithium secondary battery 100 according to this embodiment will be described (see FIGS. 8 to 11). In this reference embodiment , first, a case lid member 113 is prepared. In the first molding step, outer resin bodies 135 and 135 made of an insulating first resin are formed on the lid covering surfaces 113d and 113d of the case lid member 113 (see FIG. 8). Specifically, the outer resin bodies 135 and 135 are formed on the lid covering surfaces 113d and 113d of the case lid member 113 by resin insert molding using an insulating first resin (in this embodiment , PPS resin). In the present embodiment , the lid covering surface 113d of the case lid member 113 corresponds to the second predetermined portion of the present invention, and the outer resin body 135 corresponds to the first resin body of the present invention.

  Next, a 2nd shaping | molding process is performed. That is, electrode terminal members 120 and 120 are prepared. Then, the case lid member 113 and the electrode terminal member are formed by insert molding in a state where the electrode terminal members 120 and 120 are respectively inserted into the terminal insertion holes 113h and 113h (inside the outer resin bodies 135 and 135) of the case lid member 113. The second resin is injected between 120 and 120 to form the inner resin bodies 131 and 131 that are coupled to the outer resin bodies 135 and 135, and the resin insulating members 130 and 130 that are composed of the outer resin body 135 and the inner resin body 131. (See FIGS. 9 to 11). 9 to 11, only the vicinity of one electrode terminal member 120 is shown. In FIG. 9, only the mold KA2 is shown among the three types of molds KA2, KB2, and KC2, which will be described later, and the molds KB2 and KC2 are not shown.

Specifically, first, as shown in FIGS. 9 and 10, the electrode terminal members 120 and 120 were inserted into the terminal insertion holes 113h and 113h (inside the outer resin bodies 135 and 135) of the case lid member 113, respectively. In this state, the case lid member 113 and the electrode terminal members 120 and 120 are held by three types of molds (slide mold KA2, movable mold KB2, and fixed mold KC2).
Among these, the fixed mold KC2 is a mold fixed at a predetermined position. The fixed mold KC2 comes into contact with the rear outer peripheral portion 113be of the rear surface 113b of the case lid member 113 from below. In addition, the fixed mold KC2 also contacts the lower portion 122 of the terminal cover 121 of the electrode terminal member 120 from the outside in the radial direction.

  The movable mold KB2 is a mold that can move in the vertical direction. This movable mold KB2 abuts on the outer surface peripheral portion 113ae of the surface 113a of the case lid member 113 from above. As a result, the case lid member 113 is held between the fixed mold KC2 and the movable mold KB2. On the other hand, the movable mold KB2 is separated from the electrode terminal member 120 via a slight gap L3. The movable die KB2 is provided with a die insertion hole KB2h through which the slide die KA2 can be inserted.

  The slide mold KA2 is a mold that can move in the horizontal direction (left and right directions in FIGS. 9 and 10), and has two slide molds KA2 and KA2 for one electrode terminal member 120. The slide molds KA2 and KA2 are respectively inserted into the mold insertion holes KB2h and KB2h of the movable mold KB2, and the electrode terminal member 120 has an upper portion 123 positioned on the upper side of the terminal covering portion 121. 9 and FIG. 10, the upper part 123 of the electrode terminal member 120 is held between the left side and the right side. Thereby, the electrode terminal member 120 is hold | maintained at slide metal mold | die KA2, KA2.

Thereafter, an insulating second resin (PPS resin in the present embodiment ) is inserted between the case lid member 113 and the electrode terminal member 120 (a space surrounded by the slide mold KA2, the movable mold KB2, and the fixed mold KC2). ). After the injection, when the second resin is cooled, as shown in FIG. 11, an inner resin body 131 that is bonded (thermally melted) to the outer resin body 135 is formed, and the resin insulation composed of the outer resin body 135 and the inner resin body 131 is formed. Member 130 is formed. At this time, since the second resin is in contact with the outer resin body 135, heat shrinkage can be alleviated, so that it is possible to suppress the cooling of the second resin from becoming nonuniform. As a result, the residual stress generated in the resin insulating member 130 (particularly the inner resin body 131) can be reduced.
After the second molding step, the lithium secondary battery 100 is completed in the same manner as in the first embodiment.

