Power battery module

Abstract

The utility model discloses a power battery module, which is characterized in that a lower base film and an upper base film are superposed on the lower surface or the side surface of the power battery module, a plurality of heating units corresponding to battery cells are arranged between the lower base film and the upper base film along the length direction, and the adjacent heating units are electrically connected through first metal wires. Each heating unit comprises a plurality of second metal wires which are arranged in parallel, a first spacing area is arranged between every two adjacent second metal wires and is connected end to end, a second spacing area is arranged between every two adjacent heating units, and strip-shaped through holes are formed in the lower base film and the upper base film in the second spacing areas; a third spacer region is arranged between the strip-shaped through hole parallel to the second metal wire and the adjacent heating unit, and the width of the third spacer region is larger than that of the first spacer region. According to the utility model, on the basis of reducing mutual contact among the metal wires, the condition of overall dry burning is reduced, the metal wires can be prevented from being exposed, and the overall safety performance is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of power batteries, and in particular to a power battery module. Background Art

[0002] As new energy vehicles have higher requirements for environmental adaptability, vehicles will have a significant reduction in mileage in low temperature environments. For power battery modules, in low temperature environments, the slow diffusion of lithium ions inside lithium-ion power batteries, the decrease in ion conductivity in the electrolyte, the increase in internal contact resistance, and the slowdown of various chemical reaction rates lead to a sharp decline in the battery's charge and discharge capabilities and available capacity. In particular, lithium precipitation will occur in low temperature environments. When lithium dendrites grow to a certain extent, they will pierce the diaphragm, leading to some safety accidents. Therefore, power battery modules are generally treated with heat preservation during use.

[0003] Most of the existing technologies for heat preservation of power battery modules adopt a method of combining a heating circuit with a heating wire and an insulating film. Generally, the insulation function is achieved by connecting the heating circuit to allow the heating wire to generate heat. However, the battery cells inside the power battery module will expand during use. The expanded battery cells will squeeze the insulating film, causing the insulating film to deform, and the heating wires of the heating circuit inside the insulating film will also be squeezed and shifted. After the battery module has been used for a period of time, the insulating film is difficult to recover, resulting in the insulation film being separated from the battery cell and the heating wire being dry-burned. This also reduces the restraint on the heating wire and increases the risk of exposure and contact between the heating wires, affecting the safety of the power battery module. Summary of the invention

[0004] The utility model aims to provide a power battery module, which reduces the risk of metal wires contacting each other, reduces the overall dry burning, and can prevent the metal wires from being exposed, thereby improving the overall safety performance.

[0005] To achieve the above-mentioned purpose, the technical solution adopted by the utility model is: a power battery module, comprising: an input end, an output end and a plurality of battery cells arranged in parallel, a lower base film and an upper base film are stacked on the lower surface or side surface of the plurality of battery cells, a plurality of heating units corresponding to the battery cells are arranged between the lower base film and the upper base film and along the length direction, adjacent heating units are electrically connected through a first metal wire, and the heating units located at both ends of the lower base film and the upper base film respectively have an input interface area electrically connected to the input end and an output interface area electrically connected to the output end;

[0006] The heating unit includes a plurality of second metal wires arranged in parallel, with a first spacing area between adjacent second metal wires and connected end to end, a second spacing area between adjacent heating units, a strip through hole located inside the second spacing area and opened on the lower base film and the upper base film, a third spacing area between the strip through hole arranged parallel to the second metal wire and the adjacent heating unit, and the width of the third spacing area is greater than the width of the first spacing area, and the first metal wire is located in the middle position between the end of the strip through hole and the edge of the base film.

[0007] The further improved scheme in the above technical scheme is as follows:

[0008] 1. In the above solution, the distance between the first metal wire and the end of the strip-shaped through hole is greater than the width of the third spacing area.

[0009] 2. In the above solution, the distribution density of the second metal wires at the two ends of the lower base film and the upper base film is greater than the distribution density of the second metal wires in the middle of the lower base film and the upper base film.

[0010] 3. In the above solution, an adhesive layer is provided on the upper surface of the lower base film and / or the lower surface of the upper base film.

[0011] 4. In the above solution, the diameter of the first metal wire is 10μm~300μm.

[0012] 5. In the above solution, the diameter of the second metal wire is 10μm~300μm.

