JP2019053898A - Manufacturing method of battery pack - Google Patents

Abstract

To provide a manufacturing method of battery pack capable of restraining curvature of a sheet-like member, constituting an electrode, at the time of lamination, while restraining misalignment of electrode.SOLUTION: A (i+1)th electrode member is laminated on an i-th electrode member fixed by means of a first clamp (step S40). Here, the tub of the (i+1)th electrode member has a part overlapping with the tub of the i-th electrode member, and is offset by a specified quantity in the plane direction for the tub of the i-th electrode member so as not to interfere with the first clamp fixing the tub of the i-th electrode member. When the (i+1)th electrode member is laminated, the tub of the (i+1)th electrode member is fixed by a second clamp at the overlapping part of the tub of the (i+1)th electrode member and the tub of the i-th electrode member (step S70).SELECTED DRAWING: Figure 11

Description

  The present disclosure relates to a method for manufacturing an assembled battery, and more particularly, to a method for manufacturing an assembled battery for stacking a plurality of sheet-like members each constituting an electrode to form the assembled battery.

  An assembled battery used as a driving power source for a vehicle driving motor or the like is required to have a large capacity in order to secure a cruising distance. As such a large-capacity assembled battery, an assembled battery configured by laminating a plurality of sheet-like members each constituting an electrode is known.

  Regarding such a method for manufacturing a laminated battery pack, for example, in Japanese Patent Application Laid-Open No. 2012-221715 (Patent Document 1), when a sheet member including at least one of an electrode and a separator is laminated, the laminated battery is laminated so far. In order to suppress the displacement of the sheet member, a lamination method is disclosed in which the sheet member is sequentially laminated while the laminate is fixed by a clamp (see Patent Document 1).

JP2012-221715A JP 2014-11040 A JP 2009-277673 A

  In the lamination method described in Patent Document 1, when a sheet member is laminated on a laminated body fixed by a clamp, the laminated sheet member interferes with the clamp. As a result, the sheet member is bent and the adhesion between the electrodes is lowered. As a result, the resistance of the battery is increased and the battery performance may be lowered.

  The present disclosure has been made in order to solve such a problem, and an object of the present disclosure is to provide an assembled battery capable of suppressing bending of a sheet-like member constituting an electrode at the time of lamination while suppressing displacement of the electrode laminate. It is to provide a manufacturing method.

  The method for manufacturing an assembled battery according to the present disclosure is a manufacturing method for forming an assembled battery by stacking a plurality of sheet-like members each constituting an electrode. Each sheet-like member includes a tab protruding from a part of one side of the sheet-like member. The manufacturing method includes a step of laminating the first sheet-like member, a step of fixing the first tab that is a tab of the first sheet-like member with the first clamp, and the first tab being the first tab. And laminating a second sheet-like member on top of the first sheet-like member while being fixed with one clamp. Here, the 2nd tab which is a tab of the 2nd sheet-like member has an overlap part with the 1st tab, and it does not interfere with the 1st clamp which has fixed the 1st tab. It is offset in the planar direction with respect to the first tab. The manufacturing method further includes a step of fixing the second tab with the second clamp at the overlapping portion.

  In the assembled battery manufacturing method of the present disclosure, the second tab of the second sheet-like member stacked on the upper portion of the first sheet-like member is the first tab so as not to interfere with the first clamp. Since the second tab is offset, the second sheet-like member can be laminated on the upper portion of the first sheet-like member without the second tab interfering with the first clamp. Therefore, according to the manufacturing method of the assembled battery of this indication, it can control that the sheet-like member which constitutes an electrode bends at the time of lamination, suppressing shift of an electrode layered product. As a result, it can suppress that battery performance falls by the adhesive fall of electrodes.

