Bottom heating battery module, battery pack and new energy automobile

Abstract

The utility model belongs to the technical field of battery module heat management, and particularly relates to a bottom heating battery module, a battery pack and a new energy automobile. According to the bottom heating battery module, the heating film is arranged at the bottom of the battery cell array and is bonded with the battery module through the heat-conducting structural adhesive, the heating film does not need to be fixed by virtue of battery cell structures such as an end plate, the independence and the compatibility are high, and the bottom heating battery module can be compatible with a CTP / CTC structure without the end plate. The heating film is connected with the battery cell array through the heat-conducting structural adhesive layer, and the area of the heat-conducting structural adhesive layer is larger than or equal to that of the heating film, so that the heating film is not in direct contact with the battery cells, and the dry burning risk caused by local high temperature is avoided; due to the fact that the heating film is arranged on the bottom face, the heating film can be tightly attached to the heat-conducting structural adhesive layer under the dead weight of the battery cell array, bolt stretching and tensioning in a traditional scheme are not needed, meanwhile, the heat-conducting structural adhesive can achieve a certain buffering effect, and the tearing risk of the heating film is reduced. In a preferable embodiment, the heating film is provided with heating areas with different powers so as to meet the heating requirements of the battery cell array.

Description

Technical Field

[0001] The utility model belongs to the technical field of battery module thermal management, and specifically relates to a bottom heating battery module, a battery pack and a new energy vehicle. Background Art

[0002] At present, battery packs heated by heating film are generally fixed on the side of the module and connected to the module end plate with fixing bolts. Figure 1 The module consists of several battery cells, end plates, steel strips, fastening bolts, and a heating film. In the original module, the heating film is placed on the side of the battery cell and fixed to the end plates on both sides with fastening bolts. The end plates are used to clamp the module cells together; steel tie wraps are used to secure the module and heating film; and the bolts lock the end plates on both sides to secure the entire module.

[0003] However, this fixing method is not compatible with the CTP / CTC battery pack structure without end plates, does not conform to market development trends, has low versatility and high development costs; to ensure the heating effect, the heating film is generally tightly attached to the module battery cell and is in a "stretched" state, which poses the risk of dry burning and heating film tearing; the battery cells near the module end plate are lower in temperature than the middle battery cells, and the even distribution of resistance wires in the heating film causes the temperature of the middle battery cells of the module to gradually become higher than the temperature of the battery cells near the end plate during the heating process, which cannot effectively control the large temperature difference of the module battery cells during the heating process.

[0004] Chinese patent application number CN202410514193.6 discloses a cold plate structure, battery pack, and vehicle with an integrated heating film. The heating film is integrated into the cold plate structure, and the cold plate structure is set at the bottom of the battery pack. Although it does not have the problem of heating the side of the heating film mentioned above, its bottom surface heating solution relies on the solution of setting a liquid cooling plate at the bottom of the battery pack and is not compatible with other liquid cooling solutions. In addition, integrating the heating film into the cold plate will increase the thermal resistance from the liquid cooling part to the battery cell, and reduce the heat conduction effect of the liquid cooling.

[0005] Therefore, how to provide a battery module heating solution with good compatibility is a technical problem that needs to be solved urgently in this field. Utility Model Content

[0006] In response to the existing phenomenon, the present invention provides a bottom heating battery module, a battery pack and a new energy vehicle, which at least solve one of the above technical problems.

[0007] The technical solution provided in this application is a bottom heating battery module, including a battery cell array, a heating film arranged at the bottom of the battery cell array for heating the battery cell array, and a thermally conductive structural adhesive layer connecting the battery cell array and the heating film; the area of ​​the thermally conductive structural adhesive layer is greater than or equal to the area of ​​the heating film and at least covers the surface of the heating film on the side close to the battery cell array.

[0008] Preferably, the thickness of the thermal conductive structural adhesive layer is 1-5 mm.

[0009] Preferably, the heating film is integrally arranged near the center of the bottom surface of the battery cell array.

[0010] Preferably, the heating film includes a first heating area and a second heating area distributed from the inside to the outside, the second heating area is close to the end of the battery cell array, and the heating power per unit area in the second heating area is greater than that in the first heating area.

[0011] Preferably, the heating film comprises heating wires, and the density of the heating wires in the second heating region is greater than that in the first heating region.

