Side plate for battery cell and battery cell

Abstract

The utility model provides a side plate for a battery cell and the battery cell, the side plate for the battery cell is arranged on one side of a pole group, the side plate comprises a main body, the main body is provided with a through hole arranged corresponding to an anti-explosion valve mounting hole on a battery cell shell and a weak part arranged in the through hole, and the weak part is arranged along with the through hole; a plurality of first through holes are formed in the weak part in a penetrating manner, a plurality of connecting ribs for connecting the weak part and the inner peripheral wall of the through hole are arranged between the outer peripheral wall of the weak part and the inner peripheral wall of the through hole, second through holes are formed among the two adjacent connecting ribs, the weak part and the main body, and the connecting ribs can be heated and fused when the battery cell is in thermal runaway. According to the side plate for the battery cell disclosed by the utility model, the weak part in the through hole is connected with the main body through the plurality of connecting ribs, the explosion-proof valve can be protected through the first vent holes in the weak part, and the vent area at the through hole can be increased by fusing the connecting ribs when thermal runaway occurs in the battery cell; therefore, the pressure relief efficiency of the anti-explosion valve is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of power batteries, and in particular to a side plate for a battery cell. At the same time, the utility model also relates to a battery cell provided with the side plate for the battery cell. Background Art

[0002] Thermal runaway of a battery cell refers to the phenomenon that during the charging and discharging process of a battery cell, the heat generated inside cannot be dissipated in time, causing the temperature of the battery cell to rise rapidly, which may eventually cause combustion or explosion. Thermal runaway of a battery cell refers to the phenomenon that the temperature of the battery cell rises uncontrollably due to the chain reaction of heat release from the battery cell. The causes of thermal runaway include short circuit of the power battery, excessive charging power, reduced battery discharge capacity, over-discharge, external force collision, and internal short circuit.

[0003] In the prior art, a side plate is usually provided between the bottom side of the pole group and the battery cell housing, and a pressure relief hole is provided on the side plate corresponding to the explosion-proof valve on the battery cell housing. However, when the battery cell has thermal runaway, the pressure relief capacity of the pressure relief hole is limited, which is not conducive to the pressure relief of the battery cell, and thus is not conducive to the safety of the battery cell. Therefore, how to optimize the side plate to improve the pressure relief efficiency when the battery cell has thermal runaway has become a research direction for those skilled in the art. Utility Model Content

[0004] In view of this, the utility model aims to provide a side plate for a battery cell, so as to improve the performance of an explosion-proof valve when the battery cell is in thermal runaway.

[0005] In order to achieve the above object, the technical solution of the utility model is implemented as follows:

[0006] A side plate for a battery cell, arranged on one side of an electrode group, the side plate comprising a main body, the main body being provided with a through hole arranged corresponding to the explosion-proof valve mounting hole on the battery cell housing, and a weak portion arranged in the through hole;

[0007] The weak portion is provided with a plurality of first ventilation holes which are arranged through-through, and a plurality of connecting ribs which connect the outer circumferential wall of the weak portion and the inner circumferential wall of the through hole are provided between the two, a second ventilation hole is formed between two adjacent connecting ribs, the weak portion and the main body, and the connecting ribs can be heated and melted when the battery cell has thermal runaway.

[0008] Furthermore, both sides of the body in the width direction are provided with support protrusions extending along the length direction of the body, and the two support protrusions can abut against the inner wall of the battery cell shell to define an air passage between the body and the battery cell shell.

[0009] Furthermore, the main body is provided with a plurality of third ventilation holes which are arranged through-through; and / or, a height H of the supporting protrusion satisfies: 0.5 mm<H<10 mm.

[0010] Furthermore, the area of ​​the first ventilation hole is smaller than the area of ​​the third ventilation hole.

[0011] Furthermore, the free end of the supporting protrusion is provided with an inclined guiding surface, and the guiding surface is used to guide the main body to be installed into the battery cell housing.

[0012] Furthermore, an included angle α between the guide surface and the main body satisfies: 5°<α<90°.

[0013] Furthermore, the thickness L of the support protrusion is 1 Satisfy: 1mm<L 1 <6mm; and / or, the minimum distance L between the projection contour line of the explosion-proof valve mounting hole on the main body and the supporting protrusion 2 Satisfy: 0.1mm<L 2 <10mm.

[0014] Furthermore, the length L of the connecting rib is 3 Satisfy: 0.15mm<L 3 <0.5mm, the width W of the connecting rib satisfies: 0.5mm<W<8mm; and / or the thickness L of the connecting rib 4 Satisfy: 0.3mm<L 4 <1mm.

