A battery module

Abstract

The present invention specifically relates to a battery module, comprising: battery cells, which are arranged in a front-back direction of the battery module to form a battery cell group; end plates, located at the front and back ends of the battery cell group in the front-back direction; a heating film, having a side-attached portion and a bent portion, the bent portion being connected to the end of the side-attached portion, and the bent portion being configured to bend towards the end face of the end plate; the heating film further includes a wire outlet position located at the bent portion; the end plate is provided with fixing holes, and the heating film is provided with cable tie perforations, and the heating film is fixed to the end plate by a cable tie passing through the fixing holes and the cable tie perforations, and the cable tie presses the bent portion towards the end face of the end plate; a groove is provided on the end edge of the bent portion, and the groove is located between the wire outlet position and the cable tie perforation adjacent to the wire outlet position in the up-down direction, and is used to isolate the area on the bent portion that is subjected to the crimping action of the cable tie from the area provided with the wire outlet position. The present invention can not only reduce the damage and cracking of the heating film caused by pulling the wire outlet position, but also reduce the shearing force of the cable tie on the heating film.

Description

Technical Field

[0001] The present invention belongs to the technical field of batteries, and particularly relates to a battery module. Background Art

[0002] There is an inseparable connection between the charge and discharge rate of the battery module and the temperature. In a relatively cold environment, the working performance and life of the battery module will be greatly reduced, and even safety problems will be brought. Therefore, a stable and intact heating device needs to be installed on the battery module, such as adding an electrothermal film to the battery module.

[0003] Currently, the vast majority of the connection methods between the electrothermal film and the battery module adopt the connection method of bonding + mechanical fixing, that is, the entire electrothermal film is first fixed on the battery module by bonding, and then the fixing effect of the heating film is further strengthened by mechanical fixing on the basis of bonding. The heating film includes a side attachment part, and the side attachment part is used to contact the side of the battery module. Since there are tolerances in the assembly of the heating film and the battery module, the length of the electrothermal film is longer than the length of the battery module, and the part of the electrothermal film that extends beyond the battery module constitutes a bent part. When installing the heating film, the bent part needs to be bent inward to the battery module and fixed on the end face of the battery module. The electrothermal film also includes a wire outlet position and a fixing position. The wire outlet position is located at the bent part, and the wire outlet position is used to connect to the power supply circuit. The fixing position is used for mechanical fixing. Generally, mechanical fixing is achieved by tightening a cable tie, and the bent part can be further pressed and fixed on the battery module by tightening the cable tie.

[0004] However, due to the phenomenon of thermal expansion and contraction of the battery cells in the battery module and the relatively complex operating conditions of the battery module, the battery module is prone to de-bonding after being used for a period of time. Especially after the bent part is de-bonded, a rebound phenomenon will occur. In this way, the cable tie will be affected by the rebound of the entire bent part, making the shear stress on both sides of the tightened cable tie become larger, that is, it will exacerbate the shear of the cable tie on the bent part, resulting in cracking and damage of the electrothermal film. Summary of the Invention

[0005] The purpose of the present invention is to provide a battery module to solve the problem of cracking and damage of the heating film caused by the cable tie being affected by the rebound of the entire bent part in the prior art.

[0006] The battery module in the present invention adopts the following technical solutions:

[0007] The battery module includes:

[0008] Battery cells are arranged in the front-back direction of the battery module to form a battery cell group;

[0009] End plates are located at the front and rear ends of the battery cell group in the front-back direction;

[0010] The electrothermal film has a side-attached part and a bent part. The side-attached part is used to contact the side of the battery cell group, and the bent part is connected to the end of the side-attached part and is used to bend towards the end face of the end plate. An outgoing wire position is provided at the end edge of the bent part, and the outgoing wire position is used to connect to the power supply circuit.

[0011] Fixing holes are provided on the horizontal side of the end plate. Tie holes are provided on the electrothermal film, and the tie holes are located laterally on the side of the outgoing wire position in the up-down direction. The electrothermal film is fixed to the end plate by a tie that passes through both the fixing holes and the tie holes at the same time, and the tie presses the bent part of the electrothermal film towards the end face of the end plate.