[0012] Preferably, it includes two end plates, the battery cell array is located between the two end plates and fixed by a cable tie, and the wiring harness connector for connecting the heating film to the power supply is located at the bottom of the end plates.

[0013] A battery pack comprises a box body and the above-mentioned bottom heating battery module.

[0014] Preferably, the bottom of the box is connected to the heating film through a second heat-conducting structural adhesive layer, the area of ​​the second heat-conducting structural adhesive layer is greater than or equal to the area of ​​the heating film, and the thickness of the second heat-conducting structural adhesive layer is 1-5 mm.

[0015] Preferably, a support buffer portion for supporting and / or buffering is provided between the bottom of the box and the bottom surface of the battery cell array.

[0016] A new energy vehicle chassis comprises the above-mentioned bottom heating battery module.

[0017] The beneficial effects of the present application are as follows: the bottom heating battery module of the present application sets the heating film at the bottom of the battery cell array, and is bonded to the battery module through thermally conductive structural adhesive. The heating film can be fixed without the help of battery cell structures such as end plates. It has strong independence and compatibility and is compatible with CTP / CTC structures without end plates. The heating film is connected to the battery cell array through a thermally conductive structural adhesive layer. The area of ​​the thermally conductive structural adhesive layer is greater than or equal to the area of ​​the heating film, so that the heating film does not directly contact the battery cells, avoiding the risk of dry burning caused by local high temperature. Since it is set on the bottom surface, the heating film can be tightly attached to the thermally conductive structural adhesive layer under the weight of the battery cell array, without the need for bolts to stretch and tighten as in traditional solutions. At the same time, the thermally conductive structural adhesive can play a certain buffering role, reducing the risk of tearing of the heating film. In a preferred embodiment, the heating film is provided with heating areas of different powers to match the heating requirements of the battery cell array. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The accompanying drawings, which are incorporated into and constitute a part of the specification, illustrate embodiments of the present invention and, together with the description, serve to explain the principles of the present invention. In these drawings, similar reference numerals are used to represent similar elements. The drawings described below are some embodiments of the present invention, but not all. Those skilled in the art can derive other drawings from these drawings without inventive effort.

[0019] Figure 1 This is a schematic diagram of a side-heating battery module in the prior art;

[0020] Figure 2 This is an exploded schematic diagram of an embodiment of the present utility model;

[0021] Figure 3 A bottom view schematically shows an embodiment of the present invention;

[0022] Figure 4 for Figure 2 Schematic diagram of the heating film 2;

[0023] Figure 5 A side view of another embodiment of the present invention;

[0024] Reference numerals:

[0025] Battery cell array 1, heating film 2, first heating area 21, second heating area 22, non-heating area 23, wiring harness connector 24, thermal conductive structural adhesive layer 3, second thermal conductive structural adhesive layer 4, box 5, support buffer part 6. DETAILED DESCRIPTION

[0026] To make the purpose, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0027] In the description of this application, unless otherwise expressly specified or limited, the terms "connected," "connected," and "fixed" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and can refer to internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0028] In this application, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may include the first and second features being in direct contact, or may include the first and second features being in contact not directly but through another feature between them. Moreover, a first feature being "above," "above," and "above" a second feature may include the first feature being directly above or obliquely above the second feature, or may simply mean that the first feature is higher in level than the second feature. A first feature being "below," "below," and "below" a second feature may include the first feature being directly below or obliquely below the second feature, or may simply mean that the first feature is lower in level than the second feature.

[0029] In the description of this embodiment, the terms "upper," "lower," "left," "right," and other orientations or positional relationships are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely for ease of description and simplified operation. They do not indicate or imply that the devices or components referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on this application. Furthermore, the terms "first" and "second" are used solely for descriptive purposes and have no special meanings.

[0030] refer to Figure 2-3 Embodiment 1 provides a bottom heating battery module, including a battery cell array 1, a heating film 2 arranged at the bottom of the battery cell array 1 for heating the battery cell array 1, and a thermally conductive structural adhesive layer 3 connecting the battery cell array 1 and the heating film 2; the area of ​​the thermally conductive structural adhesive layer 3 is greater than or equal to the area of ​​the heating film 2 and at least covers the surface of the heating film 2 on the side close to the battery cell array 1.