[0015] Furthermore, the total area S of the first vent holes on the weak portion is 1 The weak part area S 2 The ratio A between them satisfies: A≥0.1.

[0016] Compared with the prior art, the utility model has the following advantages:

[0017] The side plate for the battery cell described in the utility model is provided with a through hole corresponding to the installation hole of the explosion-proof valve on the main body, and a plurality of first vent holes are provided on the weak portion in the through hole, and is connected to the main body through a plurality of connecting ribs. Not only can the protection effect of the explosion-proof valve be improved through the first vent holes on the weak portion, but also when thermal runaway occurs inside the battery cell, the ventilation area at the through hole can be increased by fusing the connecting ribs, thereby facilitating the improvement of the pressure relief efficiency of the explosion-proof valve, and further facilitating the improvement of the safety of the battery cell.

[0018] In addition, by providing two supporting protrusions on the main body, and the supporting protrusions define an air passage between the main body and the battery cell shell, it is beneficial to improve the exhaust efficiency of the gas in the battery cell. The provision of the third vent is beneficial to cooperate with the first vent to discharge the hot gas generated by thermal runaway of the battery cell to the outside; the provision of the height range of the supporting protrusion is not only beneficial to ensure the performance of the air passage, but also beneficial to reduce the space occupied inside the battery cell. The area of ​​the first vent is smaller than the area of ​​the third vent, which is beneficial to improve the protection effect of the explosion-proof valve. By providing a guide surface on the supporting protrusion, it is beneficial to guide the main body to be inserted into the battery cell shell along with the pole group, thereby improving the assembly efficiency, and at the same time preventing damage to the pole group. The determination of the angle range between the guiding surface and the main body is beneficial to ensure the guiding effect of the guiding surface.

[0019] In addition, the determination of the thickness range of the support protrusion is conducive to ensuring the support effect of the electrode group; the setting of the minimum distance range between the projection contour line of the explosion-proof valve installation hole on the main body and the support protrusion is conducive to improving the pressure relief efficiency of the explosion-proof valve. The setting of the length and width range of the connecting rib can also increase the ventilation area at the through hole by melting when the battery cell is in thermal runaway while meeting the connection requirements of the weak part; the setting of the thickness of the connecting rib is also conducive to ensuring the connection effect of the connecting rib and the melting effect during thermal runaway. The total area S of the first vent 1 and the weak part area S 2 The ratio between them is greater than or equal to 0.1, which is conducive to ensuring the pressure relief efficiency when the battery cell experiences thermal runaway.

[0020] In addition, another object of the present invention is to provide a battery cell, comprising a battery cell housing, a pole, and the battery cell side plate as described above.

[0021] The battery cell of the utility model is beneficial to improving the pressure relief efficiency of the battery cell when thermal runaway occurs by providing the above-mentioned battery cell side plate, thereby improving the safety of the battery cell. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The accompanying drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The illustrative embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation on the present invention. In the accompanying drawings:

[0023] Figure 1 This is a schematic diagram of the positional relationship among the side plate, the electrode group and the explosion-proof valve for the battery cell according to the embodiment of the utility model in the use state;

[0024] Figure 2 It is a schematic diagram of the positional relationship between the side plate for the battery cell and the explosion-proof valve according to an embodiment of the utility model in one state;

[0025] Figure 3A schematic diagram of the relationship between the side plate for the battery cell and the explosion-proof valve according to an embodiment of the utility model at another viewing angle;

[0026] Figure 4 This is a schematic structural diagram of a side plate for a battery cell according to an embodiment of the utility model;

[0027] Figure 5 for Figure 4 A top view of

[0028] Figure 6 for Figure 5 Schematic diagram of some structures in ;

[0029] Figure 7 for Figure 5 Left view of;

[0030] Figure 8 for Figure 5 AA direction section view in.

[0031] Description of reference numerals:

[0032] 1. Side plate; 2. Pole group; 3. Explosion-proof valve;

[0033] 101. Main body; 1011. Third ventilation hole; 102. Weak portion; 1021. First ventilation hole; 1022. Connecting rib; 103. Second ventilation hole; 104. Supporting protrusion; 1041. Guide surface. DETAILED DESCRIPTION

[0034] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other.

[0035] In the description of the present invention, it should be noted that if there are terms indicating orientation or positional relationship such as "upper", "lower", "inner", "back", etc., they are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, if there are terms such as "first", "second", etc., they are also used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0036] The present invention will be described in detail below with reference to the accompanying drawings and in combination with embodiments.

