JP2017004923A - Method for manufacturing battery module and locking jig - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of manufacturing a battery module and a constraining jig capable of suppressing an increase in working man-hours.SOLUTION: A method of manufacturing a battery module including an array body 10 in which a plurality of battery cells 2 are arranged, an elastic member 4 disposed on at least one side in an arrangement direction D with respect to the array body 10, a pair of brackets 6 sandwiching the array body 10 and the elastic member 4, a restraining member for restraining the array body 10 and the elastic member 4 sandwiched between the pair of brackets 6 comprises a load adding step of adding a load to the array body 10 and the elastic member 4 sandwiched between the pair of brackets 6 for a predetermined period, and a restraining step of restraining the array body 10 and the elastic member 4 sandwiched between the pair of brackets 6 by the restraining member after the end of the load adding step. The load adding step may be performed during the self-discharging step of self-discharging the battery cell 2 of the battery module.SELECTED DRAWING: Figure 5

Description

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

  As a conventional battery module, for example, a battery module described in Patent Document 1 is known. The battery module described in Patent Document 1 includes a stacked body in which battery cells held by a battery holder are stacked, a pair of end plates disposed on both sides of the stacked body, and the stacked body and the end plate. The elastic member is disposed, and a laminated body sandwiched between a pair of end plates and a restraining member that restrains the elastic member. A load is applied to the laminate and the elastic member constrained by the constraining member.

JP 2009-81056 A

  The battery module manufacturing process includes a self-discharge process in order to check the quality of the battery module. In the self-discharge process, the battery module is left for a predetermined period (for example, several days) to self-discharge the battery cell. In this self-discharge step, a load is applied to the elastic member constrained by the constraining member for a predetermined period, so the elastic member may creep. When the elastic member creeps (when the elastic member contracts in the thickness direction), the restraint member is not properly restrained, and, for example, floating occurs between the restraint member and the end plate. In this case, it is necessary to rework the restraining member, and the number of work steps increases.

  Accordingly, an object of the present invention is to propose a battery module manufacturing method capable of suppressing an increase in the number of work steps and a restraining jig used therefor.

  A battery module manufacturing method according to one aspect of the present invention includes an array in which a plurality of battery cells are arrayed, an elastic member disposed on at least one side in the array direction with respect to the array, and the array and the elastic member. A battery module manufacturing method comprising a pair of end plates sandwiching a pair, and an array body sandwiched between the pair of end plates and a restraining member that restrains the elastic member, the array body sandwiched between the pair of end plates and the elasticity A load applying step of applying a load to the member for a predetermined period, and a restraining step of restraining the array body and the elastic member sandwiched between the pair of end plates by the restraining member after the end of the load adding step.

  In this manufacturing method, the elastic member is creeped before being restrained by the restraining member by applying a load to the elastic member for a predetermined period before being restrained by the restraining member. And in this manufacturing method, since the elastic member after creeping is restrained by the restraining member, it is not necessary to perform a reworking work on the restraining member, and an increase in the number of work steps can be suppressed.

  In the battery module manufacturing method of one embodiment, the load applying step may be performed during a self-discharge step of self-discharging the battery cells of the battery module. In this manufacturing method, the load adding step is carried out by effectively utilizing the self-discharge step required for a predetermined period.

  The restraining jig according to one aspect of the present invention includes an array in which a plurality of battery cells are arrayed, an elastic member disposed on at least one side in the array direction with respect to the array, the array, and the elasticity. A restraining jig for restraining an unconstrained battery module comprising a pair of end plates sandwiching a member, wherein a body part on which the unconstrained battery module is placed, and an unconstrained battery module placed on the body part A pair of load applying portions arranged so as to be sandwiched in the arrangement direction of the battery cells, and the main body portion has the other load addition to the one load addition portion at a pitch corresponding to the thickness of the battery cells in the arrangement direction. An interval adjusting unit is provided that makes the interval between the portions variable.

