CN110197937B

CN110197937B - Heating film system assembly for battery pack

Info

Publication number: CN110197937B
Application number: CN201910619572.0A
Authority: CN
Inventors: 李金鹏; 刘心文; 吴贵新; 赵明; 刘艳
Original assignee: FJ Motor Group Yudo New Energy Automobile Co Ltd
Current assignee: FJ Motor Group Yudo New Energy Automobile Co Ltd
Priority date: 2019-07-10
Filing date: 2019-07-10
Publication date: 2022-02-22
Anticipated expiration: 2039-07-10
Also published as: CN110197937A

Abstract

The invention relates to the technical field of battery packs for electric automobiles, in particular to a heating film system assembly for a battery pack, which comprises a PI heating film body and isolating foam, wherein the PI heating film body comprises a PI film and a resistance wire, a hollowed hole is formed in the PI film, the PI film is divided into at least two module layout areas by the hollowed hole, adjacent module layout areas are connected through the PI films on two sides of the hollowed hole, the resistance wire is coated in the module layout areas, the resistance wires between the adjacent module layout areas are arranged in series, the opening position of the hollowed hole is not overlapped with the layout area of the resistance wire, and the isolating foam is respectively arranged on the PI films on two sides of the hollowed hole. Electric connection is more succinct reliable in this scheme, simultaneously based on the compliance of PI membrane for it can carry out self-adaptation adjustment according to PI heating membrane body mounted position contact surface curved surface characteristic, and the commonality is strong, and has alleviateed the weight of PI heating membrane system assembly greatly, is favorable to the lightweight design of battery package.

Description

Heating film system assembly for battery pack

Technical Field

The invention relates to the technical field of battery packs for electric vehicles, in particular to a heating film system assembly for a battery pack.

Background

The design of the lithium battery pack of the current electric automobile increasingly emphasizes the design of high specific energy. The same is true for thermal management system components. The main design mode of the current thermal management system is air cooling or liquid cooling; when heating at low temperature, the air-cooled battery pack generally adopts integrated PTC to blow internal thermal circulation air to realize the heating function; the liquid cooling realizes the heating function by heating the refrigerating fluid through the PTC of the front cabin; for a natural battery pack, a heating film with a resistance wire is generally required to be adopted, and an integral epoxy plate integrated resistance wire heating film scheme and an aluminum vapor chamber integrated PTC resistance wire scheme are common in the existing heating film integration scheme.

The above schemes all have the following disadvantages: first, no matter be the integrated resistance wire heating film of integral epoxy board or the integrated PTC resistance wire heating film of aluminium soaking plate, whole weight is overweight, does not adapt to present increasingly strict lightweight demand. Second, the main part all is hard material, and the difficult abundant contact of guaranteeing of the cooperation of the electric core bottom surface of heating film and module bottom stereoplasm, so need cooperate the heat conduction silica gel pad to use in the actual use, further increaseed system weight, also increased system cost. Third, for guaranteeing to fully contact with module electricity core bottom surface, often need apply certain compression in the in-service engineering use, and heat conduction silica gel pad is difficult compression material, need support the rebound material and provide great resilience force, has further increaseed the cost of supporting thermal insulation material between heating film and the battery package casing.

Disclosure of Invention

Therefore, a heating film system assembly for a battery pack is needed to be provided to solve the problems of heavy weight and high use cost of the existing heating film assembly for the battery pack.

In order to achieve the purpose, the inventor provides a heating film system assembly for a battery pack, the heating film system assembly comprises a PI heating film body and isolation foam, the PI heating film body comprises a PI film and a resistance wire, hollow holes are formed in the PI film, the PI film is separated into at least two modules through the hollow holes to be arranged in the regions, adjacent modules are connected through PI films on two sides of the hollow holes, the resistance wire is coated inside the modules in the region, the resistance wire between the adjacent modules is arranged in series, the arrangement positions of the hollow holes are not overlapped with the arrangement regions of the resistance wire, and the isolation foam is respectively arranged on the PI films on two sides of the hollow holes.

As a preferable structure of the present invention, the heating film system assembly further includes a bottom support foam, and the PI heating film body is disposed on the bottom support foam.