It is the perspective view which showed the external appearance of the electrode body of the assembled battery manufactured by the manufacturing method of the assembled battery according to embodiment of this indication. It is a figure explaining a part of manufacturing process of each electrode member. It is the figure which showed typically the cross section along III-III in FIG. It is sectional drawing of the rotary cutting blade for cutting an electrode member with a product width. It is sectional drawing of the rotary type tab cutting blade for forming a tab in an electrode member. It is the figure which showed the arrangement | positioning relationship of a tab when an electrode member is laminated | stacked. It is the 1st figure which showed arrangement | positioning of each tab at the time of an electrode member being laminated | stacked, and the operation | movement of a clamp. It is the 2nd figure which showed arrangement | positioning of each tab at the time of an electrode member being laminated | stacked, and the operation | movement of a clamp. It is the 3rd figure which showed arrangement | positioning of each tab at the time of an electrode member being laminated | stacked, and the operation | movement of a clamp. It is the 4th figure which showed arrangement | positioning of each tab at the time of an electrode member being laminated | stacked, and the operation | movement of a clamp. It is a flowchart explaining the procedure of the manufacturing method of the assembled battery according to this Embodiment. It is sectional drawing of the positive electrode sheet and negative electrode sheet which are laminated | stacked alternately.

  Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. In the drawings, the same or corresponding portions are denoted by the same reference numerals and description thereof will not be repeated.

  FIG. 1 is a perspective view showing an appearance of an electrode body of an assembled battery manufactured by the method for manufacturing an assembled battery according to the embodiment of the present disclosure. Referring to FIG. 1, an electrode body 10 is configured by laminating a plurality of sheet-like electrode members each constituting an electrode. Each electrode member is formed in a sheet-like rectangle and includes a tab 12 protruding from a part of one side (width A) of the electrode member. Each electrode member is laminated so that the tab 12 protrudes in the same direction in the electrode body 10.

  The tab 12 of each electrode member is formed so as to have an offset while having an overlapping portion in the plane direction with respect to the tab 12 of the electrode member immediately below at the time of lamination. As a result, as shown in the drawing, the plurality of tabs 12 protruding from the electrode body 10 are provided stepwise with respect to the stacking direction of the electrode members. Thereby, when each electrode member is laminated | stacked and the electrode body 10 is comprised, the clamp for fixing the laminated body laminated | stacked until then, and the tab 12 of the electrode member further laminated | stacked on a laminated body are provided. The electrode members can be stacked without interference. Hereinafter, a method for manufacturing the assembled battery according to the present embodiment will be described in detail.

  FIG. 2 is a diagram for explaining a part of the manufacturing process of each electrode member. Referring to FIG. 2, electrode members 21 to 23 are electrode members that are sequentially stacked in the order of electrode members 21, 22, and 23. As illustrated, the electrode members 21 to 23 are continuously manufactured. In FIG. 2, a state before the electrode members 21 to 23 are cut at the product width A is shown.

  The electrode members 21 to 23 are cut into a product width A by a rotary cutting blade (FIG. 4) described later. In addition to the step of cutting the electrode members 21 to 23, the electrode members 21 to 23 are provided on the protruding portions of the electrode sheet (in this example, the negative electrode sheet) using a rotary tab cutting blade (FIG. 5) described later. Tabs 31 to 33 each having a width C are formed at a predetermined interval B (B> A). Thereby, the tabs 31 to 33 can be offset with respect to the stacking direction when the electrode members 21 to 23 are stacked. This point will be described in detail later.

  FIG. 3 is a diagram schematically showing a cross section taken along line III-III in FIG. Referring to FIG. 3, electrode member 22 includes a positive electrode sheet 41, a negative electrode sheet 43, and separators 42 and 44. The positive electrode sheet 41 is formed, for example, by applying a positive electrode active material layer to the front and back surfaces of an aluminum alloy foil sheet.

  The negative electrode sheet 43 is formed, for example, by applying a negative electrode active material layer to the front and back surfaces of a copper foil sheet. A tab 32 (FIG. 2) is formed on one side of the negative electrode sheet 43. The tab 32 is formed in an uncoated portion where the negative electrode active material layer is not applied. The separators 42 and 44 are provided on both surfaces of the negative electrode sheet 43. Separator 42,44 is constituted by a porous insulating layer, for example.

  4 is a cross-sectional view of a rotary cutting blade for cutting the electrode members 21 to 23 into the product width A. FIG. Referring to FIG. 4, this cutting blade 50 includes a shaft portion 51 and blades 52 and 53. The blades 52 and 53 are provided 180 degrees apart from each other in the circumferential direction of the shaft portion 51, and each blade 52 and 53 is formed to extend in the axial direction. The size of the cutting blade 50 is determined so that the distance between the blade 52 and the blade 53 along the circumferential direction of the shaft portion 51 is A.

