Battery pack

Abstract

The utility model belongs to a battery pack in the technical field of power batteries. Comprising a lower shell with an exhaust part, a battery cell stacking body, first polystyrene foam and a high-temperature-resistant element, the battery cell stacking body is arranged in the lower shell and comprises a plurality of soft package battery cells, the bottom side of the battery cell stacking body is fixedly connected with a bottom plate of the lower shell, a first part area between the tab side of the battery cell stacking body and the lower shell forms a glue pouring area, and a second part area forms an exhaust area; the glue filling area is filled with the first polystyrene foam; the high-temperature-resistant element is mounted in the exhaust area, separates the tabs of the plurality of soft package battery cells and is matched with the first polystyrene foam to define a plurality of exhaust channels, and the exhaust channels correspond to the soft package battery cells and are suitable for being communicated with the exhaust part when the soft package battery cells are exhausted. According to the battery pack, the stability of the battery cell stack is improved, and when the soft package battery cells are subjected to thermal runaway, high-temperature flue gas is exhausted through the exhaust channels corresponding to the soft package battery cells subjected to thermal runaway, so that other soft package battery cells are prevented from being influenced, and the safety performance of the battery pack is improved.

Description

Technical Field

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

[0002] When thermal runaway occurs in the battery cell stack in the battery pack, the high-temperature smoke generated will be discharged from the pole ear side of the battery cell stack. The discharged high-temperature smoke will easily affect the pole ears of the soft-pack batteries in the battery cell stack, and easily affect other soft-pack batteries that have not experienced thermal runaway, thereby easily causing a short circuit between the soft-pack batteries, and thus causing safety accidents, resulting in poor safety performance. Utility Model Content

[0003] In view of the shortcomings of the prior art described above, the purpose of the present invention is to provide a battery pack for solving the problem in the prior art that when thermal runaway occurs in soft-pack batteries, high-temperature smoke easily affects other soft-pack batteries and causes short circuits, so as to improve the safety performance of the battery pack.

[0004] In order to achieve the above-mentioned object and other related objects, the utility model provides a battery pack, comprising:

[0005] A lower housing having an exhaust portion;

[0006] A battery cell stack, the battery cell stack comprising a plurality of stacked soft-pack battery cells, the battery cell stack being disposed in the lower shell, the bottom side of the battery cell stack being connected and fixed to the bottom plate of the lower shell, the first partial area between the tab side of the battery cell stack and the lower shell being formed as a glue filling area, and the second partial area being formed as an exhaust area;

[0007] A first foam glue, wherein the first foam glue is filled in the glue pouring area;

[0008] A high temperature resistant component is installed in the exhaust area and separates the tabs of the plurality of soft-pack batteries, and cooperates with the first foam glue to define a plurality of exhaust channels, wherein the exhaust channels correspond to the soft-pack batteries and are suitable for being connected to the exhaust part when the soft-pack batteries are exhausted.

[0009] Optionally, the high temperature resistant element includes a main body and a plurality of isolation parts spaced apart along the stacking direction of the soft-pack battery cells, one end of the isolation part is connected to the side of the main body facing the first foam glue, and the other end of the isolation part extends between the pole ears of two adjacent soft-pack battery cells and adheres to the first foam glue.

[0010] Optionally, it also includes an upper cover, which is located on the top side of the battery cell stack and covers the lower shell, the glue filling area and the exhaust area are distributed along the height direction of the battery cell stack, and the exhaust area is located between the upper cover and the glue filling area.

[0011] Optionally, a side of the main body facing away from the first foam adhesive is in contact with the upper cover.

[0012] Optionally, the thickness of the isolation portion gradually decreases from an end away from the exhaust portion to an end close to the exhaust portion.

[0013] Optionally, the lower shell includes an end beam, an exhaust bin is provided in the end beam, and an explosion-proof valve suitable for exhausting the exhaust bin is installed on the end beam; the pole ear side of the battery cell stack includes a first pole ear side facing the end beam, the exhaust channel is located on the first pole ear side of the battery cell stack, and the exhaust part is arranged on the end beam to connect the exhaust channel and the exhaust bin.

