Pressure relief structure of battery shell

Abstract

According to the pressure relief structure of the battery shell, in the structure, the battery shell is used for packaging a core package, and the battery shell is provided with an anti-explosion exhaust hole; the explosion-proof valve boss is arranged on the battery shell and surrounds the explosion-proof exhaust hole, the first-stage step surrounds the explosion-proof exhaust hole and protrudes in the direction away from the core package from the battery shell, and the second-stage step is arranged on the inner side of the first-stage step and is recessed in the direction close to the core package relative to the first-stage step; the reinforcing rib bracket is arranged above the explosion-proof exhaust hole and is connected with the second-stage step; one side, facing the core package, of the reinforcing rib bracket is provided with a first fracture groove for fracture under stress; the anti-explosion piece is laid on the anti-explosion exhaust hole and the second-stage step; the anti-explosion valve protection film is laid on the first step. The structure prevents the explosion-proof sheet from inwards breaking the valve when being impacted by external force, so that the safety of the battery is protected.

Description

Technical Field

[0001] The utility model relates to the technical field of lithium-ion batteries, in particular to a pressure relief structure of a battery shell. Background Art

[0002] With the rapid growth of lithium-ion battery applications in power and energy storage, the energy density of prismatic batteries is increasing, and the industry's safety requirements for lithium batteries are also increasing. To avoid the safety risks caused by thermal runaway of battery cells, explosion-proof valve exhaust structures are generally designed into the top cover or casing of the battery to directional discharge the high-temperature, high-pressure gases generated during thermal runaway. Existing battery casings lack a reinforced support structure on the inside of the explosion-proof disc at the bottom. When impacted by external forces, the explosion-proof valve breaks inward, causing the internal battery electrodes to be impacted by external metal forces and cause internal short circuits.

[0003] The above information disclosed in the background technology section is only used to enhance understanding of the background of the present invention and therefore may contain information that does not constitute the prior art known to ordinary technicians in this field. Utility Model Content

[0004] The purpose of the utility model is to provide a pressure relief structure for a battery shell to reduce the hazards of high-temperature and high-pressure gases generated when the battery cell is under thermal runaway. The exhaust direction is downward and opposite to the direction of the passenger compartment. A reinforcing rib support structure is provided at the exhaust port of the explosion-proof valve to prevent the explosion-proof disk from breaking inward when impacted by external force, thereby protecting the battery safety.

[0005] In order to achieve the above purpose, the present invention provides the following technical solutions:

[0006] A pressure relief structure of a battery housing of the utility model includes:

[0007] A battery housing, which is used to encapsulate the core pack, and the battery housing has explosion-proof exhaust holes;

[0008] An explosion-proof valve boss is provided on the battery housing and surrounds the explosion-proof exhaust hole. The explosion-proof valve boss includes:

[0009] A step surrounds the explosion-proof vent and protrudes from the battery housing in a direction away from the core pack.

[0010] a second step, which is provided inside the first step and is recessed relative to the first step toward the core package;

[0011] A reinforcing rib bracket is provided above the explosion-proof exhaust hole and connected to the secondary step, and a first fracture groove for fracture under stress is provided on a side of the reinforcing rib bracket facing the core package;

[0012] An explosion-proof plate, which is laid on the explosion-proof exhaust hole and the secondary step;

[0013] The explosion-proof valve protective film is laid on the first step.

[0014] In the pressure relief structure of the battery shell, a second fracture groove for fracture under stress is provided on the side of the explosion-proof plate facing the core package.

[0015] In the pressure relief structure of the battery casing, the second fracture groove surrounds the side of the secondary step away from the primary step.

[0016] In the pressure relief structure of the battery casing, the second fracture groove is an annular groove.

[0017] In the pressure relief structure of the battery casing, the upper surface of the reinforcing rib bracket is flush with the upper surface of the secondary step.

[0018] In the pressure relief structure of the battery shell, the reinforcing rib bracket is a cross-shaped, M-shaped, well-shaped, mesh-shaped or stripe-shaped structure.

[0019] In the pressure relief structure of the battery shell, the explosion-proof exhaust hole is an elliptical hole, and the first-level step and the second-level step are runway-type structures surrounding the elliptical hole.

[0020] In the pressure relief structure of the battery housing, the battery housing is a blade-shaped structure, an explosion-proof area is provided downward from the bottom of the battery housing, and the explosion-proof exhaust hole is located in the explosion-proof area.

[0021] In the pressure relief structure of the battery housing, a positive electrode bracket is provided at one end of the battery housing to cover the positive electrode top cover of the positive electrode bracket, and a negative electrode bracket is provided at the other end of the battery housing to cover the negative electrode top cover of the negative electrode bracket.

[0022] In the pressure relief structure of the battery casing, a core pack insulating sheet is provided between the battery casing and the core pack.