[0031] The bottom heating battery module of the present application sets the heating film at the bottom of the battery cell array, and adheres it to the battery module through thermal conductive structural adhesive. It can fix the heating film without the help of battery cell structures such as end plates. It has strong independence and compatibility and is compatible with CTP / CTC structures without end plates. The heating film 2 is connected to the battery cell array 1 through a thermal conductive structural adhesive layer. The area of ​​the thermal conductive structural adhesive layer 3 is greater than or equal to the area of ​​the heating film 2 and at least covers the surface of the heating film 2 on the side close to the battery cell array 1, so that the heating film 2 does not directly contact the battery cells, avoiding the risk of dry burning caused by local high temperature. Since it is set on the bottom surface, the heating film 2 can be tightly attached to the thermal conductive structural adhesive layer 3 under the weight of the battery cell array 1, without the need to use bolts to stretch and tighten as in traditional solutions. At the same time, the thermal conductive structural adhesive can play a certain buffering role, reducing the risk of tearing of the heating film.

[0032] It can be understood that the thermal conductive structural adhesive layer 3 of the present application is formed by coating and curing the thermal conductive structural adhesive. Thermal conductive structural adhesive is a general technology in this field, and people in this field are capable of obtaining and selecting suitable thermal conductive structural adhesive to achieve the purpose of this application.

[0033] In this embodiment, the thickness of the thermal conductive structural adhesive layer 3 is 3 mm. When the thickness of the thermal conductive structural adhesive layer 3 is 1-5 mm, it has a good bonding effect and a buffering effect, and controls the overall thickness of the battery module.

[0034] like Figure 3 In this embodiment, the area of ​​the heating film 2 is 60% of the bottom area of ​​the cell array 1, which fully meets the heating requirements of the cell array 2. Generally, when the area of ​​the heating film 2 is greater than or equal to 50% of the bottom area of ​​the cell array 1, the heating requirements of the cell array 2 are even better met. The area on the bottom of the cell array 1 not connected to the heating film 2 can be used to install support or buffer components to prevent the cell array 1 from crushing the heating film 2.

[0035] like Figure 3 In this embodiment, the heating film 2 is integrally arranged near the center of the bottom surface of the cell array 1. The integrated structure of the heating film 2 simplifies implementation and reduces the number of wiring harnesses required for the heating film 2. Only one wiring harness is required at each end to connect to the power supply, reducing space usage. The central arrangement near the bottom surface of the cell array 1 allows for efficient heat transfer to the entire cell array 1, resulting in high heating efficiency and uniformity. The combination of these two features allows for a simple solution that meets operational requirements.

[0036] like Figure 4 In this embodiment, the heating film 2 includes a first heating area 21 and a second heating area 22 distributed from the inside to the outside. The heating power per unit area in the second heating area 22 is greater than that in the first heating area 21. The second heating area 22 is close to the end of the battery cell array 10. The temperature of the battery cells near the two ends of the battery cell array 1 is lower and requires a larger amount of heating. Setting heating areas with different powers is conducive to sufficient heating and effectively suppressing the phenomenon of excessive temperature difference in the module battery cells. In this embodiment, the heating power per unit area in the second heating area 22 is 1.23 times that of the first heating area 21. In other embodiments, the above effect can be better achieved when the heating power per unit area in the second heating area 22 is 1.1 to 1.5 times that of the first heating area 21. In this embodiment, the length of each of the two second heating areas 22 is 0.15 times that of the first heating area 21. In other embodiments, the above effect can be better achieved when the length of each of the two second heating areas 22 is 0.1 to 0.3 times that of the first heating area 21.

[0037] Specifically, the heating film 2 includes heating wires, and the density of heating wires in the second heating region 22 is greater than that in the first heating region 21. The heating wires are unevenly distributed within the heating film, forming heating regions with different heating powers per unit area. Because heating wires cannot be installed at the edges, there is also a non-heating region 23.

[0038] This embodiment includes two end plates 11, the battery cell array 1 is arrayed between the two end plates 11 and fixed by a cable tie 12, and the wiring harness connector 24 for connecting the heating film 2 to the power supply is located at the bottom of the end plate 11, which protects the wiring harness connector 24 while saving space.

[0039] In addition, the cell connection system (CCS), collection harness and other structures in this embodiment are integrated on the top of the cell array, and a number of connection ports and reinforcing ribs are also provided on the end plate 11.

[0040] Example 2 provides a battery pack, including the bottom heating battery module of Example 1 and the box body 5, which can have all the beneficial effects thereof.