[0037] This embodiment relates to a side plate for a battery cell, such as Figures 1 to 3 As shown in FIG. 1 , the side plate 1 is arranged on one side of the electrode group 2. In terms of overall structure, as shown in FIG. Figure 4As shown in , the side plate 1 includes a main body 101, on which a through hole corresponding to the explosion-proof valve mounting hole on the battery cell housing is provided, and a weak portion 102 is provided in the through hole, and the weak portion 102 is provided in the shape of the through hole.

[0038] Among them, a plurality of first ventilation holes 1021 are provided on the weak part 102, and a plurality of connecting ribs 1022 are provided between the outer peripheral wall of the weak part 102 and the inner peripheral wall of the through hole to connect the two together, and a second ventilation hole 103 is formed between two adjacent connecting ribs 1022, the weak part 102 and the main body 101, and the connecting ribs 1022 can be heated and melted when the battery cell has thermal runaway.

[0039] The side plate for the battery cell described in this embodiment is provided with a through hole corresponding to the explosion-proof valve installation hole on the main body 101, and a plurality of first vent holes 1021 are provided on the weak portion 102 in the through hole, and is connected to the main body 101 through a plurality of connecting ribs 1022. Not only can the first vent holes 1021 on the weak portion 102 improve the protection effect of the explosion-proof valve 3, but also when thermal runaway occurs inside the battery cell, the ventilation area at the through hole can be increased by fusing the connecting ribs 1022, thereby facilitating the pressure relief efficiency of the explosion-proof valve 3 and further facilitating the safety of the battery cell.

[0040] In terms of specific structure, the side plate 1 is arranged between the bottom side of the electrode group 2 and the battery cell housing, and the explosion-proof valve 3 is installed at the explosion-proof valve installation hole and is spaced apart from the side plate 1 to discharge the hot gas inside the battery cell when thermal runaway occurs in the battery cell. In addition to preventing the diaphragm in the electrode group 2 from protruding and damaging the explosion-proof valve 3, the side plate 1 in this embodiment is conducive to improving the explosion-proof effect of the explosion-proof valve 3, and is also conducive to improving the stability of the electrode group 2 structure.

[0041] like Figure 4 As shown in the figure, the shape of the through hole matches the shape of the explosion-proof valve mounting hole, and both are oblong, and the weak portion 102 is also oblong. The outer peripheral wall of the weak portion 102 and the inner peripheral wall of the through hole are arranged at intervals. A plurality of connecting ribs 1022 are connected between the outer peripheral wall of the weak portion 102 and the inner peripheral wall of the through hole at intervals along the circumference of the weak portion 102. The second vent holes 103 located on both sides of the width direction of the weak portion 102 are in the shape of long strips, and the second vent holes 103 located at the ends of the weak portion 102 are in the shape of arcs.

[0042] The connecting rib 1022 in this embodiment can melt when the temperature inside the battery cell exceeds a preset temperature (that is, when thermal runaway occurs in the battery cell), and move outward under the action of the thermal runaway airflow, thereby increasing the exhaust area at the through hole, thereby facilitating the exhaust efficiency of the hot airflow generated by thermal runaway.

[0043] As a feasible implementation, the side panel 1 is integrally injection molded with materials such as PP or PE, and the main body 101 in the side panel 1 can be connected to the mylar film outside the electrode group 2 by hot melting and / or adhesive tape bonding. Here, the material of the side panel 1 and the connection method on the electrode group 2 have the advantages of being simple and easy to arrange and implement. At the same time, the thickness of the weak part 102 and the main body 101 are preferably relative, and the two can be preferably integrally molded to facilitate improving the connection strength and production efficiency of the two.

[0044] As a preferred implementation, in this embodiment, Figure 6 As shown in FIG. 1 , the length L of the connecting rib 1022 3 Satisfy: 0.15mm<L 3 <0.5mm, the width W of the connecting rib 1022 satisfies: 0.5mm<W<8mm. The length and width range of the connecting rib 1022 can meet the connection requirements of the weak part 102 and can also be melted when the battery cell is thermally runaway, thereby increasing the ventilation area at the through hole.

[0045] In specific implementation, the length L of the connecting rib 1022 3 The length L of the connecting rib 1022 may be 0.16 mm, 0.25 mm, 0.35 mm, 0.45 mm or 0.49 mm, etc. The width W of the connecting rib 1022 may be 0.51 mm, 1.5 mm, 2.5 mm, 3.5 mm, 4.5 mm, 5.5 mm, 6.5 mm, 7.5 mm or 7.9 mm, etc. 3 When the length L of the connecting rib 1022 is greater than 0.5 mm, and the width W of the connecting rib 1022 is greater than 8 mm, the connecting rib 1022 is not easy to melt when the battery cell is in thermal runaway, which is not conducive to ensuring the safety of thermal runaway. 3 When it is less than 0.15mm, and when the width W of the connecting rib 1022 is less than 0.5mm, the connection effect of the connecting rib 1022 is poor, and the connecting rib 1022 is prone to melt when the temperature in the battery cell rises but does not reach thermal runaway, which is not conducive to ensuring the safety of electrothermal runaway.

