Reinforced battery shell and lithium battery

Abstract

The utility model discloses a reinforced battery shell and a lithium battery, and belongs to the technical field of lithium batteries, the reinforced battery shell comprises an explosion-proof hole, the explosion-proof hole penetrates through one side plate of the shell, the side plate comprises a first plane and a second plane which are oppositely arranged, and the second plane is arranged towards a battery cell; the second plane is provided with a reinforcing ring on the periphery of the explosion-proof hole, and the reinforcing ring protrudes in the direction away from the second plane; at least one air guide groove is formed in the reinforcing ring, and the air guide groove is communicated with the anti-explosion hole; and the second plane is provided with a plurality of reinforcing ribs on the outer side of the reinforcing ring. The protruding structure of the reinforcing ring can enable a gap to be reserved between the explosion-proof hole and the battery cell when the battery cell expands and displaces, the battery cell is prevented from blocking the explosion-proof hole, the gas release efficiency is guaranteed, and the gas guide groove can further guide gas from the interior of the shell to the explosion-proof hole to be released.

Description

A reinforced battery casing and lithium battery Technical Field

[0001] This utility model relates to the field of lithium battery technology, specifically to a reinforced battery casing and a lithium battery. Background Technology

[0002] The casing is a crucial component of a battery, typically housing stacked or wound cells. When a cell experiences thermal runaway, the bare cells inside can easily shift or expand and deform with the airflow generated by the runaway, clogging the explosion-proof valve and affecting the battery's reliability under extreme conditions.

[0003] To improve battery reliability, existing technologies, such as Chinese patent document CN116557596A, disclose an explosion-proof valve, end cap assembly, battery, and energy storage device. In this invention, reinforcing ribs are arranged at intervals around the weak part of the explosion-proof valve, and connecting ribs are connected between the reinforcing ribs and the edge of the weak part. The reinforcing ribs and connecting ribs can increase the structural strength of the explosion-proof valve.

[0004] However, when a bare cell shifts or expands due to thermal runaway, it can compress the end cap or housing. Explosion-proof valves, as safety components of the battery, are typically installed on the end cap or housing, which are equipped with corresponding explosion-proof holes. When a bare cell compresses the end cap or housing, these explosion-proof holes become blocked, hindering the release of thermal runaway gas. Summary of the Invention

[0005] The purpose of this invention is to provide a reinforced battery casing and lithium battery, which solves the problem in the prior art where, when a bare cell shifts or expands due to thermal runaway, the bare cell presses against the end cap or casing, causing the explosion-proof hole to be blocked and affecting the release of thermal runaway airflow.

[0006] To achieve the above objectives, this utility model provides a reinforced battery casing, including an explosion-proof hole. The explosion-proof hole is disposed through a side plate of the casing. The side plate includes a first plane and a second plane disposed opposite to each other, with the second plane facing the battery cell. A reinforcing ring is disposed on the outer periphery of the explosion-proof hole on the second plane, and the reinforcing ring protrudes in a direction away from the second plane. The reinforcing ring has at least one vent groove, which communicates with the explosion-proof hole. Several reinforcing ribs are disposed on the outer side of the reinforcing ring on the second plane.

[0007] Furthermore, the protrusion height of the reinforcing ring is less than or equal to the protrusion height of the reinforcing rib.

[0008] The protrusion height of the reinforcing ring is smaller than that of the reinforcing rib. When the battery cell expands or shifts, it will preferentially contact the reinforcing rib around the reinforcing ring, thus maintaining a gap between the reinforcing ring and the battery cell. This can minimize the battery cell's contact with the reinforcing ring or even the explosion-proof hole, thereby improving the gas release efficiency.

[0009] Furthermore, the end of the reinforcing rib may or may not be connected to the outer periphery of the reinforcing ring.

[0010] When the ends of the reinforcing ribs are connected to the outer periphery of the reinforcing ring, the structural strength of the reinforcing ring can be increased, reducing the risk of deformation. When the ends of the reinforcing ribs are not connected to the outer periphery of the reinforcing ring, the space around the reinforcing ring can be increased, improving gas release efficiency.

[0011] Furthermore, the reinforcing rib includes a first rib and a second rib, which are cross-connected.

[0012] The cross arrangement ensures that the stiffeners are evenly stressed in multiple directions, avoiding localized stress concentration or deformation of unidirectional stiffeners due to changes in load direction.