  The electrode members 21 to 23 can be cut into the product width A by the cutting blade 50 by rotating the cutting blade 50 in synchronization with the movement of the electrode members 21 to 23 shown in FIG.

  FIG. 5 is a cross-sectional view of a rotary tab cutting blade for forming tabs 31 to 33 on electrode members 21 to 23, respectively. Referring to FIG. 5, the tab cutting blade 60 includes a shaft portion 61 and blades 62 and 63. The blades 62 and 63 are provided 180 degrees apart from each other in the circumferential direction of the shaft portion 61, and each blade 62 and 63 cuts a part of the electrode protruding portion of the electrode member (in this example, the protruding portion of the negative electrode sheet). By doing so, a tab is formed in the non-cut portion. Specifically, when the tab cutting blade 60 rotates in synchronization with the cutting blade 50 (FIG. 4), each of the blades 62 and 63 has tabs 31 to 31 having a width C on the negative electrode sheet protruding portions of the electrode members 21 to 23. It is formed around the shaft portion 61 so that 33 is formed at every distance B (B> A).

  Referring again to FIG. 2, the cutting blade 50 (FIG. 4) and the tab cutting blade 60 (FIG. 5) are rotated by the cutting blade 50 in synchronization with the movement of the electrode members 21 to 23 in the row direction. While cutting the electrode members 21 to 23 to the product width A, tabs 31 to 33 can be formed on the negative electrode sheet protruding portions of the electrode members 21 to 23, respectively.

  When the electrode members 21 to 23 are sequentially stacked by forming the tabs 31 to 33 having the width C in the continuous electrode members 21 to 23 before cutting at every distance B (B> A), the tabs 31 to 33 are It can be offset in the planar direction of the electrode member. If a plurality of electrode members are stacked and the tabs of the electrode members are formed in a line in the stacking direction, a clamp and a new stack are stacked similarly to the stacking method described in Patent Document 1 above. Interference with the tab of the electrode member. As a result, the tab and the electrode member are bent, and the adhesion between the electrodes is lowered. As a result, the resistance of the battery is increased and the battery performance may be lowered.

  Therefore, in the method for stacking the assembled batteries according to this embodiment, the tabs 31 to 33 of the electrode members 21 to 23 are offset in the plane direction of the electrode members, and the electrode members 21 to 23 are sequentially stacked. Accordingly, when the electrode members 21 to 23 are stacked, the electrode members 21 to 23 can be stacked without the tabs of the stacked electrode members interfering with the clamp.

  FIG. 6 is a view showing the arrangement relationship of the tabs 31 and 32 when the electrode member 22 is stacked on the electrode member 21. Referring to FIG. 6, by cutting electrode members 21, 22 using cutting blade 50 (FIG. 4) and tab cutting blade 60 (FIG. 5), tab 32 is flat on the electrode member with respect to tab 31. It is arranged offset by a distance (B-A) in the direction. The tabs 31 and 32 overlap by a width X in the planar direction of the electrode member. In other words, the distance B between the tabs 31 and 32 and the tab width C before product cutting are determined with respect to the product width A of the electrode members 21 to 23 so that the tabs 31 and 32 overlap by a predetermined width X. .

  As will be described later, in this overlapping portion, the tab 32 is clamped by using a clamping jig and the tabs 31 and 32 are joined to form the current collector of the electrode body 10. For this reason, with respect to the lengths B and C in the tab cutting blade 60, the width X = C− (B−A) is set to be larger than, for example, 2 mm in order to ensure the bonding strength of the tabs 31 and 32 in the overlapping portion. In addition, it is preferable to determine the lengths B and C with respect to the product width A.

  FIGS. 7 to 10 are diagrams showing the arrangement of the tabs and the clamping operation when the electrode members 21 to 23 are stacked. Referring to FIG. 7, an electrode member having tab 32 while fixing tab 31 (electrode member 21) with clamp 71 at an end portion (the side opposite to tab 32) of tab 31 of electrode member 21 (not shown). 22 (not shown) is laminated on the electrode member 21. The tab 32 has an overlapping portion with the tab 31 and is offset in the planar direction with respect to the tab 31 so as not to interfere with the clamp 71 fixing the tab 31 (electrode member 21).

