Soft package battery module and grouping method thereof, battery pack and equipment using soft package battery module as power supply

Abstract

The invention discloses a soft package battery module and a grouping method thereof, a battery pack and equipment using the soft package battery module as a power supply. The grouping method of the soft package battery module comprises the following steps: connecting tabs of at least two battery monomers to enable the at least two battery monomers to jointly form a battery connection group; and folding the battery connection group so that the at least two battery cells are stacked and arranged. According to the grouping method of the soft package battery module, the tabs of the plurality of battery monomers are connected to form the battery connection group, and then the battery connection group is folded, so that the battery monomers can be grouped without a wire harness isolation plate, and the production efficiency is high. And a wire harness isolation plate is omitted, so that the length of the soft package battery module is not limited by the length of the wire harness isolation plate, and the soft package battery modules with different lengths can be conveniently produced.

Description

[0001] This divisional application is based on an invention with the application number 201911134962.5, the application date of November 19, 2019, the applicant Contemporary Amperex Technology Co., Limited, and the invention title "Soft-pack battery module and its grouping method, battery pack, and device using the soft-pack battery module as a power source". Technical Field

[0002] The present invention relates to the technical field of batteries, and particularly relates to a soft-pack battery module and its grouping method, a battery pack, and a device using the soft-pack battery module as a power source. Background Art

[0003] The tab of a soft-pack battery cell has relatively weak mechanical strength. When forming a group, it usually needs to rely on a copper bar fixed on a wire harness separator for support. Generally, the tab of the soft-pack battery cell is first passed through the wire harness separator and then placed on the copper bar for welding. When the number of series of the module is relatively high, the length of the module is also relatively long. At this time, more tabs need to pass through the wire harness separator, which makes the operation difficult and the injection molding of the relatively long wire harness separator more difficult, so the cost is very high. Summary of the Invention

[0004] The purpose of the present invention is to provide a soft-pack battery module and its grouping method, a battery pack, and a device using the soft-pack battery module as a power source to improve production efficiency.

[0005] The first aspect of the present invention provides a grouping method for a soft-pack battery module. The battery module includes at least two battery cells. The battery cells are soft-pack batteries and have tabs, and the method includes:

[0006] Connecting the tabs of at least two battery cells so that at least two battery cells jointly form a battery connection group;

[0007] Folding the battery connection group so that at least two battery cells are stacked and arranged.

[0008] In some embodiments, connecting the tabs of at least two battery cells includes using a connecting piece to connect the tabs of at least two battery cells.

[0009] In some embodiments, welding the connecting piece to the tab.

[0010] In some embodiments, the grouping method further includes, before connecting the tabs of at least two battery cells, laying the large surfaces of at least two battery cells flat and arranging them in at least one row in sequence.

[0011] In some embodiments, the grouping method further includes, before connecting the tabs of at least two battery cells, evenly dividing at least two battery cells into at least two groups of battery cells; laying the large faces of the battery cells in each group of battery cells flat and arranging them in at least one row in sequence; and stacking the groups of battery cells in the thickness direction of the battery cells.

[0012] In some embodiments, connecting the tabs of at least two battery cells includes connecting the tabs of the battery cells at corresponding positions of at least two groups of battery cells.

[0013] In some embodiments, the tab extends along a first direction with respect to the battery cell, a second direction is perpendicular to the first direction, and the folded battery connection group includes folding the battery connection group along a first folding line in the first direction and / or along a second folding line in the second direction.

[0014] In some embodiments, the folded battery connection group includes folding the battery connection group at least twice along the first folding line in the first direction; and / or, the folded battery cell connection group includes folding the battery connection group at least twice along the second folding line in the second direction.

[0015] In some embodiments, in at least two folds, the adjacent two folding directions are opposite.

[0016] In some embodiments, in at least two folds, there is a battery cell or at least two battery cells spaced between the folding lines of the adjacent two folds.

[0017] In some embodiments, the grouping method further includes, after forming the battery connection group, attaching a first insulating film to both sides of the battery connection group in the thickness direction of the battery cells and folding the first insulating film and the battery connection group together.

[0018] In some embodiments, the first insulating film is coated on the battery connection group by using a hot pressing technique.

[0019] In some embodiments, the grouping method further includes, in the thickness direction of the battery cells, laying a heating film on at least one of the first insulating films on both sides of the battery connection group, and folding the first insulating film, the heating film, and the battery connection group together.

[0020] In some embodiments, the grouping method further includes attaching a second insulating film on one side of the heating film, and folding the first insulating film, the heating film, the second insulating film, and the battery connection group together.