[0013] Furthermore, the first and second ribs may intersect perpendicularly or not perpendicularly.

[0014] When the first and second ribs intersect perpendicularly, loads can be evenly distributed in all directions, making it suitable for uniformly distributed loads. Right-angle connections simplify design, manufacturing, and installation, reducing processing errors. When the first and second ribs do not intersect perpendicularly, the non-orthogonal layout enhances the torsional stiffness of the shell, making it suitable for structures susceptible to torsional or shear loads.

[0015] Furthermore, a third rib connects the first and second ribs, and the third rib, together with the first and second ribs, forms a triangular reinforcing structure. Through the triangular effect, the shell's compressive strength and deformation resistance can be greatly increased.

[0016] Furthermore, two gas guide channels are provided, symmetrically arranged about the center of the explosion-proof hole. These two channels allow gas inside the casing to be guided into the explosion-proof hole from two opposite directions, further improving gas release efficiency.

[0017] Furthermore, the depth of the air guide groove is less than or equal to the protrusion height of the reinforcing ring.

[0018] When the depth of the gas guide groove is equal to the protrusion height of the reinforcing ring, the gas guide groove completely penetrates the side wall of the reinforcing ring to form a completely broken section, which can increase the gas passage area of ​​the gas guide groove and improve the gas guide efficiency.

[0019] Furthermore, a welding part is provided around the outer periphery of the first plane surrounding the explosion-proof hole, and the welding part is a sinking structure.

[0020] The submerged structure constrains the welding position, resulting in more uniform and controllable welds, reducing defects such as incomplete welds or burn-through, and improving the yield rate. Under extreme operating conditions, the submerged structure can prevent the explosion-proof valve from falling off or shifting, ensuring that the pressure relief process is controllable.

[0021] This utility model also provides a lithium battery, including the aforementioned reinforced battery casing.

[0022] Compared with existing known technologies, the technical solution provided by this utility model has the following beneficial effects:

[0023] This invention provides a reinforced battery casing. The reinforcing ring significantly improves the strength and rigidity of the area surrounding the explosion-proof hole without increasing the overall wall thickness of the side plates of the battery casing. The protruding structure of the reinforcing ring creates a gap between the explosion-proof hole and the battery cell during cell expansion and displacement, preventing the cell from clogging the explosion-proof hole and ensuring efficient gas release. The gas guide groove further guides gas from inside the casing to the explosion-proof hole for release. The reinforcing ribs increase the structural strength of the casing and also prevent cell expansion and displacement, blocking the cells around the explosion-proof hole from moving towards it, further reducing the probability of blockage.

[0024] It is obvious that the elements or features described in the above individual embodiments can be used alone or in combination in other embodiments. Attached Figure Description

[0025] The dimensions and scales in the accompanying drawings do not represent the dimensions and scales of the actual product. The drawings are for illustrative purposes only, and some non-essential elements or features have been omitted for clarity.

[0026] Figure 1 is a schematic diagram of the battery casing in an embodiment of the present invention;

[0027] Figure 2 is a projection of the battery casing in the Y direction in Figure 1;

[0028] Figure 3 is a schematic cross-sectional view of section AA in Figure 2;

[0029] Figure 4 is a schematic diagram of the reinforcing rib structure in one embodiment of this utility model;

[0030] Figure 5 is a schematic diagram of the reinforcing rib structure in an embodiment of this utility model (II);

[0031] Figure 6 is a schematic diagram of the reinforcing rib in an embodiment of this utility model (III).

[0032] Explanation of reference numerals in the attached figures

[0033] 100. Side plate; 101. First plane; 102. Second plane; 110. Explosion-proof hole; 120. Reinforcing ring; 121. Air guide groove; 130. First rib; 140. Second rib; 150. Third rib; 160. Welded part. Detailed Implementation

[0034] The present invention will now be described in detail with reference to the accompanying drawings. The embodiments described herein are merely preferred embodiments of the present invention. Those skilled in the art can conceive of other ways to implement the present invention based on the preferred embodiments, and such other ways also fall within the scope of the present invention.