  Referring to FIG. 8, when electrode member 22 (not shown) having tab 32 is laminated on electrode member 21 (not shown), tab 32 is clamped 72 at the overlapping portion of tab 31 and tab 32. (Electrode member 22) is fixed.

  Referring to FIG. 9, when tab 32 is fixed with clamp 72, clamp 71 that has fixed tab 31 is removed. The clamp 72 also serves as a joining jig that joins the tab 31 and the tab 32 at the overlapping portion by energization of the overlapping portion between the tab 31 and the tab 32 or ultrasonic vibration. Are joined at the overlapping portion.

  Referring to FIG. 10, an electrode member 23 (not shown) having a tab 33 is stacked on the electrode member 22 while the tab 32 is fixed by a clamp 72 at an overlapping portion of the tab 31 and the tab 32. The tab 33 overlaps with the tab 32 and is offset in the planar direction with respect to the tab 32 so as not to interfere with the clamp 72 fixing the tab 32 (electrode member 22).

  As described above, when the electrode members 21 to 23 are stacked, the electrode members 21 to 23 can be stacked without interference between the clamps 71 and 72 and the tab of the newly stacked electrode member.

  FIG. 11 is a flowchart illustrating the procedure of the method for manufacturing the assembled battery according to the present embodiment. Referring to FIG. 11, first, initial value 1 is set to counter i (step S10). Next, the i-th electrode member (that is, the first electrode member of the first layer) is disposed (step S20). Next, the tab of the i-th electrode member (first electrode member) is fixed by the first clamp (step S30).

  Subsequently, the (i + 1) th electrode member is laminated (step S40). Here, the tab of the (i + 1) th electrode member has an overlapping portion with the tab of the i-th electrode member, and the i-th electrode so as not to interfere with the first clamp fixing the tab of the i-th electrode member. A predetermined amount is offset in the plane direction with respect to the tab of the member.

  When the (i + 1) th electrode member is laminated, it is determined whether or not the lamination of all the electrode members is completed (step S50). If it is determined that all electrode members have been stacked (YES in step S50), the first clamp is released (step S60), and the process proceeds to the end.

  If it is determined in step S50 that the stacking of all the electrode members has not been completed (NO in step S50), the (i + 1) th (i + 1) th electrode portion is overlapped with the i-th electrode member tab. ) The tab of the electrode member is fixed by the second clamp (step S70). When the tab of the (i + 1) th electrode member is fixed by the second clamp, the first clamp that has fixed the i-th electrode member is released (step S80).

  Although no particular treatment is shown, at this stage, by applying electric current or ultrasonic vibration from the first clamp to the overlapping portion of the tab of the (i + 1) th electrode member and the tab of the i-th electrode member, In the overlapping portion, the tab of the (i + 1) th electrode member and the tab of the i-th electrode member are joined to form a current collector.

  Next, the (i + 2) th electrode member is laminated (step S90). Here, the tab of the (i + 2) th electrode member has an overlapping portion with the tab of the (i + 1) th electrode member, and does not interfere with the second clamp fixing the tab of the (i + 1) th electrode member. Further, it is offset by a predetermined amount in the plane direction with respect to the tab of the (i + 1) th electrode member.

  When the (i + 2) th electrode member is laminated, it is determined whether or not the lamination of all the electrode members is completed (step S100). If it is determined that all electrode members have been stacked (YES in step S100), the second clamp is released (step S110), and the process proceeds to the end.

  If it is determined in step S100 that the stacking of all electrode members has not been completed (NO in step S100), the overlapping portion of the tab of the (i + 2) th electrode member and the tab of the (i + 1) th electrode member (I + 2) The tab of the electrode member is fixed by the first clamp (step S110). In place of the first clamp, a third clamp different from the second clamp may be used. Then, when the tab of the (i + 2) th electrode member is fixed by the first clamp, the second clamp that has fixed the (i + 1) th electrode member is released (step S130).

  Although no particular treatment is shown, at this stage, a current or ultrasonic vibration is applied from the second clamp to the overlapping portion of the tab of the (i + 2) th electrode member and the tab of the (i + 1) th electrode member. As a result, the tab of the (i + 2) th electrode member and the tab of the (i + 1) th electrode member are joined at the overlapping portion, thereby forming a current collector.

