Anti-explosion liquid injection structure and battery

Abstract

The utility model provides a kind of explosion-proof liquid injection structure, comprising: battery shell, the battery shell forms a cavity, for accommodating roll core and electrolyte;Liquid injection component is set on the battery shell, one end of the liquid injection component is fixed on the battery shell, the other end is inserted into the cavity, and is immersed by electrolyte liquid level;Drain valve is set on the liquid injection component, for when the pressure in the cavity exceeds its opening pressure, the electrolyte is discharged through the liquid injection component;Explosion-proof valve is set on the battery shell, the opening pressure of the explosion-proof valve is greater than the opening pressure of the drain valve.In the utility model, the liquid injection component is connected between the battery exterior and the cavity, when the electrolyte in the cavity decreases, new electrolyte can be injected into the cavity through the liquid injection component, in addition, during the thermal runaway process of the battery, the liquid injection component can discharge electrolyte in advance to avoid the electrolyte exacerbating the thermal runaway of the battery.

Description

Technical Field

[0001] This utility model relates to the field of battery module technology, and in particular to an explosion-proof liquid injection structure and battery. Background Technology

[0002] The electrolyte in a lithium-ion battery is the core carrier for ion transport. It is formulated from lithium salts, organic solvents, and additives in specific proportions, and its performance directly affects the battery's energy density, safety, and lifespan. During the charge-discharge cycle, insufficient electrolyte can prevent some active materials from being properly wetted, hindering the battery's capacity. Furthermore, during the charge-discharge process of a lithium-ion battery, continuous redox reactions occur, gradually depleting the electrolyte.

[0003] CN206194853U discloses a vacuum-assisted electrolyte injection valve-type square battery. This battery allows for the removal of internal gas and replenishment of electrolyte in a vacuum or inert gas atmosphere by replacing the vacuum-assisted electrolyte injection tube and internally threaded cap, thereby improving battery efficiency and cycle life. However, this electrolyte injection structure lacks explosion-proof functionality and cannot pre-emptively drain the electrolyte during thermal runaway to reduce the intensity of the thermal runaway.

[0004] Therefore, an explosion-proof electrolyte filling structure and battery are proposed to address the problem that existing electrolyte filling structures do not have explosion-proof functionality and cannot pre-drain the electrolyte from the battery during thermal runaway, thereby reducing the intensity of battery thermal runaway. Utility Model Content

[0005] In view of this, the present invention proposes an explosion-proof electrolyte injection structure and battery, wherein a drain valve is configured on the electrolyte injection component, which can drain the electrolyte inside the battery during the battery thermal runaway process, thereby reducing the intensity of battery thermal runaway.

[0006] This utility model proposes an explosion-proof liquid injection structure, including: A battery casing that forms a cavity for accommodating the winding core and electrolyte; An electrolyte injection component is disposed on the battery casing. One end of the electrolyte injection component is fixed to the battery casing, and the other end extends into the cavity and is submerged in the electrolyte. A drain valve is provided on the injection component and is used to discharge the electrolyte through the injection component when the pressure in the cavity exceeds its opening pressure. An explosion-proof valve is installed on the battery casing, and the opening pressure of the explosion-proof valve is greater than the opening pressure of the drain valve.

[0007] Based on the above technical solution, preferably, the battery casing is provided with a connection hole; The injection component includes: The electrolyte injection tube is installed on the battery casing. One end passes through the connection hole, extends into the cavity, and is submerged in the electrolyte. The other end is equipped with the drain valve. The inside of the electrolyte injection tube is hollow and forms an injection channel. A limiting member is provided on the injection tube and located at the opening of the connection hole, and the end face of the limiting member abuts against the battery casing.

[0008] Based on the above technical solution, preferably, the end of the injection tube that is submerged in the electrolyte is set at an angle.

[0009] Based on the above technical solution, preferably, the injection tube and the limiting component are integrally formed.

[0010] Based on the above technical solution, preferably, the liquid injection tube is detachably connected to the battery casing; The injection component further includes a separator, which is disposed inside the injection tube and along the axial extension direction of the injection tube, dividing the injection channel into an inlet channel and an outlet channel.