[0012] A groove is provided on the end edge of the bent part, and the groove is located between the outgoing wire position and the tie hole adjacent to the outgoing wire position in the up-down direction, and is used to isolate the area on the bent part that is subjected to the crimping action of the tie from the area where the outgoing wire position is provided.

[0013] The beneficial effects of the above technical solution are as follows: In the present invention, a groove is provided on the end edge of the bent part, and the groove is provided between the outgoing wire position and the tie hole adjacent to the outgoing wire position, so that the area on the bent part that is subjected to the crimping action of the tie can be isolated from the outgoing wire position area. This can not only reduce the damage and cracking of the electrothermal film caused by pulling when the outgoing wire position is connected to the power supply circuit, but also reduce the area on the bent part where the tie is subjected to the rebound action. Compared with the tie being subjected to the rebound action of the entire bent part, this reduces the rebound action of the bent part on the tie, that is, reduces the shearing force of the tie on the electrothermal film, and thus relatively avoids the damage and cracking of the electrothermal film caused by the shearing of the tie, and prolongs the service life of the electrothermal film.

[0014] Further, the groove is U-shaped.

[0015] The beneficial effects of the above technical solution are as follows: Setting the groove to be U-shaped makes the bottom of the groove in a smooth transition state, which can reduce the stress concentration at the bottom of the groove, that is, can relatively reduce the damage and cracking of the electrothermal film when the outgoing wire position is pulled.

[0016] Further, the bottom part of the groove is in the shape of a superior arc, so that the groove forms a closed structure.

[0017] The beneficial effects of the above technical solution are as follows: On the basis of ensuring that the groove can separate the outgoing wire position from the tie fixing position, by setting the bottom part of the groove to be in the shape of a superior arc, the area where the tie is subjected to the rebound action can be further reduced, that is, the rebound action on the tie is further reduced, and the shearing force of the tie on the electrothermal film is also further reduced.

[0018] Further, the electrothermal film further includes a lead-out part protruding from the edge of the bent part, and the lead-out part constitutes the outgoing wire position.

[0019] The beneficial effects of the above technical solution are as follows: An extraction part is provided at the edge of the bent part, and the extraction part is used as the wire outlet position. In this way, the pulling force when the wire outlet position is connected to the power supply circuit can be relatively reduced, that is, the damage and cracking of the electrothermal film can be relatively reduced.

[0020] Further, the groove wall of the groove close to the extraction part and the corresponding side of the extraction part are on the same straight line.

[0021] The beneficial effects of the above technical solution are as follows: In this way, the extraction part and other areas of the bent part are just separated, and the damage and cracking caused by pulling on the connection between the extraction part and the bent part when the extraction part is connected to the power supply circuit can be relatively reduced, that is, the protection effect on the connection between the extraction part and the bent part is better.

[0022] Further, the groove wall of the groove close to the extraction part and the corresponding side of the extraction part are arranged at intervals.

[0023] The beneficial effects of the above technical solution are as follows: In this way, the area where the cable tie is subjected to the rebounding effect becomes smaller, that is, the rebounding effect of the bent part on the cable tie also becomes smaller, which is more conducive to avoiding the cracking and damage of the electrothermal film.

[0024] Further, an arc transition is formed between the end edge of the bent part and the corresponding side of the extraction part.

[0025] The beneficial effects of the above technical solution are as follows: In this way, the strength of the transition section between the end edge of the bent part and the corresponding side of the extraction part can be enhanced through the arc structure, which is beneficial to avoiding the damage and cracking of the transition section caused by the pulling of the extraction part.

[0026] Further, the cable tie perforation is located inside the electrothermal film relative to the groove.

[0027] The beneficial effects of the above technical solution are as follows: By arranging the cable tie perforation inside the electrothermal film relative to the groove, it is convenient for the cable tie to pass through the cable tie perforation and the fixing hole on the horizontal side of the end plate, that is, it is convenient for the cable tie to be tightened and fixed, making the fixing effect of the cable tie on the electrothermal film better.