[0021] In some embodiments, the grouping method further includes connecting a circuit board to the battery connection group before attaching the first insulating film, attaching the first insulating film to the battery connection group and the circuit board, and folding the battery connection group, the first insulating film, and the circuit board together.

[0022] In a second aspect of the present invention, a pouch battery module is provided, which includes at least two battery stack layers arranged in a stacked manner in the thickness direction of the battery cells and a plurality of connecting pieces. The plurality of connecting pieces include inter-layer connecting pieces, and at least a part of the inter-layer connecting pieces is coated with an insulating material and has a bent structure to connect the battery cells respectively located on two battery stack layers in the thickness direction.

[0023] In some embodiments, the inter-layer connecting piece includes two end segments and an intermediate segment connecting the two end segments, and the intermediate segment has an arc-shaped bent structure.

[0024] In some embodiments, the end segment has a planar structure; alternatively, the end segment has an arc-shaped bent structure.

[0025] In some embodiments, the plurality of connecting pieces further include end connecting pieces, and the end connecting pieces are connected to the tabs of the battery cells located on the uppermost layer or the lowermost layer in the thickness direction and extend out of the outer side of the pouch battery module, and the end connecting pieces form the output terminals of the pouch battery module.

[0026] In some embodiments, the end connecting piece has a planar structure.

[0027] In some embodiments, each battery stack layer includes one battery cell or two or more battery cells.

[0028] In some embodiments, the pouch battery module further includes a first insulating film respectively attached to both sides of the battery stack layer and the connecting pieces. The connecting pieces further include intra-layer connecting pieces, and the intra-layer connecting pieces connect the tabs of adjacent battery cells on the battery stack layer. The first insulating film includes a bent insulating film attached to the inter-layer connecting piece and planar insulating films disposed on both sides of the bent insulating film and attached to the battery stack layer and the intra-layer connecting piece, and the bent insulating film connects the planar insulating films.

[0029] In some embodiments, the pouch battery module further includes a heating film attached to the first insulating film, and the heating film includes a bent heating film attached to the bent insulating film and a planar heating film attached to the planar insulating film.

[0030] In some embodiments, the pouch battery module further includes a second insulating film attached to the heating film, and the second insulating film includes a bent insulating film attached to the bent heating film and a planar insulating film attached to the planar heating film.

[0031] In some embodiments, the pouch battery module further includes a circuit board electrically connected to the connecting pieces, and the circuit board includes a circuit board planar segment extending along the battery stack layer and a circuit board bent segment disposed between two adjacent circuit board planar segments.

[0032] The third aspect of the present invention provides a battery pack, which includes a box body and the soft-pack battery module according to any one of the second aspect of the present invention, and the soft-pack battery module is accommodated in the box body.

[0033] The fourth aspect of the present invention provides a device using the soft-pack battery module as a power source, which includes a driving device and the soft-pack battery module according to any one of the second aspect of the present invention. The driving device is used to provide driving force for the device, and the battery module is configured to provide electrical energy to the driving device.

[0034] Based on the technical solution provided by the present invention, the grouping method of the soft-pack battery module first connects the tabs of multiple battery cells to form a battery connection group, and then folds the battery connection group, so as to group the battery cells without a wire harness separator, and the production efficiency is high. Moreover, the wire harness separator is omitted, so that the length of the soft-pack battery module of the present invention is not limited by the length of the wire harness separator. Therefore, it is convenient to produce soft-pack battery modules of different lengths.

[0035] Other features and advantages of the present invention will become clear through the following detailed description of the exemplary embodiments of the present invention with reference to the accompanying drawings. Description of the Drawings

[0036] The drawings described herein are used to provide a further understanding of the present invention, and constitute a part of this application. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0037] Figure 1 is a schematic structural diagram of a vehicle according to an embodiment of the present invention;

[0038] Figure 2 is Figure 1 a schematic structural diagram of the battery pack in

[0039] Figure 3 is a schematic structural diagram of a battery cell according to an embodiment of the present invention;

[0040] Figure 4 is a schematic structural diagram of the battery connection group according to an embodiment of the present invention;

[0041] Figure 5 is for Figure 4 an explosion schematic diagram of hot pressing the battery connection group shown in

[0042] Figure 6 is for Figure 4 a three-dimensional structural schematic diagram of the soft-pack battery module formed by folding the battery connection group shown in

[0043] Figure 7 is Figure 6 a sectional view of the soft-pack battery module shown in

[0044] Figure 8 Schematic top view structure of the soft-pack battery module according to another embodiment of the present invention;

[0045] Figures 9 to 13 Schematic diagram of the grouping method of the soft-pack battery module according to another embodiment of the present invention;

[0046] Figures 14 to 17 Schematic diagram of the grouping method of the soft-pack battery module according to yet another embodiment of the present invention;

[0047] Figure 18 Schematic diagram of the structure of another battery cell according to an embodiment of the present invention;

[0048] Figure 19 Schematic diagram of the structure of another connecting piece according to an embodiment of the present invention;

[0049] Figures 20 to 24 For Figure 18 Schematic diagram of the method for grouping the battery cells shown;

[0050] Figures 25 to 27 For Figure 18 Another schematic diagram of the method for grouping the battery cells shown.

