JP4904863B2 - Battery module and manufacturing method thereof - Google Patents

Description

  The present invention relates to a battery module and a manufacturing method thereof.

A flat thin battery (hereinafter, referred to as a flat thin battery) in which a power generation element constituted by laminating positive and negative electrode plates is sealed with an exterior material such as a laminate film, and a plate-like electrode terminal is led out from the exterior material. “Flat battery” is known. In recent years, by stacking a plurality of such flat batteries and electrically connecting each flat battery in series and / or in parallel (hereinafter referred to as “series-parallel”), a high output and high capacity battery module. (See Patent Document 1).
JP 2001-256934 A

  However, in the battery module described in Patent Document 1, in order to position and stack a plurality of flat batteries in the case, a groove-shaped guide that can guide the peripheral portion of the flat battery on the inner wall surface of the case. The part is provided in a plurality of rows. For this reason, not only the structure of the case is complicated, but also in manufacturing the battery module, each flat battery is inserted into the case one by one while inserting the peripheral edge of the flat battery into the groove-shaped guide portion on the inner wall of the case. There was a problem that it had to be accommodated and was forced to perform extremely complicated work.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a battery module that can easily and surely position a plurality of flat batteries in a case and has high productivity. It is in.

  The above object of the present invention is achieved by the following means.

  (1) The power generation element is sealed with an exterior material, and a plurality of flat batteries each having a plate-like electrode terminal led out from the exterior material are stacked, and the electrode terminals of each flat battery are electrically connected to each other. A battery module having a case that forms an outer frame and has a plate shape that sandwiches the electrode terminals from both sides of the electrode terminals along a direction in which the plurality of flat batteries are stacked An insulating plate, and a hollow member provided through the insulating plate, the hollow member receiving a tightening axial force when tightened in the axial direction using a shaft member inserted through the insulating plate. The battery module is characterized in that the hollow member is provided with engagement means for engaging the hollow members adjacent in the axial direction so that the axial centers thereof coincide with each other.

  (2) Sealing the power generation element with an exterior material and laminating a plurality of flat type batteries in which plate-like electrode terminals are led out from the exterior material to electrically connect the electrode terminals of each flat type battery The battery module is manufactured by connecting to a plurality of flat batteries, and is clamped in the axial direction from both sides of the electrode terminal along a direction in which the plurality of flat batteries are stacked, using a shaft member inserted inside. A plurality of flat batteries in which each electrode terminal is sandwiched between the insulating plates and stacked, and sandwiched by a plate-like electrically insulating insulating plate embedded with a hollow member that receives a tightening axial force. And in the clamping step, the engaging means provided on the hollow member engage with each other so that the axially adjacent hollow members coincide with each other in the axial direction. The electric device characterized by engaging Method of manufacturing the module.

  According to the present invention, when the electrode terminal is sandwiched between the insulating plates, the engagement means provided on the hollow member is engaged so that the axially adjacent hollow members are aligned with each other. Engage. Thus, the hollow members arranged in the axial direction are engaged with each other, whereby the plurality of insulating plates are reliably positioned and prevented from being individually displaced.

  Therefore, it is possible to easily and reliably position a plurality of flat batteries in a case in a state where each electrode terminal is securely sandwiched between laminated insulating plates, and to provide a battery module with high productivity. Become.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 is a perspective view showing an assembled battery 200 configured by combining a plurality of battery modules 50 according to an embodiment of the present invention, and FIG. 2 is a perspective view showing the battery module 50 shown in FIG. 3 is an exploded perspective view showing the battery module 50 shown in FIG. 2, and FIG. 4 is a perspective view showing an example of the battery 100 included in the cell unit main body 80 shown in FIG.

  As shown in FIG. 1, an assembled battery 200 corresponding to a desired current, voltage, and capacity can be formed by stacking an arbitrary number of battery modules 50 and connecting the battery modules 50 in series and parallel. In the example of FIG. 1, the assembled battery 200 includes twelve battery modules 50 arranged in three layers and four rows. When the battery modules 50 are connected in series and parallel, an appropriate connection member such as a bus bar is used. The assembled battery 200 is mounted on a vehicle that generates vibration, such as an automobile or a train.