  In this restraining jig, an interval adjusting unit is provided that makes the interval of the other load applying portion variable with respect to one load applying portion at a pitch corresponding to the thickness in the arrangement direction of the battery cells. Therefore, when restraint is performed on unconstrained battery modules having different numbers of battery cells, it is not necessary to prepare restraining jigs having different dimensions and shapes, and the load adding step can be easily performed.

  In addition, the battery module manufacturing method according to one aspect of the present invention includes an array in which a plurality of battery cells are arrayed, an elastic member disposed on at least one side in the array direction with respect to the array, an array, and A battery module manufacturing method comprising a pair of end plates sandwiching an elastic member, an array body sandwiched between the pair of end plates, and a restraining member restraining the elastic member, the array being sandwiched between the pair of end plates A load applying step of applying a load to the body and the elastic member for a predetermined period, and a restraining step of restraining the arrayed body and the elastic member sandwiched between the pair of end plates by the restraining member after the end of the load adding step, The load adding step includes the step of placing the unconstrained battery module on the main body of the restraining jig and the number of battery cells arranged in the unconstrained battery module by the interval adjusting unit. In response, and a step of adjusting the spacing of the other load application portion against one of the load application part.

  In this manufacturing method, in the load applying step, a restraint jig provided with a distance adjusting portion that can vary the distance between one load applying portion and the other load adding portion at a pitch corresponding to the thickness in the arrangement direction of the battery cells. Is used. This eliminates the need to prepare restraining jigs having different dimensions and shapes when restraining unconstrained battery modules having different arrangement numbers of battery cells, so that the load applying process can be easily performed.

  In the battery module manufacturing method of one embodiment, the load applying step may be performed during a self-discharge step of self-discharging the battery cells of the battery module. In this manufacturing method, the load adding step is carried out by effectively utilizing the self-discharge step required for a predetermined period.

  According to the present invention, an increase in work man-hours can be suppressed.

It is a top view of the battery module which concerns on one Embodiment. It is a perspective view of the pallet for self-discharge used at a self-discharge process. It is a perspective view which shows the state (before load addition) in which the unconstrained battery module was mounted in the pallet for self-discharge. It is a perspective view which shows the state (during load addition) in which the unconstrained battery module was accommodated in the pallet for self-discharge. It is sectional drawing which shows the state (during load addition) in which the unconstrained battery module was accommodated in the pallet for self-discharge. It is a perspective view which shows the modification of the pallet for self-discharge.

  Hereinafter, with reference to drawings, the manufacturing method of the battery module concerning the embodiment of the present invention is explained. In addition, the same code | symbol is attached | subjected about the element which is the same or it corresponds in each figure, and the overlapping description is abbreviate | omitted.

  Before explaining the manufacturing method of the battery module 1, the battery module 1 is demonstrated with reference to FIG. FIG. 1 is a plan view of a battery module 1 according to an embodiment. The battery module 1 may be used, for example, as a single battery module 1 or as a battery pack in which a plurality of battery modules 1 are housed in a housing.

  The battery module 1 includes a plurality of battery cells 2, a plurality of battery holders 3, an elastic member 4, a middle plate 5, a pair of brackets 6, a plurality of restraining bolts 7, a plurality of nuts 8, and a cover 9. And. The plurality of battery cells 2 are arranged along one direction (arrangement direction D) while being held by the battery holder 3, thereby forming an array 10. The elastic member 4 and the middle plate 5 are disposed on one side of the array body 10 in the array direction D. The pair of brackets 6 are disposed on both sides in the arrangement direction D. The plurality of restraint bolts 7 and nuts 8 restrain the array body 10, the elastic member 4, and the middle plate 5 sandwiched between the pair of brackets 6.

  The battery cell 2 is, for example, a storage battery such as a non-aqueous electrolyte secondary battery such as a lithium ion secondary battery, or an electric double layer capacitor. The battery cell 2 accommodates an electrolytic solution and an electrode assembly in a box-shaped case. The electrode assembly has a plurality of separators that insulate the positive electrode, the negative electrode, and the positive electrode and the negative electrode. The plurality of positive electrodes, the negative electrode, and the separator are stacked with the separator sandwiched between the positive electrode and the negative electrode. The battery cell 2 has a positive electrode terminal (not shown) and a negative electrode terminal (not shown). The plurality of battery cells 2 are arranged so that positive and negative terminals having different polarities are adjacent to each other. The plurality of battery cells 2 are electrically connected in series by a bus bar (not shown). Adjacent battery cells 2 are in close contact via a heat transfer plate (not shown). In this embodiment, as shown in FIG. 1 and the like, the number of battery cells 2 is seven.

