Battery module, battery pack and battery module assembling method

Abstract

The invention provides a battery module, a battery pack and a battery module assembling method, the two ends of the battery module in a first direction are provided with end plates, the two ends of the battery module in a second direction are provided with side plates, the end plates are connected with the side plates, and the end plates are provided with first fixing holes used for being connected with a box body; the battery module comprises a plurality of battery cells and module buffer pieces which are sequentially arranged in the first direction, and one module buffer piece is arranged between every two adjacent battery cells. According to the battery module, the end plates are directly connected with the side plates, so that the overall structural strength of the module is improved, the end plates are connected with the box body through the first fixing holes, connecting glue between the battery module and the box body can be omitted, the assembly process is optimized, the assembly time is saved, the pre-tightening force can be preset in advance, and the assembly precision is ensured; and meanwhile, the module buffer piece is arranged between the two adjacent battery cells of the battery module, so that the impact load of expansive force generated in the battery circulation process on the box body can be effectively reduced.

Description

Technical Field

[0001] The present application relates to the technical field of power batteries, and in particular to a battery module, a battery pack, and a battery module assembly method. Background Art

[0002] CTP (Cell to Pack) technology is a battery technology design concept that directly integrates single cells (Cell) into battery packs (Pack) through precise design and layout to reduce unnecessary components in the battery pack, such as module frames, conductive tapes, insulating materials, etc., thereby increasing energy density, reducing production costs and improving safety.

[0003] In the existing CTP (Cell to Pack) structure battery pack, the battery module and the box are bonded with structural adhesive. The gluing process is complicated and requires precise control of the glue application amount and gluing trajectory. The process is time-consuming and the production efficiency needs to be improved. This assembly method also requires accurate calculation of the module entry pre-tightening force when entering the box, which has high precision requirements and complex processes. In addition, the expansion force generated during the use of the battery causes a certain impact load on the crossbeam of the battery box, which requires a high strength of the box structure.

[0004] Therefore, it is necessary to design a new battery module to solve the above problems. Summary of the invention

[0005] In view of this, in order to overcome the defects of the prior art, the present invention provides a battery module, a battery pack and a battery module assembly method, which effectively solves the problems of long process time, low production efficiency and complex process caused by the assembly method of the battery module in the existing CTP battery pack, and can also solve the problem of impact load caused by expansion force on the cross beam of the battery box.

[0006] According to a first aspect of the present invention, there is provided a battery module, which can be connected to a battery pack box, wherein end plates are provided at both ends of the battery module in a first direction, and side plates are provided at both ends of the battery module in a second direction, the end plates are connected to the side plates, and the end plates are provided with a first fixing hole for connecting to the box; the battery module includes a plurality of battery cells and module buffers arranged in sequence along the first direction, and a module buffer is provided between two adjacent battery cells.

[0007] Preferably, the battery module also includes a wiring harness assembly located on the upper part of the battery cell, and connector plugs are provided at both ends of the wiring harness assembly in the first direction, and the end plate is provided with a second fixing hole, and the connector plug is connected to the end plate through the second fixing hole.

[0008] Preferably, the battery module further comprises an intermediate plate, which is arranged in the middle of the plurality of battery cells arranged along the first direction, and is provided with a third fixing hole for connecting to the box body and a positioning hole for positioning the wiring harness assembly.

[0009] Preferably, a positioning column is provided in the middle of the wiring harness assembly, the positioning column is provided on a side of the wiring harness assembly facing the battery core, and the positioning column is provided corresponding to the positioning hole; the wiring harness assembly is welded to the battery core.

[0010] Preferably, two end surfaces of the intermediate plate in the first direction are each provided with a module insulating member; and a module insulating member is provided between the battery core and the end plate.

[0011] Preferably, the battery module also includes an insulating strip arranged on the upper part of the wiring harness assembly and an insulating film arranged on the lower part of the battery cell, the insulating strip is provided with connecting glue on the side facing the wiring harness assembly, and the insulating strip is bonded to the wiring harness assembly; the insulating film is provided with connecting glue on the side facing the battery cell, and the insulating film is bonded to the battery cell.

[0012] Preferably, the module buffer is bonded to the battery cell by a connecting glue, and the connecting glue is arranged on two end surfaces of the module buffer that are arranged back to back, and the two end surfaces that are back to back are respectively in contact with two adjacent battery cells.

[0013] Preferably, the wiring harness assembly is also provided with an output pole protection cover and an output pole base which are clamped to each other at one end in the first direction; a clamping block and a connecting groove are respectively provided at the top and bottom of the output pole base, the output pole base is arranged on the end plate through the connecting groove, and a clamping buckle is provided at the end of the output pole protection cover facing the output pole base, and the output pole protection cover is clamped to the output pole base through the cooperation of the clamping buckle and the clamping block.