[0028] Further, the wire outlet position is located in the middle of the bent part, and the cable tie perforations are provided on both the upper and lower sides of the wire outlet position.

[0029] The beneficial effects of the above technical solution are as follows: The wire outlet position is set in the middle of the bent part, and tie-tape perforations are provided on both sides in the up-and-down direction of the wire outlet position. This can make the fixing effect of the tie-tape on the electric heating film better, and at the same time can relatively reduce the area where a single tie-tape is affected by the rebound effect, that is, it can relatively reduce the shearing of the electric heating film by a single tie-tape, which is more conducive to avoiding the cracking and damage of the electric heating film.

[0030] Further, the bent part is fixedly bonded to the end face of the end plate.

[0031] The beneficial effects of the above technical solution are as follows: This can not only strengthen the fixing effect of the electric heating film, but also reduce the rebound effect of the bent part on the tie-tape through the bonding between the bent part and the end face of the end plate, which is more conducive to avoiding the cracking and damage of the electric heating film. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 is a partial schematic view of the battery module in the present invention;

[0033] Figure 2 is a schematic view of the groove in Embodiment 1 of the present invention;

[0034] Figure 3 is a schematic view of the groove in Embodiment 2 of the present invention;

[0035] Figure 4 is a schematic view of the groove in Embodiment 3 of the present invention.

[0036] In the figure: 1, battery cell; 2, end plate; 2-1, fixing hole; 3, electric heating film; 3-1, side attachment part; 3-2, groove; 3-3, tie-tape perforation; 3-4, bent part; 3-4-1, wire outlet position; 4, tie-tape; 5, power connection wire. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0037] In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention, that is, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Usually, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0038] Therefore, the detailed description of the embodiments of the present invention provided in the drawings below is not intended to limit the scope of the claimed present invention, but merely represents the selected embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative efforts belong to the scope of protection of the present invention.

[0039] It should be noted that in the specific embodiments of the present invention, relative terms such as "first" and "second" that may appear are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, terms such as "comprising", "including" or any other variants thereof that may appear are intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements not only includes those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. Without further limitation, the elements defined by the statement "comprising one..." etc. do not exclude the existence of additional identical elements in the process, method, article or device comprising the said elements.

[0040] In the description of the present invention, unless otherwise clearly defined and limited, relative terms such as "installed", "connected" and "coupled" 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 an indirect connection through an intermediate medium, or it can be the communication inside two components. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood through specific situations.

[0041] In the description of the present invention, unless otherwise clearly defined and limited, the relative term "provided with" should be understood in a broad sense. For example, the object of "provided with" can be a part of the body, or can be arranged separately from the body and connected to the body, and this connection can be a detachable connection or a non-detachable connection. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood through specific situations.

[0042] The following further describes the present invention in detail with reference to embodiments.

[0043] Embodiment 1 of the battery module in the present invention:

[0044] As Figure 1 shown, the battery module includes battery cells 1 and end plates 2. Among them, a plurality of battery cells 1 are arranged in the front-back direction of the battery module, and the plurality of battery cells 1 form a battery cell group; the end plates 2 are located at the ends of the battery cell group in the front-back direction, and fixing holes 2-1 are provided on the side surfaces of the end plates 2 in the horizontal direction.

[0045] As Figure 1As shown, the battery module further includes a heating film 3, which has a side-attached portion 3-1 and a bent portion 3-4. Among them, the side-attached portion 3-1 is used to contact the side surface of the battery cell group, and the side-attached portion 3-1 is fixedly connected to the side surface of the battery cell group by bonding; the bent portion 3-4 is connected to the end of the side-attached portion 3-1, and the bent portion 3-4 is used to bend towards the end face of the end plate 2, and the bent portion 3-4 is also fixedly connected to the end face of the end plate 2 by bonding.