  The battery holder 3 is a member that holds the battery cell 2. As shown in FIG. 3, the battery holder 3 is a substantially U-shaped frame body as viewed from the arrangement direction D. The battery holder 3 has a first side portion 3a that forms one end of the U-shape and a first side that forms the other end. 2 side part 3b, and the 1st side part 3a and the 2nd side part 2b are connected, and it has the main-body part (not shown) accommodated so that the battery cell 2 may be surrounded. The battery holder 3 is made of, for example, resin. The battery holder 3 is formed with a through hole (not shown) penetrating in the arrangement direction D. Restraint bolts 7 are inserted through the through holes. The number of through holes is the same as the number of restraint bolts 7.

  The elastic member 4 is a member that absorbs expansion in the arrangement direction D of the battery cells 2. The elastic member 4 is made of an elastic material. The elastic member 4 is formed in a flat plate shape by rubber, for example. The elastic member 4 is disposed between the middle plate 5 and the bracket 6 that are disposed at one end of the array body 10 in the array direction D. The planar shape viewed from the arrangement direction D of the elastic members 4 is, for example, a substantially rectangular shape and is smaller than the outer shape of the middle plate 5. For example, the elastic member 4 may be assembled to the middle plate 5 by engagement means (not shown), and may be positioned with respect to the array body 10 in a direction orthogonal to the array direction D. The battery module 1 may include the elastic members 4 on both sides of the array body 10 in the array direction D.

  The middle plate 5 is a member for suppressing variations in load applied from the elastic member 4 to the plurality of battery cells 2 (array 10). The middle plate 5 is formed in a flat plate shape by a metal material, for example. The middle plate 5 is disposed between the array body 10 and the elastic member 4. The planar shape seen from the arrangement direction D of the middle plate 5 is, for example, a substantially rectangular shape and larger than the outer shape of the elastic member 4. A through hole 5 a is formed in the middle plate 5. Restraint bolts 7 are inserted through the through holes 5a. The number of through holes 5a is the same as the number of restraint bolts 7. The battery module 1 may not include the middle plate 5.

  The pair of brackets 6 are members for restraining the array body 10, the elastic member 4, and the middle plate 5 to apply a load and fixing the battery module 1 at a predetermined location. The bracket 6 includes a sandwiching portion 6a, a fixing portion 6b, and a plurality of rib portions 6c. The sandwiching portion 6a is a portion that sandwiches the array body 10, the elastic member 4, and the middle plate 5, and functions as an end plate. The clamping part 6a is a substantially rectangular flat plate shape. A through hole 6d is formed in the clamping portion 6a. Restraint bolts 7 are inserted into the through holes 6d. The number of through holes 6d is the same as the number of restraining bolts 7. The fixing | fixed part 6b is a part fixed to the predetermined location of the side wall of the housing | casing of a battery pack, for example. The fixing portion 6b is a flat plate erected on one end portion of the clamping portion 6a. A through hole 6e is formed in the fixed portion 6b. In this embodiment, as shown in FIG. 1 and the like, the number of through holes 6e is four. A bolt (not shown) for fixing to a predetermined location is inserted into the through hole 6e. The rib portion 6c is a member that reinforces the sandwiching portion 6a and the fixing portion 6b. As shown in FIG. 3, the rib portion 6 c has a substantially triangular flat plate shape projecting to one surface side of the sandwiching portion 6 a and the fixing portion 6 b. The plurality of rib portions 6c are arranged at a predetermined interval. In this embodiment, the number of rib portions 6c is three.