[0013] Due to the application of the above technical solution, the utility model has the following advantages compared with the prior art:

[0014] The utility model power battery module is connected end to end by a second metal wire, and a first spacing area is provided between adjacent second metal wires, a second spacing area is provided between adjacent heating units, and the width of the second spacing area is greater than that of the first spacing area, and a strip through hole is provided on the lower base film and the upper base film and located inside the second spacing area, and the first metal wire is located in the middle position between the end of the strip through hole and the edge of the lower base film and the upper base film, and the expansion stress of the battery cell can be released through the strip through hole, thereby weakening the deformation of the lower base film and the upper base film when the battery cell expands, reducing the probability of the upper base film and the lower base film being separated from the battery cell, improving the overall safety performance, and being conducive to ensuring the reliability of the power battery module during long-term use. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Attached Figure 1 This is a schematic diagram of the overall structure of the power battery module of the utility model;

[0016] Attached Figure 2It is a partial structural stereogram of the power battery module of the utility model;

[0017] Attached Figure 3 This is a schematic diagram of the partial internal structure of the power battery module of the utility model;

[0018] Attached Figure 4 For the utility model Figure 3 An enlarged schematic diagram of point B;

[0019] Attached Figure 5 It is a schematic cross-sectional view taken along line A-A' of the first embodiment of the utility model;

[0020] Attached Figure 6 It is a schematic cross-sectional view taken along line A-A' of a second embodiment of the present invention.

[0021] In the above figures: 100, battery cell; 200, power battery module; 1, heating unit; 101, second metal wire; 2, strip-shaped through hole; 3, input interface area; 4, output interface area; 5, first metal wire; 6, input end; 7, output end; 8, lower base film; 9, upper base film; 10, second spacer area; 11, third spacer area; 12, adhesive layer; 13, first spacer area. DETAILED DESCRIPTION

[0022] The present invention can be further understood through the specific embodiments given below, but they are not intended to limit the present invention.

[0023] Embodiment 1: A power battery module, comprising: an input terminal 6, an output terminal 7 and a plurality of battery cells 100 arranged in parallel, a lower base film 8 and an upper base film 9 are stacked on the lower surface or side surface of the plurality of battery cells 100, a plurality of heating units 1 corresponding to the battery cells 100 are arranged between the lower base film 8 and the upper base film 9 and along the length direction, adjacent heating units 1 are electrically connected through a first metal wire 5, and the heating units 1 located at both ends of the lower base film 8 and the upper base film 9 respectively have an input interface area 3 electrically connected to the input terminal 6 and an output interface area 4 electrically connected to the output terminal 7;

[0024] The heating unit 1 includes a plurality of second metal wires 101 arranged in parallel, a first spacing area 13 is provided between adjacent second metal wires 101 and the wires are connected end to end, a second spacing area 10 is provided between adjacent heating units 1, and a strip-shaped through hole 2 is provided inside the second spacing area 10 and on the lower base film 8 and the upper base film 9;

[0025] There is a third spacing area 11 between the strip through hole 2 arranged parallel to the second metal wire 101 and the adjacent heating unit 1, and the width of the third spacing area 11 is greater than the width of the first spacing area 13, and the first metal wire 5 is located in the middle position between the end of the strip through hole 2 and the edge of the base film.

[0026] The distance between the first metal conductive line 5 and the end of the strip-shaped through hole 2 is greater than the width of the third spacing area 11 .

[0027] The lower base film 8 and the upper base film 9 are both PI films.

[0028] The distribution density of the second metal wires 101 at the two ends of the lower base film 8 and the upper base film 9 is greater than the distribution density of the second metal wires 101 in the middle of the lower base film 8 and the upper base film 9. During the use of the power battery module, since the temperature at both ends of the module drops faster, increasing the distribution density of the second metal wires 101 at both ends of the lower base film 8 and the upper base film 9 is beneficial to improving the heating power at both ends of the power battery module and improving the uniformity of the overall temperature distribution.

[0029] An adhesive layer 12 is provided on the upper surface of the lower base film 8 and the lower surface of the upper base film 9 .

[0030] For the adhesive layer, the adhesive layer can be coated on the upper surface of the lower base film and the lower surface of the upper base film, and the metal wires are printed on the adhesive layer that has not been completely cured. The stacked upper and lower base films will cover the printed metal wires.

[0031] The diameter of the first metal wire 5 is 20 μm.

[0032] The diameters of the first metal wire 5 and the second metal wire 101 are the same.