[0023] In the above technical solution, the utility model provides a pressure relief structure for a battery shell, which has the following beneficial effects: the pressure relief structure of the battery shell is provided with a reinforcing rib support structure at the exhaust port of the explosion-proof valve, which supports and strengthens the structural strength of the explosion-proof valve plate. This structure can reduce the damage and cracking caused by the explosion-proof valve when it is impacted by a small external force, resulting in leakage of the battery cell, thereby improving the reliability of the battery; it can also prevent the explosion-proof valve from breaking inward when it is impacted by a large impact, reduce the impact of metal foreign matter on the interior of the battery, avoid causing internal short circuits and fires in the battery, and thus improve the safety of the battery. When the explosion-proof plate is opened by the airflow inside the battery, the reinforcing rib support can be separated from the shell along with the airflow, without affecting the effective use area of ​​the explosion-proof valve exhaust channel. The bottom of the battery shell is provided with an explosion-proof area downward, and the exhaust direction is downward and opposite to the direction of the passenger compartment, reducing the harm to the passenger compartment caused by the high-temperature and high-pressure gas generated when the battery cell thermal runaway occurs. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments recorded in the present invention. For ordinary technicians in this field, other drawings can also be obtained based on these drawings.

[0025] Figure 1 This is a schematic diagram of the exploded structure of the pressure relief structure of the battery housing of the present invention.

[0026] Figure 2 It is a schematic diagram of the three-dimensional structure of the pressure relief structure of the battery housing of the present invention.

[0027] Figure 3 for Figure 2 An enlarged schematic diagram of point B.

[0028] Figure 4 It is a side view schematic diagram of the pressure relief structure of the battery housing of the present invention.

[0029] Figure 5 for Figure 4 Enlarged schematic diagram of point F.

[0030] The markings in the accompanying drawings are: battery case 1, core pack 2, positive electrode top cover 3, negative electrode top cover 4, core pack insulating sheet 5, explosion-proof valve boss 6, reinforcing rib bracket 7, explosion-proof sheet 8, explosion-proof valve protective film 9, first fracture groove 10, first step 11, and second step 12. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical solutions and advantages of the implementation methods of the present invention clearer, the technical solutions in the implementation methods of the present invention will be clearly and completely described below in combination with the drawings in the implementation methods of the present invention. Obviously, the described implementation methods are only part of the implementation methods of the present invention, not all of the implementation methods.

[0032] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but rather merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by a person of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0033] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not need to be further defined or explained in subsequent drawings.

[0034] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings.

[0035] like Figure 1-5 As shown, in one embodiment, a pressure relief structure of a battery housing of the present invention includes:

[0036] A battery housing 1, which is used to encapsulate the core pack 2, and the battery housing 1 has an explosion-proof exhaust hole;

[0037] The explosion-proof valve boss 6 is provided on the battery housing 1 and surrounds the explosion-proof exhaust hole. The explosion-proof valve boss 6 includes:

[0038] A step surrounds the explosion-proof vent and protrudes from the battery housing 1 in a direction away from the core pack 2.

[0039] a secondary step 12, which is provided inside the primary step and is recessed relative to the primary step toward the core package 2;

[0040] A reinforcing rib bracket 7 is provided above the explosion-proof exhaust hole and connected to the secondary step 12. A first fracture groove 10 for fracture under stress is provided on the side of the reinforcing rib bracket 7 facing the core package 2.

[0041] An explosion-proof disc 8, which is laid on the explosion-proof exhaust hole and the secondary step 12;

[0042] The explosion-proof valve protection film 9 is laid on the first step.

[0043] In a preferred embodiment of the pressure relief structure of the battery housing, a second fracture groove for fracture under stress is provided on the side of the explosion-proof disc 8 facing the core package 2 .

[0044] In a preferred embodiment of the pressure relief structure of the battery casing, the second fracture groove surrounds the side of the secondary step 12 away from the primary step 11 .

[0045] In a preferred embodiment of the pressure relief structure of the battery casing, the second fracture groove is an annular groove.

[0046] In a preferred embodiment of the pressure relief structure of the battery housing, the upper surface of the reinforcing rib bracket 7 is flush with the upper surface of the secondary step 12 .

[0047] In a preferred embodiment of the pressure relief structure of the battery housing, the reinforcing rib bracket 7 is a cross-shaped, 'M'-shaped, 'H'-shaped, mesh-shaped, or stripe-shaped structure.

[0048] In a preferred embodiment of the pressure relief structure of the battery housing, the explosion-proof exhaust hole is an elliptical hole, and the first-level step 11 and the second-level step 12 are runway-type structures surrounding the elliptical hole.

[0049] In a preferred embodiment of the pressure relief structure of a battery housing, the battery housing 1 is a blade-shaped structure, an explosion-proof area is provided downward from the bottom of the battery housing 1, and the explosion-proof exhaust hole is located in the explosion-proof area.