  The restraint bolt 7 and the nut 8 are restraint members that restrain the array body 10, the elastic member 4, and the middle plate 5 sandwiched between the pair of brackets 6. The restraint bolt 7 is a long bolt that is longer than between the sandwiching portions 6 a of the pair of brackets 6. The number of the restraint bolts 7 is four, for example. The plurality of restraint bolts 7 extend in the arrangement direction D and connect the pair of brackets 6 to each other. The plurality of restraining bolts 7 are inserted through the through holes 6 d of the pair of brackets 6, the through holes 5 a of the middle plate 5, and the through holes of the battery holder 3, respectively. The plurality of restraining bolts 7 are respectively screwed into the nuts 8 on the outer side of the sandwiching portion 6a of the bracket 6. By restraint using the plurality of restraint bolts 7 and nuts 8, a restraint load is applied to the plurality of battery cells 2 and the elastic member 4. A double nut may be used to prevent the nut 8 from loosening.

  The cover 9 is a member that closes the upper end openings of the plurality of battery holders 3 arranged along the arrangement direction D and mounts a control unit or the like (not shown) of the battery module 1. The cover 9 is arrange | positioned between the 1st side part 3a and the 2nd side part 3b of the some battery holder 3 arranged as shown in FIG.

  A method for manufacturing the battery module 1 having the above configuration will be described. In this embodiment, a load adding process, a self-discharge process, and a restraining process in the manufacturing method will be described in detail. For other manufacturing processes, conventional manufacturing processes are applied. Before describing each process, the self-discharge pallet (restraint jig) 20 used in the self-discharge process and the load application process will be described with reference to FIG. FIG. 2 is a perspective view of the self-discharge pallet 20. In the self-discharge process and the load application process, the battery module 1 that is not yet restrained by the restraining members (the restraining bolt 7 and the nut 8) (hereinafter, the battery module 1 in this state is referred to as the unconstrained battery module 1 ′). Implemented).

  The self-discharge pallet 20 is a pallet used for a self-discharge process and conveyance between the processes before and after the self-discharge process. The self-discharge pallet 20 has a function of applying a load to the unconstrained battery module 1 ′ (particularly, the array 10 and the elastic member 4 sandwiched between the sandwiching portions 6a of the pair of brackets 6). It is.

  The self-discharge pallet 20 is sized to accommodate a part of the unconstrained battery module 1 ′ (the portion sandwiched between the sandwiching portions 6a of the pair of brackets 6 as shown in FIG. 5). Is a box with an opening. The self-discharge pallet 20 is made of, for example, a metal material. The self-discharge pallet 20 includes a bottom plate portion 21, side wall portions 22 and 23, and load applying portions 24 and 25. The bottom plate portion 21 is a rectangular flat plate having a predetermined thickness. The side wall portions 22 and 23 are arranged to face each other and are erected on each edge portion of the bottom plate portion 21. The side walls 22 and 23 are rectangular flat plates having a predetermined thickness. When the unconstrained battery module 1 ′ is accommodated in the self-discharge pallet 20, as shown in FIG. 4, the side wall portion 22 is a portion that follows the first side portion 3 a of the battery holder 3, and the side wall portion 23 is a battery. This is a portion that follows the second side 3 b of the holder 3. The load applying portion 24 is erected on the edge portion of the bottom plate portion 21 and is fixed to one side edge portion of the side wall portion 22 and one side edge portion of the side wall portion 23. The load application portion 25 functions as a door that opens and closes an opening formed by the edge portion of the bottom plate portion 21 and the other side edge portion of the side wall portions 22 and 23, and is freely rotatable on the other side edge portion of the side wall portion 23. It is attached. When the load application part 25 closes the opening, the load application part 24 and the load application part 25 face each other.