[0014] According to a second aspect of the present invention, a battery pack is provided, wherein the battery pack comprises the battery module as described above.

[0015] According to a third aspect of the present invention, a battery module assembly method is provided, wherein the battery module assembly method includes: performing appearance and electrical performance inspection on the battery cell; the module buffer enters the peeling paper station, the module buffer is bonded to the end surface of the battery cell, and one module buffer is arranged between adjacent battery cells; a plurality of the battery cells respectively form a first battery cell group and a second battery cell group, an intermediate plate is arranged between the first battery cell group and the second battery cell group, and the two end surfaces of the intermediate plate facing the first battery cell group and the second battery cell group are both pasted with a module insulating member with a single-sided adhesive backing; the first battery cell group , the second battery cell group, the middle plate, the side plate and the end plate are stacked in place, and the module is fixed to a set length using a fixture; structural adhesive is applied to the side plate to improve the connection strength between the side of the battery module and the side plate; after the end plate and the side plate are installed and fixed, the end plate and the side plate are welded, and the welds are inspected and cleaned; the output pole base is clamped to the end plate; the wiring harness assembly is assembled to the middle plate, and the output pole protective cover is clamped to the output pole base; the wiring harness assembly is welded to the first battery cell group and the second battery cell group, and the welds are inspected and cleaned; the insulating film and the insulating strip are respectively bonded to the bottom and top of the battery module.

[0016] According to the battery module of the present invention, the end plate is directly connected to the side plate, so the overall structural strength of the module is improved. The end plate is connected to the box body by utilizing the first fixing hole of the end plate, so that the connecting glue between the battery module and the box body can be omitted, the assembly process is optimized, the assembly time is saved, and the pre-tightening force can be preset in advance to ensure the assembly accuracy. At the same time, a module buffer is arranged between two adjacent battery cells of the battery module, which can effectively reduce the impact load of the expansion force generated during the battery cycle on the box body.

[0017] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, preferred embodiments are specifically cited below and described in detail with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0019] Figure 1 A schematic structural diagram of a battery module according to an embodiment of the present invention is shown;

[0020] Figure 2 An exploded view of a battery module according to an embodiment of the present invention is shown;

[0021] Figure 3A schematic structural diagram of an end plate according to an embodiment of the present invention is shown;

[0022] Figure 4 A top view showing an intermediate plate according to an embodiment of the present invention;

[0023] Figure 5 A side view showing a wiring harness assembly according to an embodiment of the present invention;

[0024] Figure 6 A schematic diagram showing the structure of an output pole protection cover according to an embodiment of the present invention is shown;

[0025] Figure 7 A schematic diagram showing the structure of an output pole base according to an embodiment of the present invention is shown;

[0026] Figure 8 A side view of an output pole base is shown according to an embodiment of the present invention.

[0027] Figure markings: 1-connector; 2-end plate; 201-first fixing hole; 202-second fixing hole; 3-module insulating member; 4-module buffer; 5-battery cell; 6-side plate; 7-insulating film; 8-middle plate; 801-third fixing hole; 802-positioning hole; 9-wiring harness assembly; 901-connector plug-in; 902-positioning column; 10-insulating strip; 11-output pole protective cover; 1101-snap buckle; 12-output pole base; 1201-block; 1202-connecting slot; S1-first direction; S2-second direction. DETAILED DESCRIPTION

[0028] To make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments. The components of the embodiments of the present application generally described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the application claimed for protection, but merely represents the selected embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without making creative work belong to the scope of protection of the present application.

[0029] In the description of the embodiments of the present application, it should be noted that the terms "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, or the positions or positional relationships in which the product of the application is usually placed when in use. They are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0030] In addition, the terms "horizontal", "vertical" and the like do not mean that the components are required to be absolutely horizontal or suspended, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0031] In the description of the embodiments of the present application, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "setting", "installation", "connection", and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal connection of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0032] According to a first aspect of the present invention, a battery module is provided. Figures 1 to 8 As shown, the battery module can cooperate with the box to form a part of the battery pack. The battery module includes an end plate 2, a side plate 6, a battery cell 5 and a module buffer 4.