  In the assembled battery 200, the plurality of battery modules 50 are stacked on the lower case 201 for the assembled battery. The plurality of stacked battery modules 50 are sandwiched and fixed between the lower case 201 and the restraining plate 202 by through bolts 203.

  As shown in FIGS. 2 and 3, the battery module 50 is housed in a case 70 in which a cell unit 60 including a plurality of (eight in the example of FIG. 3) batteries 100 forms an outer frame. FIG. 2 shows the battery module 50 upside down.

  Here, the X-axis direction shown in FIG. 2 is referred to as the longitudinal direction of the battery module 50, the cell unit 60, the case 70, and the like, and the Y-axis direction is referred to as the short direction. Further, in FIG. 2, a surface located on the front side in the longitudinal direction is a front surface, and a surface located on the far side in the longitudinal direction is a back surface. In the following description, the flat battery is simply referred to as “battery”.

  The case 70 includes a lower case 71 having a box shape in which an opening 71a is formed, and an upper case 72 forming a lid for closing the opening 71a. The edge 72a of the upper case 72 is wound around the edge 71c of the peripheral wall 71b of the lower case 71 by caulking (see the partially enlarged view of FIG. 1). The lower case 71 and the upper case 72 are formed from a relatively thin steel plate or aluminum plate, and are given a predetermined shape by pressing.

  The cell unit 60 includes a cell unit main body 80 in which eight batteries 100 are stacked and the batteries 100 are connected in series, and insulating covers 91 and 92 that are detachably attached to the front and back surfaces of the cell unit main body 80. , Including.

  As shown in FIG. 4, the battery 100 is, for example, a flat lithium ion secondary battery. It is sealed with a material 100a. In the battery 100, one end is electrically connected to the power generation element, and a tab-like tab 100t is led out from the exterior material 100a. The tab 100t extends on both sides (front side and back side) of the battery 100 in the longitudinal direction.

  The cell unit main body 80 further includes a spacer 110 (corresponding to an insulating plate) for sandwiching a tab 100t (corresponding to an electrode terminal) and positive and negative output terminals 140, 150. Here, the tab 100t is a general term for the plus-side tab 100p and the minus-side tab 100m.

  The positive and negative output terminals 140 and 150 are led out from the case 70 through a notch formed in a part of the peripheral wall 71 b of the lower case 71.

  In order to insert the bolts 203 through the case 70, bolt holes 73 are formed at four corners of the lower case 71 and the upper case 72. Reference numeral 94 denotes a cushioning material provided between the cell unit 60 and the upper case 72.

  As shown in FIG. 3, the spacer 110 is formed with an opening window 112 penetrating from the front surface to the back surface along the stacking direction. In the illustrated example, rectangular opening windows 112 are formed at two locations equally spaced on the left and right sides from the longitudinal center of the spacer 110. A part of the clamped tab 100t faces the opening window 112. The opening window 112 is used for a welding operation for electrical connection through the opening window 112.

  In the present embodiment, sleeves 93 (corresponding to hollow members) are fixedly provided at two locations of the spacer 110 so as to penetrate the spacer 110. The sleeve 93 is preferably formed (insert molding) by being embedded in the spacer 110 when the spacer 110 is molded. However, the sleeve 93 may be fixed to the hole formed in the spacer 110 with an adhesive or the like. Here, the sleeve 93 can receive a tightening axial force when it is tightened in the axial direction using a through bolt 203 as a shaft member inserted into the sleeve 93. The sleeve 93 is preferably made of a metal material such as aluminum or an aluminum alloy.

  5 is a schematic view of the laminated structure of the spacers 110 holding the tab 100t as viewed from the longitudinal direction, FIG. 6 is an enlarged cross-sectional view of part A in FIG. 5, and FIG. 7 is an enlarged view of part B in FIG. FIG.

  As shown in FIG. 5, in the present embodiment, eight tabs 100 t are positioned between each of the nine spacers 110.

  As shown in FIGS. 6 and 7, the sleeve 93 is provided with an engaging means 95 for engaging the sleeves 93 adjacent in the axial direction so that their axial centers coincide with each other. The engaging means 95 preferably includes an engaging portion 96 in the direction perpendicular to the axis by fitting the shaft portion 96a and the hole portion 96b, and an engaging portion 97 in the axial direction by contacting the surfaces 97a and 97b. . In FIG. 6, the vertical positions of the shaft portion and the hole portion that can be engaged with each other may be reversed.