  When the unconstrained battery module 1 ′ is accommodated in the self-discharge pallet 20, the load applying portions 24 and 25 apply a load to the unconstrained battery module 1 ′. The load applying portions 24 and 25 are composed of flat plate portions 24a and 25a and a plurality of contact portions 24b and 25b. The flat plate portions 24a and 25a are rectangular flat plates having a predetermined thickness. A flat plate portion 24 a of the load applying portion 24 is erected on the edge portion of the bottom plate portion 21 and is fixed to each side edge portion of the side wall portions 22 and 23. The flat plate portion 25 a of the load adding portion 25 is rotatably attached to the side edge portion of the side wall portion 23. The contact portions 24b and 25b have a substantially rectangular parallelepiped shape. As shown in FIG. 5, the abutting portions 24 b and 25 b abut on the outer surface of the clamping portion 6 a of the bracket 6 when the self-discharge pallet 20 is accommodated in the unconstrained battery module 1 ′. The plurality of contact portions 24b and 25b are fixed to the flat plate portions 24a and 25a at predetermined intervals so as not to contact the plurality of rib portions 6c of the bracket 6. The number of the contact portions 24 b and 25 b is one more than the number of the rib portions 6 c of the bracket 6. In this embodiment, since the rib part 6c is three, the contact parts 24b and 25b are four.

  The load adding portion 25 is fixed to the other side edge portion of the side wall portion 22 in a state where the above-described opening portion is closed. As this fixing method, as shown in FIG. 4, bolt fastening using a bolt 26 may be mentioned. Therefore, a plurality of through holes 25c are formed at the end of the flat plate portion 25a. Bolts 26 are inserted through these through holes 25c. A plurality of bolt holes 22b having screw grooves are formed on the end surface 22a of the side wall portion 22 so as to face the positions of the plurality of through holes 25c of the flat plate portion 25a. Bolts 26 are screwed into these bolt holes 22b. In this embodiment, the number of through holes 25c and bolt holes 22b is five. In addition, as this fixing method, fixing methods other than bolt fastening may be sufficient, for example, the fixing method using a hook is mentioned.

  When the unconstrained battery module 1 ′ is accommodated in the self-discharge pallet 20 and the load applying portion 24 is fixed to the side wall portion 22 by bolt fastening, as shown in FIG. 24 b abuts on the clamping portion 6 a of one bracket 6, and a plurality of abutting portions 25 b of the load applying portion 25 abuts on the clamping portion 6 a of the other bracket 6. Thereby, a load is applied to the unconstrained battery module 1 ′ (in particular, the plurality of battery cells 2 and the elastic member 4 of the array 10). The load applied to the unconstrained battery module 1 ′ is preferably a load equivalent to or higher than the load applied to the battery module 1 by the restraining members (restraint bolts 7 and nuts 8). For example, 10-20 kN.

  A method for manufacturing the battery module 1 will now be described with reference to FIGS. 3 to 5 in addition to FIGS. FIG. 3 is a perspective view showing a state where the unconstrained battery module 1 ′ is placed on the self-discharge pallet 20 (before applying a load). FIG. 4 is a perspective view showing a state where the unconstrained battery module 1 ′ is accommodated in the self-discharge pallet 20 (during application of a load). FIG. 5 is a cross-sectional view showing a state where the unconstrained battery module 1 ′ is accommodated in the self-discharge pallet 20 (during application of a load).

  First, a plurality of battery cells 2 are respectively stored in the battery holder 3 and arranged along the arrangement direction D by the same manufacturing process as in the prior art. Thereby, the array body 10 is obtained. The middle plate 5 is disposed on one end side in the arrangement direction D of the array body 10. The elastic member 4 is disposed outside the middle plate 5. Furthermore, one bracket 6 is disposed at one end portion in the arrangement direction D, and the other bracket 6 is disposed at the other end portion. In addition, the cover 9 is disposed between the first side portion 3 a and the second side portion 3 b of the plurality of battery holders 3 of the array 10. Thereby, the unconstrained battery module 1 'is obtained. As shown in FIG. 3, the unconstrained battery module 1 ′ is placed on the bottom plate portion 21 of the self-discharge pallet 20. In addition, you may place in the pallet 20 for self-discharge in the state which became unconstrained battery module 1 ', or one part assembly process before becoming unconstrained battery module 1' may be carried out. 20 may be performed.