As a preferable structure of the invention, the bottom supporting foam is combined foam which is formed by combining silica gel foam and microporous foamed polypropylene.

As a preferred structure of the invention, the bottom support foam is located below the module layout region, and the shape and size of the bottom support foam are matched with the overall dimension of the PI film in the module layout region.

As a preferable structure of the present invention, both sides of the upper surface of the bottom support foam are provided with adhesive backsizes.

As a preferable structure of the invention, two sides of the lower surface of the bottom supporting foam are provided with adhesive back glue.

As a preferred structure of the present invention, the PI film in the PI heating film body is formed by hollow punching.

As a preferable structure of the present invention, the PI film in the module layout region has a square structure.

As a preferable structure of the invention, the heating film system assembly further comprises wire outgoing ends with plug-ins, and the wire outgoing ends with plug-ins are respectively arranged at two ends of the PI heating film body and are communicated with the resistance wires arranged in series.

As a preferable structure of the invention, the heating film system assembly further comprises a wire outlet end isolation foam, and the wire outlet end isolation foam is wrapped at the connection part of the wire outlet end with the plug-in component and the resistance wire.

Different from the prior art, the technical scheme has the following advantages: the invention relates to a heating film system assembly for a battery pack, wherein a PI heating film body comprises a PI film and a resistance wire, a hollow hole is formed in the PI film to divide the PI film into at least two adjacent module arrangement areas, the resistance wire is coated in the module arrangement areas, the resistance wires between the adjacent module arrangement areas are connected in series, and the resistance wire is electrified to generate heat so as to heat a heat-conducting medium and a heat-conducting surface of a battery module, so that the battery module arranged on the PI heating film body is heated at low temperature. According to the invention, the PI (polyimide) heating film is adopted, and the PI heating film body is subjected to integral series-connection type hollow design, so that the connecting joints among the traditional heating films and the circuit arrangement of wire transfer are reduced, the electrical connection is more concise and reliable, meanwhile, based on the flexibility of the PI film, the PI heating film can be subjected to self-adaptive adjustment according to the curved surface characteristic of the contact surface of the installation position of the PI heating film body, the universality is strong, the weight of the PI heating film system assembly is greatly reduced, and the lightweight design of a battery pack is facilitated.

Drawings

FIG. 1 is a schematic perspective view of a heating film system assembly for a battery pack according to an embodiment;

FIG. 2 is an exploded view of one embodiment of a heating film system assembly for a battery pack according to the present invention;

FIG. 3 is a schematic perspective view of an embodiment of a PI heating film body in the heating film system assembly for a battery pack;

FIG. 4 is one of the schematic perspective views of an embodiment of a bottom support foam in the heating film system assembly for a battery pack according to the present embodiment;

FIG. 5 is a second schematic perspective view of an embodiment of a bottom support foam in a heating film system assembly for a battery pack according to the embodiments;

FIG. 6 is a schematic front view of a portion of an embodiment of a heating film system assembly for a battery pack according to an embodiment;

FIG. 7 is a schematic front view of a portion of a battery pack heating film system assembly according to an embodiment in combination with a battery module;

fig. 8 is a schematic perspective view of an embodiment of resistance wires in a heating film system assembly for a battery pack according to an embodiment.

Description of reference numerals:

100. PI heating the membrane body;

110. a PI film; 111. hollowing out holes;

120. a resistance wire;

130. a module arrangement region;

200. isolating foam;

300. bottom support foam;

400. bonding gum;

500. a wire outlet end with a plug-in;

600. the outlet end is isolated by foam;

700. a battery module is provided.

Detailed Description

To explain technical contents, structural features, and objects and effects of the technical solutions in detail, the following detailed description is given with reference to the accompanying drawings in conjunction with the embodiments.

Referring to fig. 1 to 8, the present invention provides a heating film system assembly for a battery pack, which is used for heating a heat-conducting medium through a heating film when a thermal management system of the battery pack is in a low-temperature environment, so as to achieve a function of heating a battery module 700. Specifically, the heating film system assembly comprises a PI heating film body 100 and isolating foam 200, the PI heating film body 100 comprises a PI film 110 and a resistance wire 120, a hollow hole 111 is formed in the PI film 110, the PI film 110 is divided into at least two module layout areas 130 through the hollow hole 111, adjacent module layout areas 130 are connected through the PI films 110 on two sides of the hollow hole 111, the resistance wire 120 is coated inside the module layout areas 130, the resistance wires 120 between the adjacent module layout areas 130 are arranged in series, the opening positions of the hollow holes 111 are not overlapped with the layout areas of the resistance wire 120, and the isolating foam 200 is respectively arranged on the PI films 110 on two sides of the hollow hole 111.