[0014] Optionally, the number of the battery cell stacks is two, the lower shell further includes a middle beam located between the two battery cell stacks, the pole ear side of the battery cell stack further includes a second pole ear side facing the middle beam, and a second foamed gel is filled between the second pole ear side of the battery cell stack and the middle beam.

[0015] Optionally, the end wall of the high temperature resistant element facing the end beam is in close contact with and interference fit with the end beam.

[0016] Optionally, the exhaust portion includes an exhaust hole, and the exhaust hole is covered with a high temperature resistant patch.

[0017] Optionally, the high temperature resistant element includes a ceramic foam piece.

[0018] Optionally, the bottom side of the battery cell stack is directly bonded and fixed to the bottom plate of the lower shell by means of a heat-conductive structural adhesive.

[0019] Optionally, in the height direction of the battery cell stack, the distance between the top of the tab of the soft-pack battery cell and the bottom plate is H1, the distance between the top of the first foam glue and the bottom plate is H2, H1≤H2, and the first foam glue covers the tab of the soft-pack battery cell.

[0020] As described above, the battery pack of the utility model has at least the following beneficial effects: the bottom side of the battery cell stack is connected and fixed to the lower shell, and the first foam glue is filled between the ear side of the battery cell stack and the lower shell, which is beneficial to improving the stability of the battery cell stack and preventing short circuits caused by collisions during transportation and vibration and impact; based on this, the ear side of the battery cell stack and part of the lower shell are not filled with the first foam glue, but the ears of adjacent soft-pack battery cells are separated by high-temperature resistant elements, which not only ensures the stability of the structure, but also when the soft-pack battery cell has thermal runaway, the high-temperature smoke can be discharged through the exhaust channel corresponding to the soft-pack battery cell that has thermal runaway, avoiding affecting other soft-pack battery cells, which is beneficial to preventing short circuits and further improving the safety performance of the battery pack. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a structural schematic diagram of a battery pack according to an embodiment of the present utility model;

[0022] Figure 2 for Figure 1 Schematic diagram of the explosion of the battery pack;

[0023] Figure 3 for Figure 1 The main view of the battery pack;

[0024] Figure 4 for Figure 3 Sectional view at AA in the middle;

[0025] Figure 5 for Figure 4 A magnified schematic diagram of the part B in the middle;

[0026] Figure 6 for Figure 3 A partial enlarged schematic diagram of the cross section at CC in the middle;

[0027] Figure 7 for Figure 2 A schematic diagram of the structure of the middle battery cell stack and the lower shell;

[0028] Figure 8 for Figure 7 A top view of the middle cell stack and the lower shell;

[0029] Fig. 9 for Figure 2 A schematic diagram of the structure of a medium-high temperature resistant component from the first perspective;

[0030] Fig.10 for Figure 2 Second perspective structural diagram of medium and high temperature resistant components.

[0031] Part Number Description

[0032] Lower shell 1, bottom plate 11, side beam 12, end beam 13, exhaust part 131, exhaust chamber 132, middle beam 14, battery cell stack 2, soft-pack battery cell 21, first foam glue 31, second foam glue 32, upper cover 4, high temperature resistant component 5, main body 51, isolation part 52, exhaust channel 6, explosion-proof valve 7, high temperature resistant patch 8. DETAILED DESCRIPTION

[0033] The following is a description of the implementation of the present invention by means of specific embodiments. People familiar with the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification.