[0033] Embodiment 2: A power battery module, comprising: an input terminal 6, an output terminal 7 and a plurality of battery cells 100 arranged in parallel, a lower base film 8 and an upper base film 9 are stacked on the lower surface or side surface of the plurality of battery cells 100, a plurality of heating units 1 corresponding to the battery cells 100 are arranged between the lower base film 8 and the upper base film 9 and along the length direction, adjacent heating units 1 are electrically connected through a first metal wire 5, and the heating units 1 located at both ends of the lower base film 8 and the upper base film 9 respectively have an input interface area 3 electrically connected to the input terminal 6 and an output interface area 4 electrically connected to the output terminal 7;

[0034] The heating unit 1 includes a plurality of second metal wires 101 arranged in parallel, with a first spacing area 13 between adjacent second metal wires 101 and connected end to end, and a second spacing area 10 between adjacent heating units 1, which is conducive to reducing the risk of contact between the first metal wires and the second metal wires, and between adjacent second metal wires;

[0035] A strip through hole 2 is provided inside the second spacing area 10 and on both the lower base film 8 and the upper base film 9. A third spacing area 11 is provided between the strip through hole 2 arranged parallel to the second metal wire 101 and the adjacent heating unit 1, and the width of the third spacing area 11 is greater than that of the first spacing area 13. The first metal wire 5 is located in the middle position between the end of the strip through hole 2 and the edge of the base film.

[0036] The distance between the first metal conductive line 5 and the end of the strip-shaped through hole 2 is greater than the width of the third spacing area 11 .

[0037] The lower base film 8 is a PET film, and the upper base film 9 is a PET film.

[0038] An adhesive layer 12 is disposed on the upper surface of the lower base film 8 .

[0039] The diameter of the second metal wire 101 is 200 μm.

[0040] The diameters of the first metal wire 5 and the second metal wire 101 are the same.

[0041] When the above-mentioned power battery module is adopted, the risk of contact between the first metal wire and the second metal wire, and between adjacent second metal wires is reduced. The expansion stress of the battery cell can be released through the strip through hole, thereby weakening the deformation of the lower base film and the upper base film when the battery cell expands, which is beneficial to slowing down the damage of the lower base film and the upper base film, and reducing the situation where the upper base film and the lower base film are separated from the battery cell and cause the whole to dry burn. It can also prevent the second metal wire and the first metal wire from being exposed during the deformation of the lower base film and the upper base film, thereby improving the overall safety performance and helping to ensure the reliability of the power battery module during long-term use.

[0042] The above embodiments are only for illustrating the technical concept and features of the utility model, and their purpose is to enable people familiar with the technology to understand the content of the utility model and implement it accordingly, and they cannot be used to limit the protection scope of the utility model. Any equivalent changes or modifications made according to the spirit of the utility model should be included in the protection scope of the utility model.

Claims

1. A power battery module, comprising: An input terminal (6), an output terminal (7) and a plurality of battery cells (100) arranged in parallel, characterized in that: a lower base film (8) and an upper base film (9) are stacked on the lower surface or side surface of the plurality of battery cells (100), a plurality of heating units (1) corresponding to the battery cells (100) are arranged between the lower base film (8) and the upper base film (9) and along the length direction, adjacent heating units (1) are electrically connected via a first metal wire (5), and the heating units (1) located at both ends of the lower base film (8) and the upper base film (9) respectively have an input interface area (3) electrically connected to the input terminal (6) and an output interface area (4) electrically connected to the output terminal (7); The heating unit (1) comprises a plurality of second metal wires (101) arranged in parallel, a first spacing area (13) being provided between adjacent second metal wires (101) and being connected end to end, a second spacing area (10) being provided between adjacent heating units (1), a strip through hole (2) being provided in the second spacing area (10) and on both the lower base film (8) and the upper base film (9), and the first metal wire (5) being located in the middle between the end of the strip through hole (2) and the edge of the base film.

2. The power battery module according to claim 1, characterized in that: A third spacing area (11) is provided between the strip-shaped through hole (2) arranged parallel to the second metal wire (101) and the adjacent heating unit (1), and the width of the third spacing area (11) is greater than the width of the first spacing area (13).

3. The power battery module according to claim 2, characterized in that: The distance between the first metal wire (5) and the end of the strip-shaped through hole (2) is greater than the width of the third spacing area (11).

4. The power battery module according to claim 1, characterized in that: The distribution density of the second metal wires (101) at the two ends of the lower base film (8) and the upper base film (9) is greater than the distribution density of the second metal wires (101) in the middle of the lower base film (8) and the upper base film (9).

5. The power battery module according to claim 1, characterized in that: An adhesive layer (12) is provided on the upper surface of the lower base film (8) and / or the lower surface of the upper base film (9).

6. The power battery module according to claim 1, characterized in that: The diameter of the first metal wire (5) is 10 μm to 300 μm.

7. The power battery module according to claim 1, characterized in that: The diameter of the second metal wire (101) is 10 μm to 300 μm.

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