[0035] Referring to Figures 1-6, an embodiment of this application provides a reinforced battery casing, including multiple integrally formed side plates 100. The battery casing is used to house the battery cells and injected electrolyte. To promptly release the internal pressure of the casing in the event of thermal runaway, an explosion-proof valve is typically installed on the battery casing or top cover. This valve opens to release pressure when the internal pressure suddenly increases, reducing the risk of battery explosion. However, when the explosion-proof valve is installed on the top cover, during battery thermal runaway, the expansion or displacement of the battery cells may directly block the valve, preventing timely gas discharge and potentially causing an explosion. Therefore, in this embodiment, an explosion-proof hole 110 is provided on one side plate 100 of the battery casing. The explosion-proof hole 110 penetrates the side plate 100 of the casing. When the explosion-proof valve is installed on the side of the battery casing through the explosion-proof hole 110, the gas discharge channel is relatively wider and less prone to blockage by battery cell displacement or other components. The side plate 100 includes a first plane 101 and a second plane 102 disposed opposite to each other, with the second plane 102 facing the battery cell; that is, the first plane 101 is the outer surface, and the second plane 102 is the inner surface. A reinforcing ring 120 is provided on the outer periphery of the explosion-proof hole 110 on the second plane 102, and the reinforcing ring 120 protrudes away from the second plane 102. The reinforcing ring 120 significantly improves the strength and rigidity of the area surrounding the explosion-proof hole 110 without increasing the overall wall thickness of the side plate 100 of the battery casing. The protruding structure of the reinforcing ring 120 allows a gap to be maintained between the explosion-proof hole 110 and the battery cell when the battery cell expands and shifts, preventing the battery cell from blocking the explosion-proof hole 110 and ensuring efficient gas release. A venting groove 121 is formed in the reinforcing ring 120, which communicates with the explosion-proof hole 110. The venting groove 121 can further guide gas from inside the shell to the explosion-proof hole 110 for release. The second plane 102 is provided with several reinforcing ribs on the outer side of the reinforcing ring 120. The reinforcing ribs can increase the structural strength of the shell and prevent the expansion and displacement of the battery cells, thus preventing the battery cells around the explosion-proof hole 110 from moving towards the explosion-proof hole 110 and further reducing the probability of the explosion-proof hole 110 becoming blocked.

[0036] It should be noted that the number of gas guide grooves 121 is not limited to one. In some embodiments of this application, as shown in Figure 3, two gas guide grooves 121 are provided, and the two gas guide grooves 121 are symmetrically arranged about the center of the explosion-proof hole 110. The two gas guide grooves 121 can guide the gas inside the shell into the location of the explosion-proof hole 110 from two opposite directions, further improving the gas release efficiency. Of course, the number of gas guide grooves 121 can be more, such as three or four. The number of gas guide grooves 121 is determined according to factors such as the size of the reinforcing ring 120 and the structural strength, ensuring both structural strength and gas guiding efficiency.

[0037] Understandably, the depth of the gas guide groove 121 is less than or equal to the protrusion height of the reinforcing ring 120. When the depth of the gas guide groove 121 is equal to the protrusion height of the reinforcing ring 120, the gas guide groove 121 completely penetrates the side wall of the reinforcing ring 120, forming a completely disconnected fracture, which can increase the gas passage area of ​​the gas guide groove 121 and improve the gas guiding efficiency. When the depth of the gas guide groove 121 is less than the protrusion height of the reinforcing ring 120, the gas guide groove 121 partially penetrates the side wall of the reinforcing ring 120, forming a partially disconnected fracture, which improves the structural strength of the reinforcing ring 120 while ensuring that the reinforcing ring 120 has the ability to guide gas.

[0038] In some embodiments, the protrusion height of the reinforcing ring 120 is less than or equal to the protrusion height of the reinforcing rib. Preferably, the protrusion height of the reinforcing ring 120 is less than the protrusion height of the reinforcing rib, so that when the battery cell expands or shifts, it preferentially contacts the reinforcing rib around the reinforcing ring 120, thereby maintaining a gap between the reinforcing ring 120 and the battery cell. This can minimize the battery cell's contact with the reinforcing ring 120 or even with the explosion-proof hole 110, thereby improving the gas release efficiency.

[0039] Furthermore, as shown in Figure 3, the ends of the reinforcing ribs may or may not be connected to the outer periphery of the reinforcing ring 120. When the ends of the reinforcing ribs are connected to the outer periphery of the reinforcing ring 120, the structural strength of the reinforcing ring 120 can be increased, reducing the risk of deformation. When the ends of the reinforcing ribs are not connected to the outer periphery of the reinforcing ring 120, the space around the reinforcing ring 120 can be increased, improving gas release efficiency.