[0034] It should be noted that the structures, proportions, sizes, etc. illustrated in the drawings of this specification are only used to match the contents disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the limiting conditions for the implementation of the utility model, so they have no substantial technical significance. Any modification of the structure, change of the proportion relationship or adjustment of the size, without affecting the effects and purposes that can be achieved by the utility model, should still fall within the scope of the technical content disclosed by the utility model. At the same time, the terms such as "upper", "lower", "left", "right", "middle" and "one" quoted in this specification are only for the convenience of description, and are not used to limit the scope of the implementation of the utility model. The change or adjustment of their relative relationship should also be regarded as the scope of the implementation of the utility model without substantial change of the technical content.

[0035] See also Figures 1 to 4 , Fig. 9 and Fig.10 In some optional embodiments, the present application provides a battery pack, including a lower shell 1, a battery cell stack 2, a first foam glue 31 and a high temperature resistant element 5. In addition to the above components, the battery pack may also include an upper cover 4. The lower shell 1 has an exhaust portion 131; the battery cell stack 2 includes a plurality of stacked soft-packed batteries 21, the battery cell stack 2 is arranged in the lower shell 1, the bottom side of the battery cell stack 2 is connected and fixed to the bottom plate 11 of the lower shell 1, the first part of the area between the pole ear side of the battery cell stack 2 and the lower shell 1 is formed as a glue filling area, and the second part of the area is formed as a gas exhaust area, and the first foam glue 31 is filled in the glue filling area; the high temperature resistant element 5 is installed in the gas exhaust area and separates the pole ears of the plurality of soft-packed batteries 21, and the high temperature resistant element 5 cooperates with the first foam glue 31 to define a plurality of gas exhaust channels 6, the gas exhaust channels 6 correspond to the soft-packed batteries 21 and are suitable for being connected to the gas exhaust portion 131 when the soft-packed batteries 21 are exhausted.

[0036] Optionally, the exhaust portion 131 includes an exhaust hole, and the exhaust hole is covered with a high temperature resistant patch 8; when the soft-pack battery cell 21 is in a normal operating state, the high temperature resistant patch 8 covers the exhaust hole, and when the soft-pack battery cell 21 has thermal runaway, the high temperature smoke impacts the corresponding high temperature resistant patch 8 so that the high temperature resistant patch 8 is damaged, and the high temperature smoke enters the exhaust hole, while other high temperature resistant patches 8 can prevent the high temperature smoke entering the exhaust hole from flowing back from other exhaust holes to other soft-pack battery cells 21. Further, the high temperature resistant patch 8 includes a plastic sheet.

[0037] Optionally, the high temperature resistant element 5 includes a ceramic foam piece, which has properties such as high temperature resistance, heat insulation, insulation and flame retardancy, which is beneficial to reducing the risk of heat spread.

[0038] Optionally, the bottom side of the battery cell stack 2 is directly bonded and fixed to the bottom plate 11 of the lower shell 1 by means of a heat-conducting structural adhesive, so that the connection is stable and reliable, and the operation is simple and convenient.

[0039] Optionally, the upper cover 4 is located on the top side of the cell stack 2 and covers the lower shell 1 , or in other words, the upper cover 4 covers the upper opening of the lower shell 1 so that the cell stack 2 can be encapsulated in the accommodating space defined by the upper cover 4 and the lower shell 1 .

[0040] Optionally, in the length direction of the soft-pack battery 21, both ends of the soft-pack battery 21 have pole ears, and the side of the soft-pack battery 21 with the pole ear is the same side as the pole ear side of the battery stack 2. Among them, in the present application, the length direction of the soft-pack battery 21 is the same as the length direction of the battery stack 2, that is, the X direction in the accompanying drawings; the thickness direction of the soft-pack battery 21, the stacking direction of multiple soft-pack batteries 21 in the same battery stack 2, and the width direction of the battery stack 2 are the same, that is, the Y direction in the accompanying drawings; the height direction of the soft-pack battery 21, the height direction of the pole ear of the soft-pack battery 21, the height direction of the pole ear side of the battery stack 2, the height direction of the battery stack 2, and the height direction of the lower shell 1 are the same, that is, the Z direction in the accompanying drawings.