[0051] Each reference numeral represents:

[0052] 1. Soft-pack battery module;

[0053] 11. Battery cell;

[0054] 111. Negative electrode tab; 112. Positive electrode tab;

[0055] 12. Connecting piece; 12A. Welding area;

[0056] 121. Interlayer connecting piece; 1211. End segment; 1212. Intermediate segment; 122. End connecting piece; 123. Intralayer connecting piece;

[0057] 13. First insulating film;

[0058] 14. Heating film;

[0059] 15. Circuit board;

[0060] 16. Second insulating film;

[0061] 2. Upper box body;

[0062] 3. Lower box body;

[0063] 10. Battery pack;

[0064] 20. Vehicle body;

[0065] X, the first direction;

[0066] Y, the second direction;

[0067] Z, the thickness direction of the battery cell;

[0068] P, the battery connection group;

[0069] Q, the battery stack layer;

[0070] I, the first folding line;

[0071] J, the second folding line. Detailed implementation manners

[0072] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and in no way limits the present invention and its application or use. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0073] Unless otherwise specifically stated, the relative arrangements of components and steps, numerical expressions and values set forth in these embodiments do not limit the scope of the present invention. At the same time, it should be understood that for the sake of description, the dimensions of the various parts shown in the drawings are not drawn in actual proportional relationship. Technologies, methods and devices known to those of ordinary skill in the relevant art may not be discussed in detail, but where appropriate, the technologies, methods and devices should be regarded as part of the authorization specification. In all the examples shown and discussed here, any specific value should be construed as merely exemplary and not as a limitation. Therefore, other examples of the exemplary embodiments may have different values. It should be noted that: like reference numerals and letters denote like items in the following drawings, and thus, once an item is defined in one drawing, it does not need to be further discussed in subsequent drawings.

[0074] For ease of description, spatial relative terms such as "above", "over", "on the upper surface", "upper" etc. can be used here to describe the spatial positional relationship between a device or feature shown in the figure and other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation in addition to the orientation depicted in the figure for the device. For example, if the device in the attached drawing is inverted, a device described as "above" or "over" other devices or structures will then be positioned "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both the orientations of "above" and "below". The device can also be positioned in other different ways, and corresponding interpretations are made for the spatial relative descriptions used here.

[0075] An embodiment of the present invention provides a device using a pouch battery module 1 as a power source, a battery pack 10, a pouch battery module 1, and a grouping method for the pouch battery module 1. Among them, the device using the pouch battery module 1 as a power source includes the pouch battery module 1 and a driving device for providing driving force for the device, and the pouch battery module 1 supplies electrical energy to the driving device. The driving force of the device can be all electrical energy, or part of it can be electrical energy and part of it can be other energy sources. For example, the device can also include a power source such as an engine that provides mechanical energy. As long as the device using the pouch battery module 1 as a power source is within the protection scope of the present invention.

[0076] The device of the embodiment of the present invention can be a mobile device such as a vehicle, a ship, a small aircraft, etc. Taking a vehicle as an example, the vehicle of the embodiment of the present invention can be a new energy vehicle. The new energy vehicle can be a pure electric vehicle, or a hybrid vehicle or an extended-range vehicle. As Figure 1 shown, the vehicle includes a battery pack 10 and a vehicle body 20. The battery pack 10 is disposed inside the vehicle body 20 and includes at least one pouch battery module 1. The vehicle body 20 is provided with a driving motor, and the driving motor is electrically connected to the battery pack 10. The battery pack 10 supplies electrical energy to the driving motor, and the driving motor is connected to the wheels on the vehicle body 20 through a transmission mechanism to drive the vehicle to move forward. Specifically, the battery pack 10 can be horizontally disposed at the bottom of the vehicle body 20.