[0050] In a preferred embodiment of the pressure relief structure of the battery housing, a positive electrode support is provided at one end of the battery housing 1 to cover the positive electrode top cover 3 of the positive electrode support, and a negative electrode support is provided at the other end of the battery housing 1 to cover the negative electrode top cover 4 of the negative electrode support.

[0051] In a preferred embodiment of the pressure relief structure of the battery housing, a core pack insulating sheet 5 is provided between the battery housing 1 and the core pack 2 .

[0052] In one embodiment, the battery housing 1 is a square battery housing 1 .

[0053] In one embodiment, the pressure relief structure of the battery housing comprises a square housing in the shape of a "blade," with the positive electrode top cover 3 and the negative electrode top cover 4 connected to the two sides of the housing, respectively. An explosion-proof area is provided downwardly from the bottom of the housing, which is equipped with explosion-proof vents, an explosion-proof valve boss 6, and a reinforcing rib support 7. The reinforcing rib support 7 is structurally arranged in the explosion-proof valve area of ​​the housing, flush with the secondary step; at the same time, an induced first fracture groove 10 is provided on the reinforcing rib support 7. When the pressure inside the battery exceeds a set threshold, the first fracture groove 10 on the reinforcing rib support 7 is forced to fracture, and the high-temperature and high-pressure gas inside the battery is directed out simultaneously with the explosion-proof disc 8. The explosion-proof disc 8 is located above the secondary step 12 and the reinforcing rib support 7, and is connected flush with the primary step 11. When the pressure inside the battery exceeds a set threshold, the second fracture groove on the explosion-proof disc 8 is forced to fracture, and the high-temperature and high-pressure gas inside the battery is directed out simultaneously with the reinforcing rib.

[0054] In one embodiment, the rib bracket 7 has a cross-shaped structure, but can also be in a crisscross pattern, a well-shaped pattern, a mesh pattern, or a striped pattern. The rib bracket 7 can be made of a conventional metal material or a high-strength material such as a polymer. Besides being directly connected to the housing by stamping or die-casting, the ribs can also be connected to the housing by welding, snap-fitting, or other methods.

[0055] Finally, it should be noted that the described embodiments are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without making any creative work are within the scope of protection of this application.

[0056] The above description is merely illustrative of certain exemplary embodiments of the present invention. It goes without saying that those skilled in the art will be able to modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the above drawings and description are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. A pressure relief structure for a battery housing, characterized in that: These include, A battery housing, which is used to encapsulate the core pack, and the battery housing has explosion-proof exhaust holes; An explosion-proof valve boss is provided on the battery housing and surrounds the explosion-proof exhaust hole. The explosion-proof valve boss includes: A step surrounds the explosion-proof vent and protrudes from the battery housing in a direction away from the core pack. a second step, which is provided inside the first step and is recessed relative to the first step toward the core package; A reinforcing rib bracket is provided above the explosion-proof exhaust hole and connected to the secondary step, and a first fracture groove for fracture under stress is provided on a side of the reinforcing rib bracket facing the core package; An explosion-proof plate, which is laid on the explosion-proof exhaust hole and the secondary step; The explosion-proof valve protective film is laid on the first step.

2. A pressure relief structure for a battery housing according to claim 1, characterized in that: A second fracture groove for fracture under stress is provided on a side of the explosion-proof plate facing the core package.

3. A pressure relief structure for a battery housing according to claim 2, characterized in that: The second fracture groove surrounds a side of the secondary step away from the primary step.

4. A pressure relief structure for a battery casing according to claim 2, characterized in that: The second fracture groove is an annular groove.

5. The pressure relief structure of a battery casing according to claim 1, characterized in that: The upper surface of the reinforcing rib bracket is flush with the upper surface of the secondary step.

6. The pressure relief structure of a battery casing according to claim 1, characterized in that: The reinforcing rib bracket is a cross-shaped, M-shaped, well-shaped, mesh-shaped or stripe-shaped structure.

7. The pressure relief structure of a battery casing according to claim 1, characterized in that: The explosion-proof exhaust hole is an elliptical hole, and the first-level step and the second-level step are runway-type structures surrounding the elliptical hole.

8. The pressure relief structure of a battery casing according to claim 1, characterized in that: The battery housing is a blade-shaped structure. An explosion-proof area is provided downward from the bottom of the battery housing, and the explosion-proof exhaust hole is located in the explosion-proof area.

9. The pressure relief structure of a battery casing according to claim 1, characterized in that: One end of the battery housing is provided with a positive electrode support to cover the positive electrode top cover of the positive electrode support, and the other end of the battery housing is provided with a negative electrode support to cover the negative electrode top cover of the negative electrode support.

10. The pressure relief structure of a battery casing according to claim 1, characterized in that: A core pack insulating sheet is provided between the battery shell and the core pack.

Images