The PI heating film body 100 is a main body member for heating the battery module 700. Specifically, the PI heating membrane body 100 includes a PI membrane 110 and a resistance wire 120, the PI membrane 110 is also called a polyimide membrane, and the polyimide membrane (polyimide film) is a film-type insulating material with the best performance in the world, and includes a pyromellitic polyimide membrane and a biphenyl polyimide membrane. The PI film 110 has excellent heat resistance, excellent mechanical properties, i.e., high tensile strength, good flexibility, good chemical stability and resistance to moist heat, good radiation resistance, and good insulating properties. The resistance wire 120 can emit a large amount of heat after being electrified so as to heat the heat-conducting medium, and effective battery pack heat management is realized. The foam is a material foamed by plastic particles, and is called foam for short. The foam has a series of excellent characteristics of good elasticity, light weight, quick pressure-sensitive fixation, convenient use, free bending, ultrathin volume, reliable performance and the like.

As shown in fig. 3, the PI film 110 is provided with a hollow hole 111 to divide the PI film 110 into at least two module layout regions 130, and the hollow hole 111 is designed to facilitate heat dissipation after the resistance wire 120 is powered on, so that the heating effect on the battery module 700 is better, and the PI film more conforms to the structural design of the battery module 700, so that the material consumption of the PI film 110 can be saved, and the cost can be saved. Referring to fig. 3 and 8, the adjacent module layout regions 130 are connected by the PI films 110 on both sides of the hollow hole 111, and the resistance wires 120 between the adjacent module layout regions 130 are arranged in series, so that the resistance wires 120 are routed through the PI films 110 at the connection between the two adjacent module layout regions 130, thereby reducing the connection joints between the conventional heating films and the circuit arrangement of wire transfer, and making the electrical connection more concise and reliable. And the heating film of the Polyimide (PI) packaging substrate is adopted to replace the traditional scheme of the epoxy plate and the aluminum soaking plate integrated resistance wire 120, so that the weight of the heating film body is greatly reduced, and the lightweight design of the heating film and the battery pack is facilitated. Specifically, as shown in fig. 1 and 3, 5 hollow holes 111 are formed in the PI film 110, and 6 module layout regions 130 are formed in the PI film 110. In addition, the isolation foam 200 is arranged on the PI film 110 on two sides of the hollow hole 111, that is, the isolation foam 200 is arranged on the top of the PI heating film body 100, and the compression and downward pushing functions of the isolation foam 200 enable the battery module 700 to be in contact with the PI film 110 and prevent the peripheral part of the battery module from being worn due to vibration after the battery module 700 is installed, and the isolation foam 200 can be fixed with the PI film 110 in a self-positioning mode, so that an additional positioning tool is not needed, and the production process is simplified.

The heating film system assembly for the battery pack comprises a PI film body 100, a PI film 110 and a resistance wire 120, wherein the PI film 110 is provided with a hollow hole 111 to divide the PI film 110 into at least two modules to be arranged in an area 130, the resistance wire 120 is wrapped in the module arranged in the area 130, the resistance wires 120 between the adjacent modules in the area 130 are arranged in series, the resistance wire 120 is electrified to generate heat to heat a heat-conducting medium and a heat-conducting surface of a battery module 700, and the battery module 700 arranged on the PI heating film body 100 is further heated at low temperature. In the invention, the PI (polyimide) heating film is adopted, and the PI heating film body 100 is designed to be integrally connected in series in a hollow manner, so that the connecting joints among the traditional heating films and the circuit arrangement for wire switching are reduced, the electrical connection is more concise and reliable, meanwhile, based on the flexibility of the PI film 110, the PI heating film can be adaptively adjusted according to the curved surface characteristic of the contact surface of the installation position of the PI heating film body 100, the universality is strong, the weight of the PI heating film system assembly is greatly reduced, the lightweight design of a battery pack is facilitated, and the high specific energy design with advanced technology is achieved.