  Further, a concave portion 98 is provided on the outer surface of the sleeve 93, and a claw portion 99 is provided on the spacer 110 so as to enter and be engaged with the concave portion 98 of the sleeve 93. In the present embodiment, the recess 98 is formed in a ring groove shape on the circumference of the outer surface of the sleeve 93. On the other hand, the claw portion 99 is formed in a ring shape so as to protrude inward from the inner peripheral surface near the tip of the cylindrical portion 110a formed around the hole in which the sleeve 93 of the spacer 110 is disposed. Note that the claw portion 99 is not necessarily formed continuously in the circumferential direction, and may be formed separately at, for example, three locations on the circumference.

  Next, a method for manufacturing the battery module 50 will be described.

  First, as shown in FIG. 5, the tabs 100 t are sandwiched from both sides of the tab 100 t along the direction in which the plurality of batteries 100 are stacked by the electrically insulating spacers 110 having a plate shape in which the sleeves 93 are embedded. The tabs 100t of the adjacent batteries 100 are joined by welding during the stacking operation of the plurality of batteries 100.

  Here, when the tab 100t is sandwiched between the spacers 110, the engaging means 95 provided in the sleeve 93 is engaged, so that the sleeves 93 adjacent in the axial direction are engaged with each other so that their axial centers coincide with each other. To do. By engaging the sleeves 93 arranged in the axial direction in this way, the plurality of spacers 110 are reliably positioned in both the direction perpendicular to the axis and the axial direction of the sleeve 93 and are prevented from being individually displaced.

  In addition, the claw portion 99 of the spacer 110 enters the concave portion 98 of the sleeve 93 and is locked while being elastically deformed. This prevents the sleeves 93 from being separated in the axial direction, thereby preventing the plurality of spacers 110 from being separated.

  A cell unit 60 including a plurality of batteries 100 in which the tab 100 t is sandwiched and stacked by the spacer 110 is disposed in the lower case 71.

  Subsequently, the upper case 72 is covered from above with the cushioning material 94 interposed therebetween, and the edge portion 72a of the upper case 72 is wound around the edge portion 71c of the lower case 71 by caulking. Here, each battery 100 is accommodated in the case 70 so that the power generation element is pressed down. As a result, in the battery 100 including the stacked power generation element, the distance between the electrode plates is kept uniform, and the battery performance is maintained. The central hole of the sleeve 93 of the spacer 110 and the bolt hole 73 formed in the case 70 are positioned by a jig so that the axial centers of both coincide.

  As described above, according to this embodiment, the plurality of batteries 100 can be easily and reliably positioned in the case 70 in a state where the tabs 100t are securely sandwiched between the stacked spacers 110, and the productivity is improved. A good battery module 50 can be provided.

  Next, with reference to FIG. 8, the manufacturing method of the assembled battery 200 comprised from the some battery module 50 is demonstrated.

  First, a plurality of battery modules 50 are stacked on the lower case 201 for assembled batteries. Here, a collar 204 is interposed between the individual battery modules 50.

  The battery module 50 is air-cooled, and a plurality of battery modules 50 are stacked with a space 204 interposed therebetween. The space is used as a cooling air passage through which cooling air for cooling each of the battery modules 50 flows down. By cooling each battery module 50 by flowing cooling air, it is possible to suppress the battery temperature from being lowered and characteristics such as charging efficiency from being lowered.

  Subsequently, the restraint plate 202 is placed on the uppermost battery module 50, and the through bolt 203 is inserted into the bolt hole 73 of the case 70 and the central hole of the sleeve 93, and a plurality of battery modules 50 arranged in a stacked manner. Are clamped and fixed between the lower case 201 and the restraining plate 202. Here, the position of the spacer 110 with respect to the case 70 is finally fixed by inserting the through bolt 203 through the bolt holes 73 of the lower case 71 and the upper case 72 and the sleeve 93 provided in the spacer 110.

  In the battery module 50 of the present embodiment, the sleeves 93 arranged in the axial direction can receive an axial force generated by screw tightening using the through bolts 203. Therefore, it is possible to form the assembled battery 200 in which the plurality of stacked battery modules 50 are fixed with an appropriate and sufficient tightening force.