[0033] In the following description, reference will be made to Figures 1 to 8 The detailed structures of the end plate 2, the side plate 6, the battery cell 5 and the module buffer 4 of the battery module are specifically described. In addition, in the description of the embodiment, two directions are also involved, namely the first direction S1 and the second direction S2. Since the battery module is formed into a substantially rectangular parallelepiped structure, the first direction S1 can be understood as the direction from one end to the other end of the rectangular parallelepiped structure in the length direction, and the second direction S2 can be understood as the direction from one end to the other end of the rectangular parallelepiped structure in the width direction.

[0034] like Figures 1 to 3As shown, in the embodiment, both ends of the battery module in the first direction S1 are provided with end plates 2, and both ends of the battery module in the second direction S2 are provided with side plates 6, and both the end plates 2 and the side plates 6 can play a protective role. The end plate 2 is connected to the side plate 6, preferably by welding. The welding connection method can produce a module with higher structural strength and improve the overall structural strength. The end plate 2 is provided with a first fixing hole 201 for connecting to the box body. The first fixing hole 201 of the end plate 2 can be connected to the box body by using a fastener. The fastener can be, for example, a fastening bolt or a connecting pin. This connection method can save the structural glue between the module and the box body, optimize the battery module assembly process, save assembly time, and avoid the problems of complicated processes, long time-consuming processes and low efficiency caused by the use of connecting glue in the original method. In addition, the use of fasteners can also preset the preload force in advance, which is simple in process and can improve accuracy. Further, the battery module may include a plurality of battery cells 5 and module buffers 4 arranged in sequence along the first direction S1, and a module buffer 4 is provided between two adjacent battery cells 5. The module buffer 4 may be, for example, a buffer pad, which may be made of a flexible material such as rubber, and the module buffer 4 provided between adjacent battery cells 5 can effectively alleviate the impact load of the expansion force generated during the battery cycle on the box body, so that the box body can always maintain the use strength and improve the service life.

[0035] In summary, the battery module improves the overall structural strength of the module by directly connecting the end plate 2 and the side plate 6, and uses the first fixing hole 201 to connect the end plate 2 and the box body, which can save the connecting glue between the battery module and the box body, optimize the assembly process, save assembly time, and can also preset the pre-tightening force in advance to ensure assembly accuracy; at the same time, a module buffer 4 is arranged between two adjacent battery cells 5 of the battery module, which can effectively reduce the impact load of the expansion force generated during the battery cycle on the box body.

[0036] Preferably, if Figure 1 , Figure 2 and Figure 5 As shown, in an embodiment, the battery module may further include a wiring harness assembly 9 located on the upper part of the battery cell 5, and the wiring harness assembly 9 may be, for example, a sampling connection harness, which can be welded to the battery cell 5 to achieve connection. The wiring harness assembly 9 is provided with a connector plug-in 901 at both ends in the first direction S1, and the end plate 2 is provided with a second fixing hole 202, and the connector plug-in 901 is connected to the end plate 2 through the second fixing hole 202. The second fixing hole 202 may be formed as, for example, a rivet hole, and the connector plug-in 901 may be fixedly connected to the second fixing hole 202 by using a connector 1, and the connector 1 may be, for example, an injection rivet. In this way, the end of the wiring harness assembly 9 may be fixedly connected to the end plate 2.

[0037] Preferably, if Figure 1 , Figure 2 and Figure 4 As shown, in the embodiment, the battery module may further include an intermediate plate 8, which is disposed in the middle of the plurality of battery cells 5 arranged along the first direction S1. Figure 2 In the embodiment, the plurality of cells 5 can respectively form a first cell group and a second cell group, and the first cell group and the second cell group are respectively arranged at the two ends of the middle plate 8 in the first direction S1. The middle plate 8 is provided with a third fixing hole 801 for connecting with the box body and a positioning hole 802 for positioning the wiring harness assembly 9. The third fixing hole 801 can be, for example, a screw hole or a pin hole, and the connection method between the third fixing hole 801 and the box body is the same as the connection method between the first fixing hole 201 and the box body, and fasteners can be used. The positioning hole 802 can be docked with the positioning column 902 described below to achieve the positioning and installation of the wiring harness assembly 9.

[0038] Preferably, if Figure 1 , Figure 2 , Figure 4 and Figure 5 As shown, in the embodiment, a positioning column 902 is provided in the middle of the wiring harness assembly 9, and the positioning column 902 is provided on the side of the wiring harness assembly 9 facing the battery cell 5. The positioning column 902 is provided corresponding to the positioning hole 802. In the embodiment, the number of the positioning holes 802 is two, and the number of the positioning columns 902 is also correspondingly two.

[0039] Preferably, in the embodiment, the wiring harness assembly 9 is welded to the battery core 5 .