[0046] As Figure 1 and Figure 2 shown, an outgoing line position 3-4-1 is provided at the end edge of the bent portion 3-4. The outgoing line position 3-4-1 is located in the middle of the bent portion 3-4. A power connection line 5 is led out from the outgoing line position 3-4-1 to be connected to a power supply circuit, that is, the outgoing line position 3-4-1 is used to connect to the power supply circuit. The heating film 3 further includes a lead-out portion protruding from the edge of the bent portion 3-4, and the lead-out portion constitutes the outgoing line position 3-4-1, that is, the outgoing line position 3-4-1 extends outward relative to the end edge of the bent portion 3-4.

[0047] As Figure 1 and Figure 2 shown, a tie-rod perforation 3-3 is provided on the heating film 3. The tie-rod perforation 3-3 is located on both sides of the outgoing line position 3-4-1 in the up-down direction. The heating film 3 is fixed to the end plate 2 by a tie-rod 4 passing through the fixing hole 2-1 and the tie-rod perforation 3-3 at the same time. And on the basis that the bent portion 3-4 is fixedly bonded to the end face of the end plate 2, the tie-rod 4 further presses the bent portion 3-4 towards the end face of the end plate 2, that is, further fixes the heating film 3 to prevent the heating film 3 from detaching from the battery cell group after the glue comes off, thereby causing dry burning of the heating film 3 and triggering a safety accident.

[0048] As Figure 1 and Figure 2 shown, a groove 3-2 is provided on the end edge of the bent portion 3-4. The groove 3-2 is located between the outgoing line position 3-4-1 and the tie-rod perforation 3-3 adjacent to the outgoing line position 3-4-1 in the up-down direction, and is used to isolate the area on the bent portion 3-4 that is subjected to the pressing action of the tie-rod 4 from the area where the outgoing line position 3-4-1 is provided. The bottom part of the groove 3-2 is in the shape of a superior arc, so that the groove 3-2 forms a closed structure. The groove wall of the groove 3-2 close to the outgoing line position 3-4-1 and the corresponding side edge of the outgoing line position 3-4-1 are on the same straight line, and the tie-rod perforation 3-3 is located inside the heating film 3 relative to the groove 3-2.

[0049] In the present invention, by providing a groove on the end edge of the bent portion and arranging the groove between the wire outlet position and the cable tie perforation adjacent to the wire outlet position, the area on the bent portion that is subjected to the crimping action of the cable tie can be isolated from the wire outlet position area. This can not only reduce the damage and cracking of the electrothermal film caused by pulling when connecting the power supply circuit at the wire outlet position, but also, when the bent portion becomes de-bonded, reduce the area where the cable tie is subjected to the spring-back action in the bent portion. Compared with the cable tie being subjected to the spring-back action of the entire bent portion, this reduces the spring-back action of the bent portion on the cable tie, that is, reduces the shearing force of the cable tie on the electrothermal film. Therefore, relatively, the damage and cracking of the electrothermal film caused by the shearing of the cable tie are avoided, and the service life of the electrothermal film is extended.

[0050] Example 2 of the battery module in the present invention:

[0051] The difference between this embodiment and Embodiment 1 is that, in Embodiment 1, the bottom part of the groove 3-2 has a shape of a superior arc, such that the groove 3-2 forms a closed structure, while in this embodiment, as Figure 3 shown, the groove 3-2 is U-shaped.

[0052] Example 3 of the battery module in the present invention:

[0053] The difference between this embodiment and Embodiment 1 is that, in Embodiment 1, the groove wall of the groove 3-2 close to the wire outlet position 3-4-1 and the corresponding side of the wire outlet position 3-4-1 are on the same straight line, while in this embodiment, as Figure 4 shown, the groove wall of the groove 3-2 close to the wire outlet position 3-4-1 and the corresponding side of the wire outlet position 3-4-1 are arranged at intervals, and there is an arc transition between the end edge of the bent portion 3-4 and the corresponding side of the wire outlet position 3-4-1.

[0054] Example 4 of the battery module in the present invention:

[0055] The difference between this embodiment and Embodiment 1 is that, in Embodiment 1, the cable tie perforation 3-3 is located inside the electrothermal film 3 relative to the groove 3-2, while in this embodiment, the cable tie perforation 3-3 is arranged close to the end edge of the bent portion.