[0011] Based on the above technical solution, preferably, the drain valve is detachably connected to the injection component.

[0012] Based on the above technical solution, preferably, the pressure-bearing surface of the drain valve is provided with several crack marks.

[0013] Based on the above technical solution, preferably, the injection channel is filled with electrolyte.

[0014] On the other hand, the present invention also provides a battery, wherein the battery is configured with the aforementioned explosion-proof liquid injection structure, wherein at least one winding core is accommodated in the cavity, and the liquid injection component is located in the gap between the winding core and the battery casing.

[0015] Based on the above technical solution, preferably, the cavity contains at least two cores, and the injection component of the explosion-proof injection structure is located in the gap between two adjacent cores.

[0016] The explosion-proof liquid injection structure and battery provided by this utility model have the following advantages compared with the prior art: 1. The electrolyte injection component connects the outside of the battery to the cavity. When the electrolyte in the cavity decreases, new electrolyte can be injected into the cavity through the electrolyte injection component. In addition, during the thermal runaway of the battery, the electrolyte injection component can drain the electrolyte in advance to avoid the electrolyte exacerbating the thermal runaway of the battery. 2. One end of the injection tube passes through the connection hole and extends into the cavity, and is immersed in the electrolyte. When the gas pressure inside the cavity is too high, the electrolyte will be forced into the injection tube and discharged to the outside of the cavity through the drain valve, thus realizing the outward discharge of the electrolyte. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a perspective view of an explosion-proof liquid injection structure according to the present invention; Figure 2 This is a perspective view of an explosion-proof liquid injection structure separated from the battery casing according to this utility model; Figure 3 This is a half-sectional perspective view of a battery according to the present invention; Figure 4 This is a perspective view of a battery according to the present invention.

[0019] The attached reference numerals indicate: 1. Battery casing; 101. Cavity; 102. Connecting hole; 2. Liquid injection component; 21. Liquid injection tube; 22. Limiting component; 23. Separator; 3. Drain valve; 4. Explosion-proof valve; 100. Core. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of this utility model clearer, the technical solutions of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0021] In the description of the embodiments of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "connected" and "linked" 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. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of this utility model based on the specific circumstances.

[0022] In the description of the embodiments of this utility model, it should be noted that the terms "center", "longitudinal", "lateral", "up", "down", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of 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. Therefore, they should not be construed as limitations on the embodiments of this utility model.

[0023] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.

[0024] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this utility model, and should not be construed as limiting this utility model.

[0025] The following disclosure provides numerous different embodiments or examples for implementing various structures of the present invention. To simplify the disclosure, specific examples of components and arrangements are described below. These are merely examples and are not intended to limit the scope of the invention. Furthermore, reference numerals and / or letters may be repeated in different examples. Such repetition is for simplification and clarity and does not in itself indicate a relationship between the various embodiments and / or arrangements discussed. In addition, examples of various specific processes and materials are provided in this invention; however, those skilled in the art will recognize the applicability of other processes and / or the use of other materials.

[0026] The technical solution is explained below. In the existing solution, the electrolyte injection structure does not have explosion-proof functionality. During battery thermal runaway, it is impossible to pre-drain the electrolyte from the battery to reduce the intensity of the thermal runaway. Therefore, if... Figure 1 As shown, this utility model provides an explosion-proof liquid injection structure, including: Battery casing 1 forms a cavity 101 for accommodating core 100 and electrolyte; The electrolyte injection component 2 is installed on the battery casing 1. One end of the electrolyte injection component 2 is fixed to the battery casing 1, and the other end extends into the cavity 101 and is submerged in the electrolyte. The drain valve 3 is provided on the injection component (2) and is used to discharge electrolyte through the injection component 2 when the pressure in the cavity 101 exceeds its opening pressure. An explosion-proof valve 4 is installed on the battery casing 1. The opening pressure of the explosion-proof valve 4 is greater than the opening pressure of the drain valve 3.