  The load adding process will be described. As shown in FIG. 4, the load applying portion 25 is closed in a state where the unconstrained battery module 1 ′ is placed on the bottom plate portion 21 of the self-discharge pallet 20. A plurality of bolts 26 are inserted into the through holes 25 c of the load application portion 25 and screwed into the bolt holes 22 b of the side wall portion 22. Thereby, the load addition part 25 is fixed to the side wall part 22, and a part of the unconstrained battery module 1 'is accommodated in the pallet 20 for self-discharge.

  As shown in FIG. 5, the plurality of abutting portions 25b of the load applying portion 25 abut on the outer surface of the clamping portion 6a of one bracket 6 on the side where the elastic member 4 is disposed, and are applied to the other bracket 6 side. Press. Further, the plurality of contact portions 24 b of the load applying portion 24 abut on the outer surface of the clamping portion 6 a of the other bracket 6 and pressurize the one bracket 6 side. As a result, a predetermined amount of load is applied to the array body 10 and the elastic member 4 sandwiched between the pair of brackets 6 from both sides in the array direction D. This load adding step is performed at least during the self-discharge step.

  The self-discharge process will be described. The unconstrained battery module 1 ′ is stored in a predetermined place prepared for self-discharge for a predetermined period in a state of being accommodated in the self-discharge pallet 20. This predetermined period is, for example, 2 to 5 days. During the self-discharge process, the battery cell 2 self-discharges with a load applied from both sides in the arrangement direction D. Note that the self-discharge process is performed in order to check the quality of the battery module 1 (particularly, the battery cell 2). In the quality confirmation, for example, whether or not the battery cell 2 is internally short-circuited is determined based on a voltage difference before and after the self-discharge process of the battery cell 2 or a current flowing through the battery cell 2 during the self-discharge process.

  During the self-discharge process (during the load applying process), the elastic member 4 is compressed and deformed in the arrangement direction D by applying a load from the holding part 6a of the bracket 6, and also has a reaction force against the holding part 6a. Is generated. During the predetermined period of the self-discharge process, a load continues to be applied to the elastic member 4. For this reason, the elastic member 4 creeps as the strain in the arrangement direction D increases with time. As a result, the elastic member 4 shrinks by a predetermined amount in the arrangement direction D (thickness decreases by a predetermined amount), and the shrinkage remains even after the load is removed. Thereby, the reaction force with respect to the clamping part 6a of the elastic member 4 also becomes small.

  The restraining process will be described. When the self-discharge process is completed, the plurality of bolts 26 are removed from the bolt holes 22 b of the side wall portion 22 and are removed from the through holes 25 c of the load applying portion 25. And the load addition part 25 is opened and the one end side of the pallet 20 for self-discharge is opened. Thereby, a load addition process is complete | finished. The unconstrained battery module 1 ′ is taken out from the self-discharge pallet 20. Then, a plurality of restraining bolts 7 pass through the through-hole 6d of one bracket 6 of the unconstrained battery module 1 ', the through-hole 5a of the middle plate 5, the through-holes of the arranged battery holders 3, and the through-hole of the other bracket 6. The holes 6d are inserted into the nuts 8 and screwed into the nuts 8, respectively. As a result, the array body 10, the elastic member 4, and the middle plate 5 sandwiched between the pair of brackets 6 by the plurality of restraint bolts 7 and nuts 8 are restrained to form the battery module 1. In the battery module 1, a predetermined amount of load is applied to the array body 10 and the elastic member 4 sandwiched between the pair of brackets 6 from both sides in the array direction D.

  As a method of adjusting the thickness of the elastic member 4 that is elastically deformed, for example, a thickness adjusting jig having a predetermined thickness at a location where the elastic member 4 is not disposed between the clamping portion 6a of the bracket 6 and the middle plate 5 is used. In a state where the tool is sandwiched, the restraint bolt 7 and the nut 8 are tightened so that the thickness adjusting jig is sandwiched between the sandwiching portion 6a and the middle plate 5, and after the tightening, one of the restraint bolt 7 and the nut 8 is replaced with the other. For example, a method of rotating a certain number of times in the loosening direction and taking out the thickness adjusting jig in that state can be mentioned.