[0077] The battery pack 10 of the embodiment of the present invention includes at least one pouch battery module 1. Specifically in this embodiment, as Figure 2As shown in the figure, the battery pack 10 of this embodiment includes a plurality of pouch battery modules 1 and a box body for accommodating the plurality of pouch battery modules 1. The box body has an accommodation cavity, and the plurality of pouch battery modules 1 are arranged in the accommodation cavity. Specifically, the box body of this embodiment is a box-shaped box body and includes a lower box body 3 for accommodating the pouch battery module 1 and an upper box body 2 that covers the lower box body 3. In embodiments not shown in other drawings, the box body can also be other shapes such as a frame-shaped box body or a disc-shaped box body.

[0078] In this embodiment, as Figure 3 shown, the battery cell 11 includes a positive electrode tab 111 and a negative electrode tab 112, and in this embodiment, both the positive electrode tab 111 and the negative electrode tab 112 are located at the same end of the battery cell 11. And the tabs extend along the first direction X with respect to the battery cell 11, and the second direction Y is perpendicular to the first direction X.

[0079] The method of forming a plurality of such battery cells 11 into a pouch battery module 1 is as Figure 4 and Figure 5 shown. Specifically, the large surfaces of a plurality of battery cells 11 are laid flat and arranged in two rows in sequence; the tabs of the plurality of battery cells 11 are connected by connecting pieces 12 so that the plurality of battery cells 11 jointly form a battery connection group P; the battery connection group P is folded so that the plurality of battery cells 11 are stacked and arranged. The method of forming the pouch battery module 1 in this embodiment first connects the tabs of a plurality of battery cells 11 to form a battery connection group P and then folds the battery connection group P, thereby realizing the grouping of battery cells 11 without a wire harness isolation board, and the production efficiency is high.

[0080] In other embodiments, the tabs of a plurality of battery cells 11 can also be directly connected without using connecting pieces.

[0081] In order to enhance the insulation between the connecting pieces 12 and the insulation between the battery cells 11, as Figure 5 shown, the method of forming the pouch battery module 1 in this embodiment further includes attaching first insulating films 13 to both sides of the battery connection group P in the thickness direction Z of the battery cell 11 and folding the first insulating films 13 and the battery connection group P together. Specifically, the first insulating films 13 are coated on the battery connection group P by using a hot pressing technique. The first insulating films 13 are attached to both the battery cell 11 and the connecting pieces 12 in this embodiment, and the first insulating films 13 connect the battery cell 11 and the connecting pieces 12 into one body, thus facilitating folding. Moreover, the first insulating films 13 are attached to both sides of the battery cell 11 to enhance the strength of the battery cell 11.

[0082] To achieve the integrated heating film function, the grouping method of this embodiment further includes sequentially laying a heating film 14 and a second insulating film 16 on the first insulating film 13, and folding the battery connection group P, the first insulating film 13, the heating film 14, and the second insulating film 16 together. Among them, the heating film 14 can be a heat-conducting aluminum plate.

[0083] After the battery connection group P is coated, as Figure 4 shown by the respective arrows in, the coated battery connection group P is folded multiple times along the first folding line I in the first direction X to form the soft-pack battery module 1.

[0084] In the above-mentioned multiple folds, the directions of adjacent folds are opposite. Specifically, a bending device is used to perform serpentine bending on the coated battery connection group P.

[0085] As Figure 6 and Figure 7 shown, the soft-pack battery module 1 formed by the grouping method of this embodiment includes at least two battery stacking layers Q arranged in a stack in the thickness direction Z of the battery cell 11 and a plurality of connecting pieces 12. The plurality of connecting pieces 12 include an interlayer connecting piece 121. The interlayer connecting piece 121 is at least partially coated with an insulating material and has a bent structure to connect the battery cells 11 respectively located on two battery stacking layers Q in the thickness direction Z. The soft-pack battery module 1 of this embodiment uses the interlayer connecting piece 121 coated with an insulating material to connect the battery cells 11 respectively located on two battery stacking layers Q, without the wire harness isolation board in the prior art, so that the length of the soft-pack battery module 1 of this embodiment is not limited by the length of the wire harness isolation board, and thus it is convenient to produce soft-pack battery modules 1 of different lengths.

[0086] As Figure 7 shown, the interlayer connecting piece 121 includes two end segments 1211 and an intermediate segment 1212 connecting the two end segments 1211. The intermediate segment 1212 has an arc-shaped bent structure. The two end segments 1211 are respectively connected to the battery cells 11 on two adjacent battery stacking layers Q. As Figure 4 shown, before grouping, the interlayer connecting piece 121 of this embodiment has a rectangular structure, and it is folded during the grouping process so that in the formed soft-pack battery module 1, the interlayer connecting piece 121 becomes a bent structure.