[0041] In the battery pack of the above-mentioned embodiment, the cell stack 2 is connected and fixed to the lower shell 1, which is beneficial to improving the installation stability of the cell stack 2, especially the bottom side of the cell stack 2 is directly connected to the lower shell 1, and the first foam glue 31 is filled between the pole ear side of the cell stack 2 and the lower shell 1. The cell stack 2 has good structural stability, which is beneficial to prevent the pole ear side of the cell stack 2 from colliding during transportation or vibration and causing a short circuit; in addition, a part of the area between the pole ear side of the cell stack 2 and the lower shell 1 is installed with a high-temperature resistant element 5, so that the high-temperature flue gas can be quickly discharged from the vicinity of the pole ear of the soft-pack battery 21, thereby improving the exhaust efficiency, and the pole ears of adjacent soft-pack battery cells 21 are separated by the high-temperature resistant element 5 and cooperated with the first foam glue 31 to define a plurality of partitioned exhaust channels 6, so that each soft-pack battery cell 21 has an exhaust channel 6 corresponding to it and capable of exhausting independently, which is beneficial to reducing the risk of heat spread and short circuit of the soft-pack battery cell 21, thereby helping to improve the safety performance of the battery pack.

[0042] See also Figure 2 , Figures 4 to 6 In some optional embodiments, the glue filling area and the exhaust area are distributed along the height direction of the battery cell stack 2, and the exhaust area is located between the upper cover 4 and the glue filling area, that is, the high temperature resistant component 5 is located between the upper cover 4 and the first foam glue 31. The exhaust area is located between the upper cover 4 and the glue filling area, or in other words, the exhaust area is located above the glue filling area. On the one hand, it is convenient to install the high temperature resistant component 5, and on the other hand, the high temperature smoke can enter the exhaust area after being discharged from the soft-pack battery cell 21 and flows upward, so that the exhaust is smoother.

[0043] See also Figure 2 , Figures 4 to 6 In some optional embodiments, in the height direction of the battery cell stack 2, the distance between the top of the pole ear of the soft-pack battery cell 21 and the bottom plate 11 is H1, the distance between the top of the first foam glue 31 and the bottom plate 11 is H2, H1≤H2, and the first foam glue 31 covers the pole ear of the soft-pack battery cell 21, that is, the height of the first foam glue 31 is not lower than the height of the pole ear of the soft-pack battery cell 21, and the first foam glue 31 completely covers the pole ear of the soft-pack battery cell 21 to prevent the pole ear of the soft-pack battery cell 21 from being exposed.

[0044] In the battery pack of the above embodiment, the first foam glue 31 is filled to a suitable height and completely covers the tabs of the soft-pack battery cell 21, thereby preventing the tabs of the soft-pack battery cell 21 from being exposed and ensuring the structural strength, stability and exhaust effect.

[0045] See also Figure 2 , Figures 4 to 10In some optional embodiments, the high temperature resistant element 5 includes a main body 51 and a plurality of isolating parts 52 spaced apart along the stacking direction of the soft-pack battery cells 21, one end of the isolating part 52 is connected to the side of the main body 51 facing the first foam glue 31, and the other end of the isolating part 52 extends between the tabs of two adjacent soft-pack battery cells 21 and adheres to the first foam glue 31. It can be understood that the isolating part 52 is not limited to separating two adjacent soft-pack battery cells 21, or in other words, the arrangement of one soft-pack battery cell 21 between two adjacent isolating parts 52 is not limited, and two or more soft-pack battery cells 21 can be arranged between two adjacent isolating parts 52, and the specific number can be set according to needs.

[0046] Optionally, the side of the main body 51 facing away from the first foam glue 31 is in contact with the upper cover 4, that is, the side of the main body 51 facing the upper cover 4 is in contact with the upper cover 4. Further, the side of the main body 51 facing the upper cover 4 is interference fit with the upper cover 4, which is conducive to improving the sealing between the main body 51 and the upper cover 4, wherein the main body 51 and the upper cover 4 can be bonded and fixed.