Referring to fig. 1, 2, 6 and 7, as a preferred embodiment of the present invention, the heating membrane system assembly further includes a bottom supporting foam 300, and the PI heating membrane body 100 is disposed on the bottom supporting foam 300. Preferably, the heating film is designed by embedding the resistance wire 120 into the PI film 110, and the PI film 110 is light and can be tightly attached to the heat-conducting surface at the bottom of the battery module 700, so that the requirement on the mechanical support performance of the PI film 110 on the bottom is greatly reduced, the requirement on the material compression amount and the compression rebound strength of the bottom support rebound structure is greatly reduced, and the weight and the production cost of the bottom support component are also reduced. Specifically, the bottom support foam 300 has a compression rebound jacking function, and when the bottom support foam is matched with the compression lower jacking function of the top isolation foam 200, the battery module 700 can be in full contact with the PI film 110 and isolated from the peripheral elements of the battery module 700, and efficient heat transfer with the battery module can be realized without additional heat-conducting silica gel pads, heat-conducting grease and other materials; saving material costs while preventing the battery module 700 or peripheral components from being worn. And the bottom supporting foam 300 can realize self-positioning with the PI die, so that an additional positioning tool is not needed, the production process is simplified, the production efficiency is improved, the production cost is reduced, and the production line type production line is particularly suitable for production line type production.

As shown in fig. 1, 2, 4 and 5, as a preferred embodiment of the present invention, the bottom support foam 300 is a combination foam which is a combination of a silicone foam and a micro-porous foamed polypropylene (MPP). In the long-term actual use and theoretical calculation process, it is found that the bottom support foam 300 is a combined foam formed by combining silica gel foam and microporous foamed polypropylene (MPP), and can be matched with the top isolation foam 200, so that the battery module 700 is in full contact with the PI film 110, the abrasion of the PI film 110 and peripheral parts is avoided, and the use effect is good. The bottom support foam 300 adopts a combined form of silica gel foam and microporous foamed polypropylene (MPP) in a matching design, so that the compression resilience performance in the service life of the whole vehicle quality guarantee is ensured while the usage amount of high-cost silica gel materials is reduced, and the production and use cost is favorably saved. It should be noted that the combined foam is only a structural product composed of the silica gel foam and the microporous foamed polypropylene (MPP) material, and does not relate to the combination of the chemical components of the silica gel foam and the MPP material. As shown in fig. 6, the upper layer of silica gel foam and the lower layer of microporous foamed polypropylene (MPP) are layered up and down. For example, the bottom support foam 300 is formed by stacking an upper layer of silicone foam and a lower layer of microporous foamed polypropylene (MPP), and the two layers are designed to match the respective thicknesses according to the requirements of the support and heat insulation performance.

Referring to fig. 1 and 2, as a preferred embodiment of the present invention, the bottom support foam 300 is located below the module layout region 130, and the shape and size of the bottom support foam 300 are adapted to the PI film 110 of the module layout region 130. Thus, the bottom support foam 300 can be ensured to perfectly support and cooperate with the PI film 110 in the module layout region 130, so that the production and processing of the two are simpler. Specifically, the PI membrane 110 that district 130 was laid to the module is square structure, and multi-purpose square electric core module in the electric automobile lithium cell package at present, consequently lays the PI membrane 110 that district 130 was laid to the module and sets up to square structure more convenient and square electric core module battery package matching, and the suitability is stronger. Preferably, the PI film 110 in the PI heating film body 100 is formed by hollow punching. The hollowed-out stamping process is based on plastic deformation, a die and stamping equipment are utilized to apply pressure to a material, so that the sheet material is subjected to plastic deformation or separation, and a part (stamping part) with a certain shape, size and performance is obtained, and the hollowed-out holes 111 in the PI film 110 are suitable for mass production with low cost by adopting the most mature and efficient hollowed-out stamping technology in the mechanical manufacturing industry, so that the production efficiency is high, and the cost is low. And the connection joints and the wire switching design among the traditional heating films can be reduced, and the simplicity and the reliability of the electrical connection are ensured.