[0046] In addition, if Figure 8 As shown in FIG. 1 , the thickness L of the connecting rib 1022 is 4 Satisfy: 0.3mm<L 4 <1mm. The setting of the thickness of the connecting rib 1022 here is also conducive to ensuring the connection effect of the connecting rib 1022 and the fusing effect in case of thermal runaway. In specific implementation, the thickness L of the connecting rib 1022 is 4 It can be 0.31mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm or 0.99mm, etc. When the thickness L of the connecting rib 10224 When the thickness L of the connecting rib 1022 is less than or equal to 0.3 mm, the connection strength of the connecting rib 1022 is poor and it is easy to break before thermal runaway occurs, thus affecting the protective effect of the side panel 1. 4 When it is greater than or equal to 1 mm, the connecting rib 1022 is not easy to melt when thermal runaway occurs, which is not conducive to improving the pressure relief efficiency.

[0047] As a preferred embodiment, the total area S of the first vent holes 1021 on the weak portion 102 is 1 The area S of the weak portion 102 2 The ratio A between them satisfies: A≥0.1. Such a setting is conducive to ensuring the pressure relief efficiency when the battery cell is in thermal runaway. When the area ratio is implemented specifically, A can be 0.1, 0.15, 0.2, 0.3 or 0.4, etc. Among them, when the area ratio is less than 0.1, the ventilation area on the weak part 102 is small, which is not conducive to the discharge of the pressure in the battery cell.

[0048] like Figure 4 As shown in , the main body 101 is provided with a plurality of third vent holes 1011 which are arranged through. This is beneficial to cooperate with the first vent hole 1021 to discharge the hot air generated by the thermal runaway of the battery cell. The area of ​​the first vent hole 1021 is smaller than that of the third vent hole 1011. Such a setting is beneficial to improve the protection effect of the explosion-proof valve 3. For example Figure 4 As shown in , the first vent hole 1021 can be a circular hole, and the second vent hole 103 can be an oblong hole. Of course, the shapes of the first vent hole 1021 and the second vent hole 103 can also be determined according to the use requirements.

[0049] As a preferred embodiment, Figures 5 to 7 As shown in , both sides of the width direction of the main body 101 are provided with support protrusions 104 extending along the length direction of the main body 101, and the two support protrusions 104 can abut against the inner wall of the battery cell shell, and define a vent between the main body 101 and the battery cell shell. The two support protrusions 104 are provided, which can not only improve the exhaust efficiency of the gas in the battery cell by forming a vent, but also increase the distance between the pole group 2 and the explosion-proof valve 3, further improving the protection effect of the explosion-proof valve 3.

[0050] In specific implementation, in this embodiment, the height H of the support protrusion 104 satisfies: 0.5mm<H<10mm. It is not only beneficial to ensure the performance of the air duct, but also beneficial to reduce the space occupied inside the battery cell. In specific implementation, the height H of the support protrusion 104 may be 0.55mm, 2mm, 4mm, 6mm, 7mm, 8mm, 9mm or 9.5mm, etc. Among them, when the height H of the support protrusion 104 is less than or equal to 0.5mm, the specification of the air duct is small, which is not conducive to the discharge of hot air in the battery cell, and when the height H of the support protrusion 104 is greater than or equal to 10mm, it will occupy more internal space of the battery cell shell, affecting the energy density of the battery cell.

[0051] Further, such as Figure 4 As shown in the figure, the free end of the support protrusion 104 is provided with an inclined guide surface 1041, and the guide surface 1041 is used to guide the main body 101 to be installed into the battery cell housing. The guide surface 1041 is provided to facilitate guiding the main body 101 to be installed into the battery cell housing along with the electrode group 2, thereby facilitating the assembly efficiency and preventing the electrode group 2 from being damaged.

[0052] As a preferred arrangement, the guide surface 1041 is arranged at both ends of each supporting protrusion 104. The angle α between the guide surface 1041 and the main body 101 satisfies: 5°<α<90°. The determination of the angle range between the guide surface 1041 and the main body 101 is conducive to ensuring the guiding effect of the guide surface 1041. In specific implementation, the angle α can be: 6°, 20°, 30°, 40°, 50°, 60°, 70°, 80° or 89°, etc.