[0087] In this embodiment, the end segment 1211 has a planar structure. Such a setting makes the end segment 1211 directly fit on the tab of the battery cell 11, thereby reducing the volume of the entire soft-pack battery module 1.

[0088] At least a part of the interlayer connection piece 121 in this embodiment is coated with an insulating material to prevent short circuit caused by contact between two adjacent interlayer connection pieces 121 in the thickness direction Z of the battery cell 11. Specifically, as Figure 7 shown, at least a part refers to the outer side of the middle section 1212 of the interlayer connection piece 121.

[0089] As Figure 6 and Figure 7 shown, the multiple connection pieces 12 in this embodiment further include end connection pieces 122. The end connection pieces 122 are connected to the tabs of the battery cells 11 at the uppermost and lowermost layers in the thickness direction Z and extend out of the outer side of the soft-pack battery module 1. The end connection pieces 122 form the output end of the soft-pack battery module 1.

[0090] Specifically, the end connection piece 122 in this embodiment has a planar structure.

[0091] Combined with Figure 5 shown, it can be known from the grouping method of the soft-pack battery module 1 in this embodiment that the first insulating film 13 is attached to both sides of the interlayer connection piece 121 and bends together with the interlayer connection piece 121. Specifically, the soft-pack battery module 1 in this embodiment further includes the first insulating films 13 respectively attached to both sides of the battery stacking layer Q and the connection piece 12. The first insulating film 13 includes a bent insulating film attached to the interlayer connection piece 121 and planar insulating films disposed on both sides of the bent insulating film and attached to the battery stacking layer Q. The bent insulating film connects the planar insulating films.

[0092] In this embodiment, the soft-pack battery module 1 further includes a heating film 14 attached to the first insulating film 13. The heating film 14 includes a bent heating film attached to the bent insulating film and a planar heating film attached to the planar insulating film.

[0093] In this embodiment, the soft-pack battery module 1 further includes a second insulating film 16 attached to the heating film 14. The second insulating film 16 includes a bent insulating film attached to the bent heating film and a planar insulating film attached to the planar heating film.

[0094] As Figure 6 shown, the dimension of the soft-pack battery module 1 in the thickness direction of the battery cell 11 is the height of the soft-pack battery module 1, the dimension in the first direction X is the length of the soft-pack battery module 1, and the dimension in the second direction Y is the width of the soft-pack battery module 1.

[0095] Again, as Figure 4As shown, between the first folding lines I of two adjacent foldings in multiple foldings of this embodiment, one battery cell 11 is provided. Such a setting enables each battery stacking layer Q of the soft-pack battery module 1 of this embodiment to have one battery cell in the second direction Y. That is to say, in practical applications, the number of battery cells 1 between the first folding lines I between two foldings can be adjusted according to requirements, thereby adjusting the width of the soft-pack battery module 1.

[0096] In this embodiment, multiple battery cells 11 are placed flat and arranged in two rows. As Figure 6 shown, each formed battery stacking layer Q includes two battery cells 11 arranged in the first direction X.

[0097] In another embodiment, when forming a group, multiple battery cells 11 are placed flat and arranged in a row, and the soft-pack battery module 1 as Figure 8 shown will be formed. At this time, each battery stacking layer Q includes one battery cell 11.

[0098] In another embodiment, as Figure 9 shown, the large surfaces of multiple battery cells 11 are placed flat and arranged in two rows, and there is a certain distance between the battery cells 11 and the battery cells 11; between the tabs of adjacent battery cells 11, a connecting piece 12 is lapped, and the connecting piece 12 is welded to the tabs of the battery cells 11. One connecting piece 12 is welded to the tabs of four adjacent battery cells 11 respectively. As Figure 10 shown, then the first insulating film 13 is used to cover the upper and lower sides of the battery connection group P by hot pressing technology to ensure insulation between the connecting pieces 12 after forming a group. At this time, the electrical circuit of the entire module has been assembled. As Figure 11 shown, finally, the laid battery connection group P is folded along the first folding line I in the first direction X by an automated device to obtain the stacked soft-pack battery module 1.

[0099] Specifically in this embodiment, as Figure 11 shown by the arrow in, the battery connection group P is folded twice. And there are multiple battery cells 11 spaced between the folding lines of these two foldings. As Figure 12 and 13 shown, each battery stacking layer Q of the soft-pack battery module 1 formed by such folding includes multiple battery cells in the second direction Y. Therefore, the grouping method of this embodiment can adjust the number of folding times and the position of the folding line according to requirements to adjust the number of layers of the battery stacking layer Q of the soft-pack battery module 1 and the number of battery cells 11 on each battery stacking layer Q, so as to stack and form soft-pack battery modules 1 with different lengths and heights.