[0047] Optionally, the thickness of the isolation portion 52 gradually decreases from the end away from the exhaust portion 131 to the end close to the exhaust portion 131, that is, the width of the exhaust channel 6 gradually increases from the end away from the exhaust portion 131 to the end close to the exhaust portion 131, which facilitates the flow of high-temperature flue gas to a position close to the exhaust portion 131, which is conducive to efficient exhaust.

[0048] In the battery pack of the above embodiment, the high temperature resistant element 5 has a simple structure and can simultaneously separate the tabs of multiple soft-pack battery cells 21 from each other. The installation is quick and convenient, which not only improves the assembly efficiency but also reduces the risk of short circuit of the soft-pack battery cells 21.

[0049] See also Figure 2 , Figures 4 to 6 and Fig. 9 In some optional embodiments, the lower shell 1 includes an end beam 13, an exhaust bin 132 is provided in the end beam 13, and an explosion-proof valve 7 suitable for exhausting the exhaust bin 132 is installed on the end beam 13, and the explosion-proof valve 7 can be opened to discharge high-temperature flue gas when thermal runaway occurs; the pole ear side of the battery cell stack 2 includes a first pole ear side facing the end beam 13, the exhaust channel 6 is located on the first pole ear side of the battery cell stack 2, and the exhaust part 131 is arranged on the end beam 13 to connect the exhaust channel 6 and the exhaust bin 132.

[0050] Optionally, the number of the battery cell stacks 2 is two, the lower housing 1 further includes an intermediate beam 14 located between the two battery cell stacks 2, the pole ear side of the battery cell stack 2 further includes a second pole ear side facing the intermediate beam 14, and the second pole ear side of the battery cell stack 2 and the intermediate beam 14 are filled with a second foam glue 32. Further, the second foam glue 32 fills the area between the second pole ear side of the battery cell stack 2 and the intermediate beam 14, that is, the area between the second pole ear side of the battery cell stack 2 and the intermediate beam 14 is completely filled with the second foam glue 32, which is not only conducive to improving the structural stability and blocking the high-temperature flue gas from being discharged from the second pole ear side of the battery cell stack 2, but also the second foam glue 32 can separate the pole ears of multiple soft-pack batteries 21, which is conducive to reducing the risk of heat spread and short circuit at the pole ears.

[0051] Optionally, the end wall of the high temperature resistant element 5 facing the end beam 13 is tightly attached to and has an interference fit with the end beam 13. Further, the end wall of the main body 51 facing the end beam 13 is tightly attached to and has an interference fit with the end beam 13, and the end wall of the isolation part 52 facing the end beam 13 is tightly attached to and has an interference fit with the end beam 13, so that the sealing performance is good, and the high temperature flue gas is prevented from rushing to other exhaust passages 6.

[0052] Optionally, the lower shell 1 also includes side beams 12, the number of end beams 13 and side beams 12 is two, the end beams 13 and side beams 12 are alternately distributed and connected end to end to form a square frame, the bottom of the end beams 13 and side beams 12 are connected to the bottom plate 11 of the lower shell 1, the structure of the lower shell 1 is simple and stable, and can provide stable installation support for the battery cell stack 2.

[0053] In the battery pack of the above-mentioned embodiment, when thermal runaway occurs in the soft-pack battery cell 21, the high-temperature flue gas is discharged from the weak structure near the pole ear of the soft-pack battery cell 21 and flows through the exhaust channel 6 and the exhaust bin 132 in sequence, and then discharged from the exhaust bin 132 by the explosion-proof valve 7. The high-temperature flue gas is discharged smoothly, which is beneficial to reducing the risk of heat spread and short circuit.