[0053] In addition, in this embodiment, Figure 8 As shown in FIG. 1 , the thickness L of the support protrusion 104 is 1 Satisfy: 1mm<L 1 <6mm, such a setting is conducive to ensuring the supporting effect of the electrode group 2 and the use effect of the airway. In specific implementation, the thickness L of the supporting protrusion 104 is 1 It can be 1.5mm, 2mm, 3mm, 4mm, 5mm, 5.5mm or 5.9mm, etc.

[0054] In addition, if Figure 3 As shown in FIG. 1 , the minimum distance L between the projection contour line of the explosion-proof valve mounting hole on the main body 101 and the supporting protrusion 104 is 2 Satisfy: 0.1mm<L 2 Such a setting is conducive to improving the pressure relief efficiency of the explosion-proof valve 3. In specific implementation, the minimum distance L2 can be 0.12mm, 2mm, 3mm, 4mm, 5mm, 6mm, 7mm, 8mm or 9.5mm.

[0055] The side plate for the battery cell of this embodiment connects the weak portion 102 to the main body 101 via the connecting rib 1022. The setting of various parameters of the connecting rib 1022 is conducive to ensuring the protective effect of the side plate 1 and improving the pressure relief effect during thermal runaway of the battery cell. By setting various parameter ranges of the supporting protrusion 104, it is conducive to ensuring the supporting effect of the side plate 1 and further improving the pressure relief efficiency during thermal runaway. The structure of the entire side plate 1 is simple and easy to arrange and implement.

[0056] In addition, the present embodiment also relates to a battery cell, comprising a battery cell shell, a pole, and a side plate for the battery cell as described above, wherein the side plate 1 is located between the bottom surface of the pole group 2 and the battery cell shell, and the explosion-proof valve 3 is arranged on the bottom surface of the battery cell shell and is arranged corresponding to the side plate 1.

[0057] The battery cell described in this embodiment is beneficial to improving the pressure relief efficiency of the battery cell during thermal runaway by providing the above-mentioned battery cell side plate, thereby improving the safety of the battery cell.

[0058] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A side plate for a battery cell, arranged on one side of an electrode group, characterized in that: The side plate includes a main body, the main body is provided with a through hole corresponding to the explosion-proof valve mounting hole on the battery cell housing, and a weak portion provided in the through hole, and the weak portion is provided in accordance with the through hole; The weak portion is provided with a plurality of first ventilation holes which are arranged through-through, and a plurality of connecting ribs which connect the outer circumferential wall of the weak portion and the inner circumferential wall of the through hole are provided between the two, a second ventilation hole is formed between two adjacent connecting ribs, the weak portion and the main body, and the connecting ribs can be heated and melted when the battery cell has thermal runaway.

2. The side plate for a battery cell according to claim 1, characterized in that: Both sides of the body in the width direction are provided with support protrusions extending along the length direction of the body, and the two support protrusions can abut against the inner wall of the battery cell shell to define an air passage between the body and the battery cell shell.

3. The side plate for a battery cell according to claim 2, characterized in that: The main body is provided with a plurality of third vent holes which are arranged through-through; and / or, The height H of the supporting protrusion satisfies: 0.5mm<H<10mm.

4. The side plate for a battery cell according to claim 3, characterized in that: An area of ​​the first ventilation hole is smaller than an area of ​​the third ventilation hole.

5. The side plate for a battery cell according to claim 2, characterized in that: The free end of the supporting protrusion is provided with an inclined guiding surface, and the guiding surface is used to guide the main body to be installed into the battery cell housing.

6. The side plate for a battery cell according to claim 5, characterized in that: An included angle α between the guide surface and the main body satisfies: 5°<α<90°.

7. The side plate for a battery cell according to claim 2, characterized in that: The thickness L1 of the supporting protrusion satisfies: 1mm<L1<6mm; and / or, A minimum distance L2 between a projection contour line of the explosion-proof valve mounting hole on the main body and the supporting protrusion satisfies: 0.1 mm<L2<10 mm.

8. The side plate for a battery cell according to claim 1, characterized in that: The length L3 of the connecting rib satisfies: 0.15 mm < L3 < 0.5 mm, and the width W of the connecting rib satisfies: 0.5 mm < W < 8 mm; and / or, The thickness L4 of the connecting rib satisfies: 0.3mm<L4<1mm.

9. The side plate for a battery cell according to any one of claims 1 to 8, characterized in that: A ratio A between a total area S1 of the first vent holes on the weak portion and an area S2 of the weak portion satisfies: A≥0.

1.

10. A battery cell, characterized in that: The invention comprises a battery cell shell, a pole and a side plate for the battery cell according to any one of claims 1 to 9.

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