[0056] Example 5 of the battery module in the present invention:

[0057] The difference between this embodiment and Embodiment 1 is that, in Embodiment 1, the wire outlet position 3-4-1 is composed of the leading-out part protruding from the edge of the bent portion 3-4, while in this embodiment, the end edge of the wire outlet position 3-4-1 is flush with the end edge of the bent portion.

[0058] Example 6 of the battery module in the present invention:

[0059] The difference between this embodiment and Embodiment 1 is that in Embodiment 1, the electrothermal film 3 is fixed by means of bonding and cable ties 4, while in this embodiment, the electrothermal film 3 is fixed only by means of cable ties 4.

[0060] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. The patent protection scope of the present invention is subject to the claims. All equivalent structural changes made by using the content of the specification and drawings of the present invention should, by the same token, be included in the protection scope of the present invention.

Claims

1. A battery module, comprising: electric cores (1) arranged in the front - rear direction of the battery module to form a group of electric cores; end plates (2) located at the front - rear ends of the group of electric cores; a heating film (3) having a side - attached portion (3 - 1) and a bent portion (3 - 4), the side - attached portion (3 - 1) being used to contact the side surface of the group of electric cores, the bent portion (3 - 4) being connected to the end of the side - attached portion (3 - 1) and being used to bend towards the end face of the end plate (2); an outgoing line position (3 - 4 - 1) is provided at the end edge of the bent portion (3 - 4), and the outgoing line position (3 - 4 - 1) is used to connect to a power supply circuit; fixing holes (2 - 1) are provided on the lateral side of the end plate (2) in the horizontal direction, a tie - strap perforation (3 - 3) is provided on the heating film (3), and the tie - strap perforation (3 - 3) is located laterally of the outgoing line position (3 - 4 - 1) in the up - down direction; the heating film (3) is fixed to the end plate (2) by a tie - strap (4) passing through both the fixing hole (2 - 1) and the tie - strap perforation (3 - 3) simultaneously, and the tie - strap (4) presses the bent portion (3 - 4) of the heating film (3) towards the end face of the end plate (2); characterized in that a groove (3 - 2) is provided on the end edge of the bent portion (3 - 4), the groove (3 - 2) is located between the outgoing line position (3 - 4 - 1) and the tie - strap perforation (3 - 3) adjacent to the outgoing line position (3 - 4 - 1) in the up - down direction, and is used to isolate the area on the bent portion (3 - 4) subjected to the pressing action of the tie - strap (4) from the area provided with the outgoing line position (3 - 4 - 1).

2. The battery module according to claim 1, characterized in that the groove (3 - 2) is U - shaped.

3. The battery module according to claim 1, characterized in that the bottom part of the groove (3 - 2) is in the shape of a superior arc, so that the groove (3 - 2) forms a closed - mouth structure.

4. The battery module according to any one of claims 1 to 3, characterized in that the heating film (3) further includes a lead - out portion protruding from the edge of the bent portion (3 - 4), and the lead - out portion constitutes the outgoing line position (3 - 4 - 1).

5. The battery module according to claim 4, characterized in that the groove wall of the groove (3 - 2) close to the lead - out portion and the corresponding side edge of the lead - out portion are on the same straight line.

6. The battery module according to claim 4, characterized in that the groove wall of the groove (3 - 2) close to the lead - out portion and the corresponding side edge of the lead - out portion are arranged at intervals.

7. The battery module according to claim 6, characterized in that an arc - shaped transition is formed between the end edge of the bent portion (3 - 4) and the corresponding side edge of the lead - out portion.

8. The battery module according to any one of claims 1 to 3, characterized in that the tie - strap perforation (3 - 3) is located inside the heating film (3) relative to the groove (3 - 2).

9. The battery module according to any one of claims 1 to 3, characterized in that the outgoing line position (3 - 4 - 1) is located in the middle of the bent portion (3 - 4), and tie - strap perforations (3 - 3) are provided on both the upper and lower sides of the outgoing line position (3 - 4 - 1) in the up - down direction.

10. The battery module according to any one of claims 1 to 3, characterized in that, the bent portion (3-4) is fixedly bonded to the end face of the end plate (2).

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