  As described above, the elastic member 4 has already been creeped by the load applying process before the restraining process. Therefore, after being restrained by the restraining bolt 7 and the nut 8 in the restraining step, the elastic member 4 hardly creeps even if a load continues to be applied. Further, since the restraint bolt 7 and the nut 8 are tightened in the restraint process after the self-discharge process is finished, the elastic member 4 creeps and floats between the restraint bolt 7 and the clamping portion 6a of the bracket 6 after the restraint process. Will not occur. Therefore, there is no need to rework the tightening of the restraint bolt 7 and the nut 8 after the restraint process.

  In this method of manufacturing the battery module 1, the elastic member 4 is creeped before being restrained by applying a load to the elastic member 4 for a predetermined period before being restrained by the restraining bolt 7 and the nut 8. Can do. In this manufacturing method, the elastic member 4 after creeping is restrained by the restraining bolt 7 and the nut 8, so that it is not necessary to rework the fastening of the restraining bolt 7 and the nut 8 after the restraining process, and the number of work steps is increased. Can be suppressed. Accordingly, the battery module manufactured by this manufacturing method has a high yield rate. Moreover, in this manufacturing method, the load adding process can be carried out by effectively utilizing the self-discharge process required for a predetermined period.

  As mentioned above, although embodiment of this invention was described, it is implemented in various forms, without being limited to the said embodiment.

  For example, in the above-described embodiment, the load application process is performed in the self-discharge process, but the load application process may be performed in another process such as an aging process.

  In the above embodiment, the load is applied in the load adding process using a self-discharge pallet incorporating a load adding function. However, the load is applied by using a load applying device separate from the self-discharge pallet. It is good also as a structure which adds. In this case, the same self-discharge pallet is used.

  In the present embodiment, since the battery module is fixed to the wall portion of the battery pack housing or the like, a bracket that also functions as an end plate is used. However, when it is not necessary to fix the battery module, the end plate is used. A flat plate may be used, and even when it is necessary to fix the bracket, the bracket may be formed separately from the flat end plate.

  Further, in the present embodiment, the restraint member is constituted by a restraint bolt (screw member) and a nut, but the restraint member may be another member such as a restraint band.

  FIG. 6 is a perspective view showing a modification of the self-discharge pallet. The self-discharge pallet (restraint jig) 30 shown in FIG. 2 is provided with an interval adjusting unit 31 that adjusts the interval between the load applying unit 24 and the load adding unit 25. This is different from the pallet 20 for use.

  More specifically, in the self-discharge pallet 30, the length in the longitudinal direction of the bottom plate portion 21 and the side wall portions 22 and 23 (here, the direction in which the load applying portion 24 and the load adding portion 25 face each other) is the self-discharge pallet. 20 is longer than the length of the bottom plate 21 and the side walls 22, 23. In addition, the load applying portion 24 is not fixed to the bottom plate portion 21 and is provided as a separate body, and a flat plate portion 24a of the load adding portion 24 can be detachably attached to the side wall portions 22 and 23 as an interval adjusting portion 31 from above. A plurality of notches 32 that can be inserted are provided.

  In the form shown in FIG. 6, five notches 32 are provided in the longitudinal direction of the side walls 22, 23 at a pitch corresponding to the thickness in the arrangement direction D of the battery cells 2. In this embodiment, since the battery cell 2 is held by the battery holder 3, the pitch P of the notches 32 substantially matches the widths of the first side 3 a and the second side 3 b in the battery holder 3. By selecting the notch portion 32 into which the load adding portion 24 is inserted, the interval of the load adding portion 24 with respect to the load adding portion 25 in the state where the opening is closed is variable, and the interval is not changed according to the number of the battery cells 2 arranged. It can be matched to the length in the arrangement direction D of the constrained battery module 1 ′.

  The self-discharge pallet 30 is provided with five notches 32 in the longitudinal direction of the side walls 22 and 23, and can accommodate 5 to 9 unconstrained battery modules 1 'in which the number of battery cells 2 is arranged. It has become. The number of notches 32 formed is appropriately changed according to the specifications of the battery module 1 to be manufactured (the number of battery cells 2 arranged).