[0054] In the battery pack of the utility model, a first foam glue 31 and a high temperature resistant element 5 are arranged between the ear side of the battery cell stack 2 and the lower shell 1. The first foam glue 31 and the high temperature resistant element 5 cooperate to limit the high temperature flue gas generated when thermal runaway occurs to the corresponding exhaust channel 6, so that the flow path of the high temperature flue gas is relatively independent, reducing the impact on other soft-pack battery cells 21, can effectively prevent short circuit and heat spread, and improve the safety performance of the battery pack.

[0055] In the description of this specification, the description with reference to the terms "this embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0056] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the technology may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed in the present invention shall still be covered by the claims of the present invention.

Claims

1. A battery pack, characterized in that: include: A lower housing having an exhaust portion; A battery cell stack, the battery cell stack comprising a plurality of stacked soft-pack battery cells, the battery cell stack being disposed in the lower shell, the bottom side of the battery cell stack being connected and fixed to the bottom plate of the lower shell, the first partial area between the tab side of the battery cell stack and the lower shell being formed as a glue filling area, and the second partial area being formed as an exhaust area; A first foam glue, wherein the first foam glue is filled in the glue pouring area; A high temperature resistant component is installed in the exhaust area and separates the tabs of the plurality of soft-pack batteries, and cooperates with the first foam glue to define a plurality of exhaust channels, wherein the exhaust channels correspond to the soft-pack batteries and are suitable for being connected to the exhaust part when the soft-pack batteries are exhausted.

2. The battery pack according to claim 1, characterized in that: The high temperature resistant element includes a main body and a plurality of isolation parts spaced apart along the stacking direction of the soft-pack battery cells, one end of the isolation part is connected to a side of the main body facing the first foam glue, and the other end of the isolation part extends between the pole ears of two adjacent soft-pack battery cells and adheres to the first foam glue.

3. The battery pack according to claim 2, characterized in that: It also includes an upper cover, which is located on the top side of the battery cell stack and covers the lower shell. The glue filling area and the exhaust area are distributed along the height direction of the battery cell stack, and the exhaust area is located between the upper cover and the glue filling area.

4. The battery pack according to claim 3, characterized in that: The side of the main body facing away from the first foam adhesive is in contact with the upper cover.

5. The battery pack according to claim 2, characterized in that: The thickness of the isolation portion gradually decreases from an end away from the exhaust portion to an end close to the exhaust portion.

6. The battery pack according to claim 1, characterized in that: The lower shell includes an end beam, an exhaust bin is provided in the end beam, and an explosion-proof valve suitable for exhausting the exhaust bin is installed on the end beam; the pole ear side of the battery cell stack includes a first pole ear side facing the end beam, the exhaust channel is located on the first pole ear side of the battery cell stack, and the exhaust part is arranged on the end beam to connect the exhaust channel and the exhaust bin.

7. The battery pack according to claim 6, characterized in that: The number of the battery cell stacks is two, the lower shell further includes a middle beam located between the two battery cell stacks, the pole ear side of the battery cell stack further includes a second pole ear side facing the middle beam, and a second foamed glue is filled between the second pole ear side of the battery cell stack and the middle beam.

8. The battery pack according to claim 6, characterized in that: The end wall of the high temperature resistant element facing the end beam is in close contact with the end beam and has an interference fit.

9. The battery pack according to any one of claims 1 to 8, characterized in that: The exhaust portion comprises an exhaust hole, and the exhaust hole is covered with a high temperature resistant patch.

10. The battery pack according to any one of claims 1 to 8, characterized in that: The high temperature resistant element comprises a ceramic foam piece.

11. The battery pack according to any one of claims 1 to 8, characterized in that: The bottom side of the battery cell stack is directly bonded and fixed to the bottom plate of the lower shell by means of a heat-conducting structural adhesive.

12. The battery pack according to any one of claims 1 to 8, characterized in that: In the height direction of the battery cell stack, the distance between the top of the tab of the soft-pack battery cell and the bottom plate is H1, the distance between the top of the first foam glue and the bottom plate is H2, H1≤H2, and the first foam glue covers the tab of the soft-pack battery cell.

Images