[0041] Please refer to Figure 5 Schematic side view of the embodiment. In this embodiment, the bottom of the housing 5 is connected to the heating film 2 via a second thermally conductive structural adhesive layer 4. The area of ​​the second thermally conductive structural adhesive layer 4 is greater than or equal to the area of ​​the heating film 2, and the thickness of the second thermally conductive structural adhesive layer 4 is 1-5 mm. The second thermally conductive structural adhesive layer 4 also provides thermal conductivity and buffering between the bottom of the housing 5 and the heating film 2, further protecting the heating film 2 and improving thermal conductivity, facilitating implementation and installation.

[0042] Continue to refer Figure 5 In this embodiment, a support and buffer portion 6 is provided between the bottom of the housing 5 and the bottom surface of the cell array 1 to distribute the weight exerted on the heating film 2 and further prevent cracking of the heating film 2. In this embodiment, the support and buffer portion 6 is specifically configured as a third thermally conductive structural adhesive layer. In other embodiments, other supporting and / or buffering methods, such as a mechanical buffer / support structure, may also be used.

[0043] Example 3 provides a new energy vehicle equipped with the battery pack of Example 2, which has all the beneficial effects of Example 2. In other embodiments of new energy vehicles, since the heating film 2 in the bottom heating battery module provided by this application is fixed without the help of end plates and other structures, it is also compatible with CTP / CTC and other structures.

[0044] The contents described above can be implemented individually or in combination in various ways, and these variations are all within the scope of protection of the present invention.

[0045] It should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply the existence of any such actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article, or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or device. In the absence of further limitations, an element defined by the statement "comprising a ..." does not exclude the presence of other identical elements in the process, method, article, or device comprising the element.

[0046] The above content is a further detailed description of the present invention in conjunction with specific preferred embodiments, and the specific embodiments of the present invention are not limited to these descriptions. For those skilled in the art of the present invention, several simple deductions or substitutions can be made without departing from the concept of the present invention, and all of these should be considered to fall within the scope of protection of the present invention.

Claims

1. A bottom heating battery module, characterized in that: The invention comprises a cell array (1), a heating film (2) arranged at the bottom of the cell array (1) for heating the cell array (1), and a heat-conducting structural adhesive layer (3) connecting the cell array (1) and the heating film (2); the area of ​​the heat-conducting structural adhesive layer (3) is greater than or equal to the area of ​​the heating film (2) and at least covers the surface of the heating film (2) on the side close to the cell array (1).

2. The bottom heating battery module according to claim 1, characterized in that: The thickness of the thermal conductive structural adhesive layer (3) is 1-5 mm.

3. The bottom heating battery module according to claim 1, characterized in that: The heating film (2) is integrally arranged near the center of the bottom surface of the battery cell array (1).

4. The bottom heating battery module according to claim 1, characterized in that: The heating film (2) comprises a first heating region (21) and a second heating region (22) distributed from the inside to the outside, the second heating region (22) being close to the end of the battery cell array (1), and the heating power per unit area in the second heating region (22) being greater than that in the first heating region (21).

5. The bottom heating battery module according to claim 4, characterized in that: The heating film (2) comprises heating wires, and the density of the heating wires in the second heating area (22) is greater than that in the first heating area (21).

6. The bottom heating battery module according to claim 1, characterized in that: It comprises two end plates (11), the battery cell array (1) is located between the two end plates (11) and is fixed by a cable tie (12), and the wiring harness connector (24) for connecting the heating film (2) to a power source is located at the bottom of the end plates (11).

7. A battery pack, characterized in that: It comprises a box body (5) and a bottom heating battery module as described in any one of claims 1 to 6.

8. The battery pack according to claim 7, characterized in that: The bottom of the box (5) is connected to the heating film (2) via a second heat-conducting structural adhesive layer (4); the area of ​​the second heat-conducting structural adhesive layer (4) is greater than or equal to the area of ​​the heating film (2); and the thickness of the second heat-conducting structural adhesive layer (4) is 1-5 mm.

9. The battery pack according to claim 7, characterized in that: A support buffer portion (6) for supporting and / or buffering is provided between the bottom of the box (5) and the bottom surface of the battery cell array (1).

10. A new energy vehicle, characterized in that: The invention comprises the bottom heating battery module according to any one of claims 1 to 6.

Images