  When the self-discharge pallet 30 is used, the unconstrained battery module 1 ′ is placed on the bottom plate portion 21 of the self-discharge pallet 30 in the load adding step. Next, the load applying part 24 is inserted into the notch 32 selected according to the number of the battery cells 2 arranged in the unconstrained battery module 1 ′, and the distance between the load adding part 24 and the load adding part 25 in the state where the opening is closed. Adjust. Thereafter, the opening is closed by the load application portion 25, and the array direction with respect to the array body 10 and the elastic member 4 sandwiched between the pair of brackets 6 at least during the self-discharge process as in the above-described embodiment. Load is applied from both sides of D. Note that the load applying portion 24 may be inserted into the notch 32 in advance before placing the unconstrained battery module 1 ′ on the bottom plate portion 21 of the self-discharge pallet 30.

  In such a manufacturing method of the battery module 1, by using the self-discharge pallet 30, when restraint is performed on the unconstrained battery module 1 ′ in which the number of battery cells 2 is different, the restraint treatment having different dimensions and shapes is performed. It is not necessary to prepare each tool, and the load adding step can be easily performed. Moreover, in this manufacturing method, the load adding process can be carried out by effectively utilizing the self-discharge process required for a predetermined period.

  DESCRIPTION OF SYMBOLS 1 ... Battery module, 1 '... Unrestrained battery module, 2 ... Battery cell, 4 ... Elastic member, 6a ... Holding part (end plate), 7 ... Restraint bolt (restraint member), 8 ... Nut (restraint member), 10 ... array, 20, 30 ... self-discharge pallet (restraint jig), 21 ... bottom plate part (main part), 22, 23 ... side wall part (main part), 24, 25 ... load applying part, 31 ... spacing adjustment Department.

Claims (5)

An array in which a plurality of battery cells are arrayed, an elastic member disposed on at least one side in the array direction with respect to the array, a pair of end plates sandwiching the array and the elastic member, and the pair of A battery module manufacturing method comprising: the arrayed body sandwiched between end plates; and a restraining member that restrains the elastic member,
A load applying step of applying a load to the array and the elastic member sandwiched between the pair of end plates for a predetermined period;
A restraining step of restraining the array member and the elastic member sandwiched between the pair of end plates after the end of the load applying step by the restraining member;
A method for manufacturing a battery module, comprising:   The battery module manufacturing method according to claim 1, wherein the load adding step is performed during a self-discharge step of self-discharging the battery cells of the battery module. An array including a plurality of battery cells, an elastic member disposed on at least one side in the array direction with respect to the array, and a pair of end plates sandwiching the array and the elastic member A restraining jig for restraining the restraining battery module,
A main body on which the unconstrained battery module is placed;
A pair of load applying portions disposed so as to sandwich the unconstrained battery module placed on the main body portion in the arrangement direction of the battery cells,
The restraint jig in which the said main-body part is provided with the space | interval adjustment part which makes variable the space | interval of the other load addition part with respect to one load addition part with the pitch corresponding to the thickness of the said arrangement direction in the said battery cell. An array in which a plurality of battery cells are arrayed, an elastic member disposed on at least one side in the array direction with respect to the array, a pair of end plates sandwiching the array and the elastic member, and the pair of A battery module manufacturing method comprising: the arrayed body sandwiched between end plates; and a restraining member that restrains the elastic member,
A load applying step of applying a load to the array and the elastic member sandwiched between the pair of end plates for a predetermined period;
A restraint step of restraining the array member and the elastic member sandwiched between the pair of end plates after the end of the load applying step by the restraint member,
The load applying step includes
Placing the unconstrained battery module on the main body of the restraining jig according to claim 3;
Adjusting the interval of the other load applying portion with respect to the one load applying portion in accordance with the number of the battery cells arranged in the unconstrained battery module by the interval adjusting portion. Method.   The said load addition process is a manufacturing method of the battery module of Claim 4 implemented during the self-discharge process which self-discharges the said battery cell of the said battery module.

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