[0040] Specifically, as shown in Figures 3, 4, and 5, the stiffener includes a first stiffener 130 and a second stiffener 140, which are intersected. This intersecting arrangement ensures that the stiffener structure is subjected to uniform stress in multiple directions, avoiding localized stress concentration or deformation of the unidirectional stiffener due to changes in load direction. Furthermore, the first stiffener 130 and the second stiffener 140 can intersect perpendicularly or non-perpendicularly. When the first stiffener 130 and the second stiffener 140 intersect perpendicularly, they can uniformly transfer loads in all directions, suitable for uniformly distributed loads. Right-angle connections simplify design, manufacturing, and installation, reducing processing errors. When the first stiffener 130 and the second stiffener 140 do not intersect perpendicularly, the non-orthogonal layout enhances the torsional stiffness of the shell, suitable for structures susceptible to torsional or shear loads.

[0041] In some embodiments, as shown in FIG6, a third rib 150 is connected between the first rib 130 and the second rib 140. The third rib 150, together with the first rib 130 and the second rib 140, forms a triangular reinforcing structure. The triangular effect can significantly increase the shell's compressive strength and deformation resistance.

[0042] Understandably, the explosion-proof valve needs to be installed at the corresponding position of the explosion-proof hole 110, as shown in Figure 1. A welding section 160 is provided around the outer periphery of the first plane 101 surrounding the explosion-proof hole 110. The welding section 160 has a recessed structure. The recessed structure constrains the welding position, making the weld more uniform and controllable, reducing defects such as incomplete welds or burn-through, and improving the yield rate. The supporting effect of the recessed structure and the increased welding area together enhance the overall load-bearing capacity of the structure, optimize stress distribution and sealing performance, and extend the service life of the explosion-proof valve and battery housing. Moreover, under extreme operating conditions, the recessed structure can prevent the explosion-proof valve from falling off or shifting, ensuring that the pressure relief process is controllable.

[0043] Another aspect of this application provides a lithium battery, including the aforementioned reinforced battery casing.

[0044] In the description of this utility model, it should be noted that the terms "front," "rear," "left," "right," "upper," "lower," "top," "bottom," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this utility model. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0045] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0046] The scope of protection of this utility model is defined only by the claims. Thanks to the teachings of this utility model, those skilled in the art will readily recognize that alternative structures to the disclosed structure can be used as feasible alternative implementations, and that the disclosed implementations can be combined to produce new implementations, which also fall within the scope of the appended claims.

Claims

1. A reinforced battery casing, comprising an explosion-proof hole (110) penetrating a side plate (100) of the casing, the side plate (100) comprising a first plane (101) and a second plane (102) disposed opposite to each other, the second plane (102) facing the battery cell; characterized in that, The second plane (102) has a reinforcing ring (120) on the outer periphery of the explosion-proof hole (110), the reinforcing ring (120) protruding away from the second plane (102); the reinforcing ring (120) has at least one air guide groove (121) which is connected to the explosion-proof hole (110); the second plane (102) has several reinforcing ribs on the outer side of the reinforcing ring (120).

2. The reinforced battery casing according to claim 1, characterized in that, The protrusion height of the reinforcing ring (120) is less than or equal to the protrusion height of the reinforcing rib.

3. The reinforced battery case of claim 1, wherein The end of the reinforcing rib is connected to or not connected to the outer periphery of the reinforcing ring (120).

4. A reinforced battery casing according to claim 3, characterized in that, The reinforcing rib includes a first rib (130) and a second rib (140), which are cross-connected.

5. A reinforced battery casing according to claim 4, characterized in that, The first rib (130) and the second rib (140) intersect perpendicularly or not perpendicularly.

6. A reinforced battery casing according to claim 4, characterized in that, A third rib (150) is connected between the first rib (130) and the second rib (140), and the third rib (150) forms a triangular reinforcing structure with the first rib (130) and the second rib (140).

7. The reinforced battery case of claim 1, wherein There are two air guide grooves (121), and the two air guide grooves (121) are symmetrically arranged about the center of the explosion-proof hole (110).

8. The reinforced battery case of claim 1, wherein, The depth of the air guide groove (121) is less than or equal to the protrusion height of the reinforcing ring (120).

9. The reinforced battery case of claim 1, wherein, The first plane (101) is provided with a welding part (160) around the outer periphery of the explosion-proof hole (110), and the welding part (160) is a sinking structure.

10. A lithium battery, characterized by, Includes the reinforced battery casing as described in any one of claims 1-9.

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