[0040] Preferably, if Figure 1 and Figure 2 As shown, in the embodiment, both end faces of the middle plate 8 in the first direction S1 are provided with a module insulating member 3; a module insulating member 3 is provided between the battery cell 5 and the end plate 2. The module insulating member 3 can be used for insulation between the battery cell 5 and the end plate 2, and between the battery cell 5 and the middle plate 8.

[0041] Preferably, as 1 and Figure 2 As shown, in an embodiment, the battery module may further include an insulating strip 10 arranged on the upper part of the wiring harness assembly 9 and an insulating film 7 arranged on the lower part of the battery cell 5, the insulating strip 10 is provided with a connecting glue on the side facing the wiring harness assembly 9, and the insulating strip 10 is bonded to the wiring harness assembly 9; the insulating film 7 is provided with a connecting glue on the side facing the battery cell 5, and the insulating film 7 is bonded to the battery cell 5.

[0042] Preferably, as 1 and Figure 2As shown, in the embodiment, the module buffer 4 is bonded to the battery cell 5 by a connecting glue, and the connecting glue is arranged on two end faces of the module buffer 4 which are arranged back to back, and the two end faces which are back to back are respectively abutted against two adjacent battery cells 5, thereby realizing the connection between the module buffer 4 and the battery cell 5.

[0043] Preferably, as 1, Figure 2 , Figures 6 to 8 As shown, in the embodiment, one end of the wiring harness assembly 9 in the first direction S1 is also provided with an output pole protection cover 11 and an output pole base 12 that are clamped to each other. The top and bottom of the output pole base 12 are respectively provided with a clamping block 1201 and a connecting groove 1202. The output pole base 12 is arranged on the upper part of the end plate 2 through the connecting groove 1202. The end of the output pole protection cover 11 facing the output pole base 12 is provided with a clamping buckle 1101. The output pole protection cover 11 is clamped to the output pole base 12 through the cooperation of the clamping buckle 1101 and the clamping block 1201. The output pole base 12 can be fixed with the end plate 2 to ensure the stability and safety of the battery module. The output pole base 12 can realize the connection of the internal circuit of the battery module and ensure the normal flow of current. The output pole protection cover 11 can protect the output pole.

[0044] The battery module improves the overall structural strength of the module by directly connecting the end plate and the side plate, and uses the first fixing hole to connect the end plate and the box body, which can save the connecting glue between the battery module and the box body, optimize the assembly process, save assembly time, and can also preset the pre-tightening force in advance to ensure assembly accuracy; at the same time, a module buffer is provided between two adjacent battery cells of the battery module, which can effectively reduce the impact load on the box body caused by the expansion force generated during the battery cycle.

[0045] According to a second aspect of the present invention, a battery module assembly method is provided, which is applicable to the battery module as described above. The battery module assembly method comprises:

[0046] The first step is to test the appearance and electrical performance of the battery cell 5;

[0047] In the second step, the module buffer 4 enters the paper peeling station, the module buffer 4 is bonded to the end surface of the battery cell 5, and a module buffer 4 is arranged between adjacent battery cells 5;

[0048] In the third step, the plurality of cells 5 are respectively formed into a first cell group and a second cell group, an intermediate plate 8 is arranged between the first cell group and the second cell group, and the two end surfaces of the intermediate plate 8 facing the first cell group and the second cell group are both pasted with a module insulating member 3 with a single-sided adhesive backing;

[0049] Step 4: stack the first battery cell group, the second battery cell group, the middle plate 8, the side plate 6 and the end plate 2 in place, and use a fixture to fix the entire module to a set length;

[0050] Step 5: Apply structural adhesive to the side plate 6 to enhance the connection strength between the side of the battery module and the side plate 6;

[0051] Step 6: After the end plate 2 and the side plate 6 are installed and fixed, the end plate 2 and the side plate 6 are welded, and the weld is inspected and cleaned;

[0052] Step 7: snap the output pole base 12 onto the end plate 2;

[0053] Step 8: assemble the wiring harness assembly 9 to the middle plate 8, and snap the output pole protection cover 11 to the output pole base 12;

[0054] Step 9, welding the wiring harness assembly 9 to the first battery cell group and the second battery cell group, and performing weld inspection and cleaning;

[0055] In the tenth step, the insulating film 7 and the insulating strip 10 are bonded to the bottom and top of the battery module respectively.

[0056] The battery module assembly method can save the gluing process at the bottom of the box when the battery module is put into the box, optimize the assembly process, shorten the battery assembly time, and improve production efficiency.