[0100] Compared with the connecting piece 12 of the embodiment shown in Figure 4 , Figure 9The connecting piece 12 of the illustrated embodiment is also rectangular, but wider. Therefore, in practical applications, the size of the connecting piece 12 can be adjusted according to actual requirements.

[0101] As Figures 11 to 13 shown, the multiple connecting pieces 12 of the soft-pack battery module 1 of this embodiment include interlayer connecting pieces 121, end connecting pieces 122, and in-layer connecting pieces 123. Among them, the interlayer connecting pieces 121 are coated with insulating materials and have a bent structure to connect the battery cells 11 on two battery stacking layers Q respectively in the thickness direction Z; the end connecting pieces 122 are connected to the tabs of the battery cells 11 on the uppermost and lowermost layers in the thickness direction Z and extend outside the soft-pack battery module 1, and the end connecting pieces 122 form the output end of the soft-pack battery module 1; the in-layer connecting pieces 123 connect the tabs of the battery cells 11 adjacent in the second direction Y.

[0102] Preferably, the grouping method of this embodiment further includes connecting a circuit board 15 to the battery connection group P, and the circuit board 15 is electrically connected to the multiple connecting pieces 12. Then, the first insulating film 13 is attached to the battery connection group P and the circuit board 15, and the battery connection group P, the first insulating film 13, and the circuit board 15 are folded together. Specifically, in this embodiment, the circuit board 15 can be an FPC, a PCB, an FFC, etc. The circuit board 15 is used for collecting information of the battery cells 11. Preferably, the circuit board 15 is a flexible circuit board, such as an FPC; the flexible circuit board has flexibility and a small volume, which can save internal space for the grouped battery module.

[0103] The circuit board 15 of the soft-pack battery module 1 formed by the grouping method of this embodiment includes a circuit board planar section extending along the battery stacking layer Q and a circuit board bent section provided between two adjacent circuit board planar sections.

[0104] To achieve the integrated heating function, the grouping method of this embodiment also includes sequentially laying a heating film 14 and a second insulating film 16 on the first insulating film 13, and folding the battery connection group P, the first insulating film 13, the circuit board 15, the heating film 14, and the second insulating film 16 together.

[0105] Specifically, the first insulating film 13 includes a bent insulating film attached to the interlayer connecting piece 121 and planar insulating films provided on both sides of the bent insulating film and attached to the battery stacking layer Q and the in-layer connecting piece 123, and the bent insulating film connects the planar insulating films.

[0106] Figures 14 to 17A grouping method showing another embodiment of the present invention. The grouping method of this embodiment includes evenly dividing at least two battery cells 11 into at least two battery cell groups; laying the large surfaces of the battery cells 11 in each battery cell group flat and arranging them in at least one row in sequence; stacking the battery cell groups in the thickness direction Z of the battery cells 11; and then connecting the tabs of the battery cells 11 by using connecting pieces 12.

[0107] Specifically, as Figure 16 shown in the enlarged structure of part M, the connecting piece 12 is placed between the two tabs of the upper and lower layers of the battery cells 11 in the two stacked battery cell groups and welded to realize the connection of the tabs.

[0108] After connecting the respective battery cells 11, a battery connection group P as shown in Figure 14 and Figure 15 is formed. The battery connection group P is a double-layer structure. Then, the battery connection group P is folded multiple times to form a soft-pack battery module 1 as shown in Figure 17 shown.

[0109] Similarly, the soft-pack battery module 1 includes at least two battery stacking layers Q stacked and arranged in the thickness direction Z of the battery cells 11 and a plurality of connecting pieces 12. The plurality of connecting pieces 12 include inter-layer connecting pieces 121. The inter-layer connecting pieces 121 are coated with an insulating material and are in a bent structure to connect the battery cells 11 respectively located on two battery stacking layers Q in the thickness direction Z. Specifically, the inter-layer connecting piece 121 includes two end segments 1211 and an intermediate segment 1212 connecting the two end segments 1211. The intermediate segment 1212 is in an arc-shaped bent structure. The two end segments 1211 are respectively connected to the battery cells 11 on two adjacent battery stacking layers Q.

[0110] Specifically in this embodiment, the end segment 1211 is a planar structure.

[0111] In some other embodiments, as Figure 18 shown, the positive tab 112 and the negative tab 111 of the battery cell 11 in this embodiment are respectively located at both ends of the battery cell 11. The extending direction of the tab with respect to the battery cell 11 is the first direction X, and the second direction Y is perpendicular to the first direction X.