  Then, the counter i is incremented by two (step S140), and the process returns to step S40.

  As described above, in this embodiment, the tab of the (i + 1) th electrode member laminated on the i-th electrode member is not interfered with the clamp fixing the tab of the i-th electrode member. Since it is offset with respect to the tab of the i electrode member, the (i + 1) th electrode member can be laminated on the upper part of the ith electrode member without the tab of the (i + 1) th electrode member interfering with the clamp. Therefore, according to this embodiment, it is possible to suppress bending of the electrode member during stacking of the electrode members while suppressing displacement of the electrode stack. As a result, it can suppress that battery performance falls by the adhesive fall of electrodes.

  In the above embodiment, the assembled battery is configured by laminating a plurality of sheet-like electrode members each including the positive electrode sheet 41 and the negative electrode sheet 43. The present invention can also be applied to a manufacturing method in which an assembled battery is configured by stacking electrode sheets themselves (a positive electrode sheet and a negative electrode sheet) instead of stacking such modularized electrode members.

  FIG. 12 is a cross-sectional view of positive electrode sheets and negative electrode sheets that are alternately stacked. Referring to FIG. 12, negative electrode sheet member 80 includes a negative electrode sheet 43 and separators 42 and 44. A tab 32 is formed on one side of the negative electrode sheet 43. A tab 81 is also formed on one side of the positive electrode sheet 41.

  The assembled battery is configured by alternately stacking the negative electrode sheet member 80 and the positive electrode sheet 41. The negative electrode sheet member 80 and the positive electrode sheet 41 are alternately laminated so that the tab 32 of the negative electrode sheet member 80 and the tab 81 of the positive electrode sheet 41 protrude in opposite directions.

  The tab 32 of each negative electrode sheet member 80 is provided so as to have an offset in the plane direction with respect to the tab 32 of the lower layer negative electrode sheet member 80, similarly to the electrode member in the above embodiment. Also about the positive electrode sheet 41, the tab 81 of each positive electrode sheet 41 is provided so that it may have an offset in a planar direction with respect to the tab 81 of the lower layer positive electrode sheet 41. FIG.

  Regarding the method of laminating the negative electrode sheet member 80 and the positive electrode sheet 41, the tabs 32 of the negative electrode sheet member 80 and the tabs 81 of the positive electrode sheet 41 that are laminated are clamped simultaneously on both sides of the laminate, and the next negative electrode sheet member 80. And the positive electrode sheet 41 is laminated | stacked. As described above, the tabs 32 of the negative electrode sheet members 80 are offset from each other, and the tabs 81 of the positive electrode sheets 41 are also offset from each other. Therefore, the negative electrode sheet members 80 and the positive electrode sheets 41 are alternately stacked. In this case, the negative electrode sheet member 80 and the positive electrode sheet 41 can be stacked without the tabs 32 and 81 interfering with the clamp.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is shown not by the above description of the embodiment but by the scope of claims, and is intended to include all modifications within the meaning and scope equivalent to the scope of claims.

  DESCRIPTION OF SYMBOLS 10 Electrode body, 12, 31-33, 81 Tab, 21-23 Electrode member, 41 Positive electrode sheet, 42, 44 Separator, 43 Negative electrode sheet, 50 Cutting blade, 51, 61 Shaft part, 52, 53, 62, 63 blade , 60 Tab cutting blade, 71, 72 Clamp, 80 Negative electrode sheet member.

Claims (1)

A method of manufacturing an assembled battery for forming an assembled battery by laminating a plurality of sheet-like members each constituting an electrode,
Each of the plurality of sheet-like members includes a tab protruding from a part of one side of the sheet-like member,
Laminating the first sheet-like member;
Fixing a first tab, which is the tab of the first sheet-like member, with a first clamp;
Laminating a second sheet-like member on top of the first sheet-like member while fixing the first tab with the first clamp,
The second tab which is the tab of the second sheet-like member has an overlapping portion with the first tab and does not interfere with the first clamp fixing the first tab. Is offset in a planar direction with respect to the first tab, and
A method for manufacturing an assembled battery, comprising: fixing the second tab with a second clamp at the overlapping portion.

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