As described above, in the method for manufacturing the lithium secondary battery 100 according to the present embodiment , the outer resin body 135 is formed on the case lid member 113 in advance in the first molding step prior to the insert molding in the second molding step. doing. For this reason, in the case of insert molding in the second molding step, it is possible to prevent the injected second resin from being cooled unevenly as compared with the case where the outer resin body 135 is not provided. In particular, the residual stress generated in the inner resin body 131) can be reduced.

Thereby, the adhesiveness (sealability) between the case lid member 113 and the electrode terminal members 120 and 120 and the resin insulating members 130 and 130 can be improved. Further, since cracks are hardly generated in the resin insulating member 130 itself, the sealing performance between the case lid member 113 and the electrode terminal members 120 and 120 can be improved in this respect as well. In the manufacturing method of the present embodiment , the case lid member 113, the electrode terminal members 120 and 120, and the resin insulating members 130 and 130 are integrally formed by insert molding, and then the interfacial gap is filled as in the conventional case. Therefore, the manufacturing process can be simplified and the manufacturing cost can be reduced. In addition, the same parts as those of the first embodiment have the same effects as those of the first embodiment.

In the above, the present invention has been described with reference to the embodiment. However, the present invention is not limited to the above-described first embodiment , and it is needless to say that the present invention can be appropriately modified and applied without departing from the gist thereof.
For example, in the first embodiment and the reference embodiment , the first resin and the second resin are the same resin (specifically, PPS resin), but the adhesion to the case lid member 113 and the electrode terminal member 120, the case lid, In consideration of the difference in thermal expansion coefficient from the member 113 and the electrode terminal member 120, different resins can be used.

100 Lithium secondary battery (battery)
110 battery case 111 case main body member 113 case lid member 113d lid covering surface (second predetermined portion)
113h Terminal insertion hole 120 Electrode terminal member 121 Terminal covering portion 121d Outer peripheral surface (first predetermined portion)
121e hole arrangement part 121ed outer peripheral surface 130 resin insulation member 131 inner side resin body (1st resin body, 2nd resin body)
131s Resin upper part 135 Outer resin body (second resin body, first resin body)
KA1, KA2 Slide mold KB1, KB2 Movable mold KB1h, KB2h Mold insertion hole KC1, KC2 Fixed mold

Claims (1)

A case lid member made of metal and having a terminal insertion hole penetrating itself,
An electrode terminal member made of metal, inserted into the terminal insertion hole and fixed to the case lid member,
It is made of an insulating resin and is interposed between at least the case lid member and the electrode terminal member to insulate between them, and is in close contact with the electrode terminal member inside itself, and the case lid outside itself A resin insulation member in close contact with the member, comprising:
Among the electrode terminal members, a first predetermined portion including an outer peripheral surface of a hole arrangement portion to be arranged in the terminal insertion hole, and an inner peripheral surface of the terminal insertion hole among the case lid member. A first molding step of forming a first resin body made of an insulating first resin in advance in at least one of the second predetermined portions;
After the first molding step, an insulating second resin is formed between the case lid member and the electrode terminal member by insert molding in a state where the electrode terminal member is inserted into the terminal insertion hole of the case lid member. And forming a second resin body bonded to the first resin body and forming the resin insulating member having the first resin body and the second resin body, and a second molding step ,
In the first molding step,
Forming the first resin body at least on the first predetermined portion of the electrode terminal member;
In the second molding step,
The method for manufacturing a battery , wherein the insert molding is performed while holding the first resin body formed on the electrode terminal member with a mold without directly holding the electrode terminal member with a mold .

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