[0112] Next, the grouping method for forming the soft-pack battery module 1 from the battery cell 11 will be described in detail according to Figures 19 to 27 this.

[0113] In one embodiment, as Figure 20 shown, a plurality of battery cells 11 are laid flat on a tooling, and a certain distance is left between adjacent battery cells 11. Then, the tabs of the battery cells 11 are connected by using a connecting piece 12 in a U-shaped structure as shown in Figure 19 to form a battery connection group P.

[0114] The connecting piece 12 has four welding areas 12A for welding with four adjacent tab ears. As Figure 21 shown, first fold the battery connection group P once along the first folding line I in the first direction X, and then fold the battery connection group P twice along the second folding line J in the second direction Y to form Figure 23 and Figure 24 the pouch battery module 1 shown.

[0115] Similarly, the pouch battery module 1 of this embodiment includes at least two battery stacking layers Q stacked and arranged in the thickness direction Z of the battery cells 11 and a plurality of connecting pieces 12. The plurality of connecting pieces 12 include interlayer connecting pieces 121. The interlayer connecting pieces 121 are coated with insulating materials and are in a bent structure to connect the battery cells 11 on two battery stacking layers Q respectively in the thickness direction Z.

[0116] Different from other embodiments, the two end segments 1211 of the interlayer connecting piece 121 of this embodiment and the middle segment 1212 connecting the two end segments 1211. The middle segment 1212 is in an arc-shaped bent structure. The two end segments 1211 are respectively connected to the battery cells 11 on two adjacent battery stacking layers Q. And the end segments 1211 are in an arc-shaped bent structure.

[0117] In another embodiment, as Figure 25 and Figure 26 shown, first place a plurality of battery cells 11 flat on the tooling. Then use the connecting piece 12 to connect the tab ears of adjacent battery cells 11 to form the battery connection group P. Then fold the battery connection group P multiple times along the first folding line I in the first direction X, and the folding directions of two adjacent folds are opposite during the multiple folds to form the pouch battery module 1 as Figure 27 shown.

[0118] Different from other embodiments, as Figure 27 shown, the two battery cells 11 on each battery stacking layer Q of the pouch battery module 1 of this embodiment are connected in parallel.

[0119] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them; although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that: still can modify the specific implementation manners of the present invention or perform equivalent replacements on some technical features; without departing from the spirit of the technical solutions of the present invention, they should all be covered within the scope of the technical solutions claimed by the present invention.

Claims

1. A method for assembling a soft-pack battery module, wherein the battery module (1) includes at least two battery cells (11), and the battery cells (11) are soft-pack batteries and have tabs. Characterized in that, Comprising: Dividing the at least two battery cells (11) into at least two groups of battery cells on average; Placing the large faces of the multiple battery cells (11) in each group of battery cells flat and arranging them in at least two rows in sequence, and the battery cells (11) in each of the at least two rows are arranged in one-to-one correspondence; Stacking the groups of battery cells in the thickness direction (Z) of the battery cells (11); Connecting the tabs of the at least two battery cells (11) so that the at least two battery cells (11) jointly form a battery connection group (P), and the tabs extend along a first direction (X) with respect to the battery cells (11), and a second direction (Y) is perpendicular to the first direction (X); Folding the battery connection group (P) so that the at least two battery cells (11) are stacked and arranged, and folding the battery connection group (P) includes folding the battery connection group (P) along a first folding line (I) in the first direction (X) and a second folding line in the second direction (Y), wherein folding the battery connection group (P) includes folding along the first folding line in the first direction (X) at least twice and folding the battery connection group (P) along the second folding line (J) in the second direction (Y) at least twice. In the at least two folds, there is a battery cell (11) or at least two battery cells (11) spaced between adjacent folding lines.

2. The method for assembling a soft-pack battery module according to claim 1, Characterized in that, Connecting the tabs of the at least two battery cells (11) includes connecting the tabs of the at least two battery cells (11) by using a connecting piece (12).

3. The method for assembling a soft-pack battery module according to claim 2, Characterized in that, Welding the connecting piece (12) to the tab.

4. The method for assembling a soft-pack battery module according to claim 1, Characterized in that, Connecting the tabs of the at least two battery cells (11) includes connecting the tabs of the battery cells (11) at corresponding positions of the at least two groups of battery cells.

5. The method for assembling a soft-pack battery module according to claim 1, Characterized in that, In the at least two folds, the adjacent two folding directions are opposite.