[0057] In addition, according to a third aspect of the present invention, a battery pack is provided, wherein the battery pack comprises the battery module as described above. Since the battery pack uses the battery module as described above, the assembly time can be shortened and the production efficiency can be improved during the assembly process.

[0058] Finally, it should be noted that the above-described embodiments are only specific implementation methods of the present application, which are used to illustrate the technical solutions of the present application, rather than to limit them. The protection scope of the present application is not limited thereto. Although the present application is described in detail with reference to the above-described embodiments, ordinary technicians in the field should understand that any technician familiar with the technical field can still modify the technical solutions recorded in the above-described embodiments within the technical scope disclosed in the present application, or can easily think of changes, or make equivalent replacements for some of the technical features therein; and these modifications, changes or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application, and should be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. A battery module, which can be connected to a box of a battery pack, characterized in that: Both ends of the battery module in the first direction are provided with end plates, and both ends of the battery module in the second direction are provided with side plates, the end plates are connected to the side plates, and the end plates are provided with first fixing holes for connecting with the box body; The battery module comprises a plurality of battery cells and module buffers which are sequentially arranged along a first direction, and a module buffer is arranged between two adjacent battery cells.

2. The battery module according to claim 1, characterized in that: The battery module also includes a wiring harness assembly located on the upper part of the battery cell, and connector plugs are provided at both ends of the wiring harness assembly in the first direction. The end plate is provided with a second fixing hole, and the connector plug is connected to the end plate through the second fixing hole.

3. The battery module according to claim 2, characterized in that: The battery module also includes an intermediate plate, which is arranged in the middle of a plurality of battery cells arranged along the first direction, and is provided with a third fixing hole for connecting to the box body and a positioning hole for positioning the wiring harness assembly.

4. The battery module according to claim 3, characterized in that: A positioning column is provided in the middle of the wiring harness assembly, the positioning column is provided on a side of the wiring harness assembly facing the battery core, and the positioning column is provided corresponding to the positioning hole; The wiring harness assembly is welded to the battery core.

5. The battery module according to claim 3, characterized in that: The two end surfaces of the intermediate plate in the first direction are each provided with a module insulating member; A module insulating member is arranged between the battery core and the end plate.

6. The battery module according to claim 3, characterized in that: The battery module further comprises an insulating strip disposed on the upper part of the wiring harness assembly and an insulating film disposed on the lower part of the battery core, wherein a connecting glue is disposed on a side of the insulating strip facing the wiring harness assembly, and the insulating strip is bonded to the wiring harness assembly; A connecting glue is provided on a side of the insulating film facing the battery core, and the insulating film is bonded to the battery core.

7. The battery module according to claim 1, characterized in that: The module buffer is bonded to the battery cell by a connecting glue, and the connecting glue is arranged on two end surfaces of the module buffer that are arranged opposite to each other, and the two end surfaces that are arranged opposite to each other are respectively in contact with two adjacent battery cells.

8. The battery module according to claim 2, characterized in that: The wiring harness assembly is also provided with an output pole protection cover and an output pole base that are clamped to each other at one end in the first direction; The top and bottom of the output pole base are respectively provided with a card block and a connecting groove, and the output pole base is arranged on the end plate through the connecting groove. The end of the output pole protection cover facing the output pole base is provided with a snap buckle, and the output pole protection cover is snapped to the output pole base through the cooperation of the snap buckle and the card block.

9. A battery pack, characterized in that: The battery pack comprises the battery module according to any one of claims 1 to 8.

10. A battery module assembly method, characterized in that: The battery module assembly method comprises: Conduct appearance and electrical performance inspection on the battery cells; The module buffer enters the paper peeling station, the module buffer is bonded to the end surface of the battery cell, and one module buffer is arranged between adjacent battery cells; The plurality of battery cells respectively form a first battery cell group and a second battery cell group, an intermediate plate is arranged between the first battery cell group and the second battery cell group, and two end surfaces of the intermediate plate facing the first battery cell group and the second battery cell group are both pasted with a module insulating member with a single-sided adhesive backing; Stack the first battery cell group, the second battery cell group, the middle plate, the side plate and the end plate in place, and use a fixture to fix the module to a set length; Apply structural adhesive to the side panels to improve the connection strength between the sides of the battery module and the side panels; After the end plates and side plates are installed and fixed, they are welded and the welds are inspected and cleaned; Attach the output pole base to the end plate; Assemble the wiring harness assembly to the middle plate, and snap the output pole protection cover to the output pole base; Welding the wiring harness assembly to the first battery cell group and the second battery cell group, and performing weld inspection and cleaning; The insulating film and the insulating strip are respectively bonded to the bottom and the top of the battery module.

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