In the embodiment shown in fig. 4 and 5, the bottom support foam 300 is provided with adhesive backsizes 400 on both sides of the upper surface. Preferably, adhesive back glue 400 is arranged on two sides of the lower surface of the bottom support foam 300. The back adhesive is a product, and is generally pre-coated on the back of the product and separated by a separation film or release paper. The adhesive can be adhered after the release film or the release paper is removed before use, and is generally used for adhering thin materials or parts. The upper and lower surface design bonding gum 400 of bottom support bubble cotton 300 in this embodiment can make things convenient for its relative fixed when from the line location with PI membrane 110, has also made things convenient for the installation of heating membrane system simultaneously.

Referring to fig. 1 and fig. 2, as a preferred embodiment of the present invention, the heating membrane system assembly further includes a plug-in outlet 500, and the plug-in outlet 500 is respectively disposed at two ends of the PI heating membrane body 100 and is communicated with the serially connected resistance wires 120. The outlet end 500 with the plug-in is used for communicating a heating wire and an external power supply device to heat the resistance wire 120. The plug-in components are used for connecting an external power supply, so that the installation is more convenient. Preferably, the heating film system assembly further comprises a wire outlet end isolation foam 600, and the wire outlet end isolation foam 600 is wrapped at the connection position of the wire outlet end 500 with the plug-in unit and the resistance wire 120. The arrangement of the outlet end isolation foam 600 can perform leakage protection at the outlet end, and meanwhile, the outlet end is prevented from being worn by other parts, so that the condition of breakage is generated, and the service life of the outlet end 500 with the plug-in is ensured.

It should be noted that, although the above embodiments have been described herein, the invention is not limited thereto. Therefore, based on the innovative concepts of the present invention, the technical solutions of the present invention can be directly or indirectly applied to other related technical fields by making changes and modifications to the embodiments described herein, or by using equivalent structures or equivalent processes performed in the content of the present specification and the attached drawings, which are included in the scope of the present patent.

Claims

1. A heating film system assembly for a battery pack is characterized by comprising a PI heating film body and isolating foam, wherein the PI heating film body comprises a PI film and a resistance wire, the PI film is provided with a hollowed hole, the PI film is divided into at least two module layout areas by the hollowed hole, adjacent module layout areas are connected through the PI films on two sides of the hollowed hole, the resistance wire is coated inside the module layout areas, the resistance wires between the adjacent module layout areas are arranged in series, the opening positions of the hollowed holes are not overlapped with the layout areas of the resistance wire, and the isolating foam is respectively arranged on the PI films on two sides of the hollowed hole;

the isolation foam is a material foamed by plastic particles.

2. The heating film system assembly for a battery pack of claim 1, further comprising a bottom supporting foam, the PI heating film body disposed on the bottom supporting foam.

3. The heating film system assembly for battery pack of claim 2, wherein the bottom supporting foam is a combination foam composed of a combination of a silica gel foam and a microcellular foamed polypropylene.

4. The heating film system assembly for battery pack as claimed in claim 2, wherein the bottom supporting foam is located under the module layout region, and the bottom supporting foam has a shape and size matched with the PI film outline size of the module layout region.

5. The heating film system assembly for battery pack as claimed in claim 4, wherein the bottom supporting foam is provided with adhesive back glue on both sides of its upper surface.

6. The heating film system assembly for battery pack as claimed in claim 4, wherein the bottom supporting foam is provided with adhesive back glue on both sides of its lower surface.

7. The heating film system assembly for battery pack of claim 1, wherein the PI film in the PI heating film body is blanked by a knife die.

8. The heating film system assembly for battery pack as claimed in claim 1, wherein the PI film of the module layout region is a square structure.

9. The heating film system assembly for the battery pack as claimed in claim 1, further comprising a wire outlet end with a plug-in, wherein the wire outlet end with the plug-in is respectively disposed at two ends of the PI heating film body and is communicated with the serially disposed resistance wires.

10. The heating film system assembly for the battery pack as claimed in claim 9, wherein the heating film system assembly further comprises a wire outlet end isolation foam, and the wire outlet end isolation foam is wrapped at the connection between the wire outlet end with the plug-in unit and the resistance wire.