6. The method for assembling a soft-pack battery module according to any one of claims 1 to 5, Characterized in that, The assembling method further includes, after forming the battery connection group (P), on both sides of the battery connection group (P) in the thickness direction (Z) of the battery cells (11), attaching first insulating films (13) and folding the first insulating films (13) and the battery connection group (P) together.

7. The method for assembling a soft-pack battery module according to claim 6, Characterized in that, Coating the first insulating film (13) on the battery connection group (P) by using a hot pressing technique.

8. The method for assembling a pouch battery module according to claim 6, wherein, the assembling method further includes laying a heating film (14) on at least one side of the first insulating films on both sides of the battery connection group (P) in the thickness direction (Z) of the battery cell (11), and folding the first insulating film (13), the heating film (14) and the battery connection group (P) together.

9. The method for assembling a pouch battery module according to claim 8, wherein, the assembling method further includes attaching a second insulating film (16) on one side of the heating film (14), and folding the first insulating film (13), the heating film (14), the second insulating film (16) and the battery connection group (P) together.

10. The method for assembling a pouch battery module according to claim 6, wherein, the assembling method further includes connecting a circuit board (15) to the battery connection group (P) before attaching the first insulating film (13), attaching the first insulating film (13) to the battery connection group (P) and the circuit board (15), and folding the battery connection group (P), the first insulating film (13) and the circuit board (15) together.

11. A pouch battery module, wherein, it includes at least two battery stacking layers (Q) and a plurality of connecting pieces (12) arranged in a stacked manner in the thickness direction (Z) of the battery cell (11), the plurality of connecting pieces (12) includes an interlayer connecting piece (121), and at least part of the interlayer connecting piece (121) is coated with an insulating material and is in a bent structure to connect the battery cells (11) respectively located on two battery stacking layers (Q) in the thickness direction (Z).

12. The pouch battery module according to claim 11, wherein, the interlayer connecting piece (121) includes two end segments (1211) and an intermediate segment (1212) connecting the two end segments (1211), and the intermediate segment (1212) is in an arc-shaped bent structure.

13. The pouch battery module according to claim 12, wherein, the end segment (1211) is in a planar structure; or, the end segment (1211) is in an arc-shaped bent structure.

14. The pouch battery module according to claim 11, wherein, the plurality of connecting pieces (12) further includes an end connecting piece (122), the end connecting piece (122) is connected to the ear of the battery cell (11) located in the uppermost layer or the lowermost layer in the thickness direction (Z) and extends outside the pouch battery module (1), and the end connecting piece (122) forms the output end of the pouch battery module (1).

15. The pouch battery module according to claim 14, wherein, the end connecting piece (122) is in a planar structure.

16. The pouch battery module according to claim 11, wherein, each battery stacking layer (Q) includes one battery cell (11) or two or more battery cells (11).

17. The pouch battery module according to claim 11, wherein, the pouch battery module (1) further includes a first insulating film (13) respectively attached to both sides of the battery stack layer (Q) and the connecting piece (12). The connecting piece (12) further includes an in-layer connecting piece (123). The in-layer connecting piece (123) connects the electrode tabs of adjacent battery cells (11) on the battery stack layer (Q). The first insulating film (13) includes a bent insulating film attached to the inter-layer connecting piece (121) and planar insulating films disposed on both sides of the bent insulating film and attached to the battery stack layer (Q) and the in-layer connecting piece (123). The bent insulating film connects the planar insulating films.

18. The pouch battery module according to claim 17, wherein, the pouch battery module (1) further includes a heating film (14) attached to the first insulating film (13). The heating film (14) includes a bent heating film attached to the bent insulating film and a planar heating film attached to the planar insulating film.

19. The pouch battery module according to claim 18, wherein, the pouch battery module (1) further includes a second insulating film (16) attached to the heating film (14). The second insulating film (16) includes a bent insulating film attached to the bent heating film and a planar insulating film attached to the planar heating film.

20. The pouch battery module according to claim 11, wherein, the pouch battery module (1) further includes a circuit board (15) electrically connected to the connecting piece (12). The circuit board (15) includes a circuit board planar section extending along the battery stack layer (Q) and a circuit board bent section disposed between two adjacent circuit board planar sections.

21. A battery pack, wherein, it includes a box body and the pouch battery module according to any one of claims 11 to 20. The pouch battery module is accommodated in the box body.

22. A device using the pouch battery module as a power source, wherein, it includes a driving device and the pouch battery module according to any one of claims 11 to 21. The driving device is used to provide driving force for the device, and the battery module is configured to supply electric energy to the driving device.

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