  FIG. 9 is a diagram corresponding to FIG. 6 of a battery module 50 according to another embodiment. Members common to those in the above embodiment are given the same reference numerals, and descriptions thereof are omitted.

  In the present embodiment, the sleeve 93 provided in the uppermost spacer 110 has an extension portion 93 a that penetrates the bolt hole 73 of the upper case 72 and protrudes outward. In addition, the code | symbol 93b shows the level | step-difference part which the inner surface of the upper case 72 can contact | abut and can be locked.

  According to the present embodiment, the same effects as those of the above-described embodiment can be obtained, and the collars 204 for the extension portions 93a to maintain a predetermined distance between the battery modules 50 stacked in a plurality (see FIG. 8). Therefore, the number of components of the assembled battery 200 can be reduced, and the number of production steps can be reduced.

  The present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the claims.

It is a perspective view which shows the assembled battery comprised by combining the battery module which concerns on one Embodiment of this invention. It is a perspective view which shows the battery module shown by FIG. It is a perspective view which decomposes | disassembles and shows the battery module shown by FIG. It is a perspective view which shows an example of the battery contained in the cell unit main body shown by FIG. It is the schematic diagram which looked at the laminated structure of the spacer which has pinched the tab from the longitudinal direction. It is an expanded sectional view of the A section of FIG. It is an enlarged view of the B section of FIG. It is a fragmentary sectional view of the assembled battery comprised from a some battery module. It is a figure corresponding to FIG. 6 of the battery module which concerns on other embodiment.

Explanation of symbols

50 battery module,
70 cases,
73 bolt holes,
93 Sleeve (hollow member),
93a extension,
95 engagement means,
96 engaging portion perpendicular to the axis,
96a shank,
96b hole,
97 axial engagement,
97a, 97b surface,
98 recess,
99 nails,
100 battery (flat battery),
100a exterior material,
100t tab (electrode terminal),
110 spacer (insulating plate),
200 batteries,
203 through bolts,
204 colors.

Claims (6)

A plurality of flat batteries are formed by sealing a power generation element with an exterior material and leading out plate-like electrode terminals to the outside from the exterior material, and the electrode terminals of each flat battery are electrically connected to each other. A battery module having a case forming an outer frame,
An electrically insulating insulating plate having a plate shape that sandwiches the electrode terminal from both sides of the electrode terminal along a direction in which the plurality of flat batteries are stacked;
A hollow member provided through the insulating plate, the hollow member receiving a tightening axial force when tightened in the axial direction using a shaft member inserted inside, and
The battery module according to claim 1, wherein the hollow member is provided with engagement means for engaging the hollow members adjacent in the axial direction so that the axial centers thereof coincide with each other.   The said engaging means contains the engaging part of the axial orthogonal direction by the fitting of a shaft part and a hole part, and the axial engaging part by contact | abutting of surfaces. The battery module described in 1.   The battery module according to claim 1, wherein the hollow member is configured to be embedded in the insulating plate when the insulating plate is formed. The outer surface of the hollow member is provided with a recess,
The battery module according to any one of claims 1 to 3, wherein the insulating plate is provided with a claw portion that enters and is locked into the concave portion of the hollow member.   5. The battery module according to claim 1, wherein the hollow member provided in the uppermost insulating plate has an extension portion that penetrates the case and protrudes outward. 6. A plurality of flat batteries are formed by sealing a power generation element with an exterior material and leading out plate-like electrode terminals to the outside from the exterior material, and the electrode terminals of each flat battery are electrically connected to each other. A battery module manufacturing method comprising:
A hollow member that receives a tightening axial force when being tightened in the axial direction by using a shaft member inserted into the electrode terminal from both sides of the electrode terminal along the direction in which the plurality of flat batteries are stacked is embedded. Sandwiching it with a plate-like electrically insulating insulating plate; and
Arranging a plurality of flat batteries in which each electrode terminal is sandwiched and laminated by the insulating plate in a case, and
In the clamping step, the engagement means provided in the hollow member are engaged, so that the hollow members adjacent in the axial direction are engaged with each other so that their axial centers coincide with each other. Module manufacturing method.

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