[0027] The electrolyte injection component 2 connects the outside of the battery to the cavity 101. When the electrolyte level in the cavity 101 decreases, new electrolyte can be injected into the cavity 101 through the electrolyte injection component 2. Furthermore, during thermal runaway of the battery, the pressure inside the cavity 101 gradually increases. When the pressure inside the cavity 101 exceeds the opening pressure of the drain valve 3, the drain valve 3 opens, and the electrolyte in the cavity 101 is discharged to the outside of the cavity 101 through the electrolyte injection component 2. When the pressure inside the cavity 101 exceeds the opening pressure of the explosion-proof valve 4, the explosion-proof valve 4 releases pressure. Therefore, this application can achieve the goal of preemptively draining the electrolyte during battery thermal runaway by the electrolyte injection component 2, thereby preventing the electrolyte from exacerbating the battery's thermal runaway.

[0028] like Figure 2 As shown, in order to stably fix the liquid injection component 2 on the battery casing 1, the battery casing 1 is provided with a connection hole 102; The liquid injection component 2 includes: The liquid injection tube 21 is installed on the battery casing 1. One end passes through the connection hole 102, extends into the cavity 101, and is immersed in the electrolyte. The other end is provided with a drain valve 3. The liquid injection tube 21 is hollow inside and forms a liquid injection channel. The limiting member 22 is disposed on the liquid injection tube 21 and located at the opening of the connection hole 102. The end face of the limiting member 22 abuts against the battery casing 1.

[0029] One end of the injection tube 21 passes through the connection hole 102 and extends into the cavity 101, where it is submerged in the electrolyte. When the gas pressure inside the cavity 101 is too high, the electrolyte will be forced into the injection tube 21 and discharged to the outside of the cavity 101 through the drain valve 3, thus achieving the outward discharge of the electrolyte.

[0030] Specifically, the limiting member 22 is circular, and the limiting ring 22 is sleeved on the outside of the liquid injection tube 21 and connected to the outside of the battery casing 1 through the limiting ring 22. It is used to fix the liquid injection tube 21 on the battery casing 1 and keep the liquid injection channel stably submerged in electrolyte.

[0031] like Figure 3 As shown, in order to allow the electrolyte to be discharged quickly from the cavity 101, the end of the injection tube 21 that is immersed in the electrolyte is set at an angle.

[0032] The bottom of the injection tube 21 is designed with a slope, which can increase the liquid entry area, reduce the resistance of electrolyte entering the injection tube 21, and allow the electrolyte to be discharged more smoothly.

[0033] like Figure 2 As shown, the injection tube 21 and the limiting component 22 are integrally formed. The injection tube 21 and the limiting component 22 are integrally formed by die casting. The materials of the injection tube 21 and the limiting component 22 can be selected from high-temperature resistant aluminum materials.

[0034] like Figure 2 As shown, in order to facilitate the injection of new electrolyte into the cavity 101, the injection tube 21 is detachably connected to the battery casing 1; The injection component 2 also includes a separator 23, which is disposed inside the injection pipe 21 and is arranged along the axial extension direction of the injection pipe 21 to divide the injection channel into a complementary inlet channel and an exhaust channel.

[0035] The injection tube 21 is detachably connected to the battery casing 1. When adding new electrolyte to the cavity 101, the injection tube 21 is removed from the battery casing 1, and the injection tube 21 is lifted up a bit to separate the end of the injection tube 21 that was originally in contact with the electrolyte from the electrolyte. Then, the new electrolyte is injected into the inlet channel. The gas inside the cavity 101 can be discharged out of the cavity 101 through the exhaust channel, thereby avoiding the increase of gas pressure inside the cavity 101 during the electrolyte injection process, which would affect the electrolyte injection.

[0036] Specifically, connecting threads can be provided on the outer wall of the injection tube 21 and the inner wall of the connecting hole 102. The injection tube 21 is also connected to the battery casing 1 by a threaded connection. Furthermore, a sealing ring can be fitted on the outside of the injection tube 21. When the injection tube 21 is rotated to a predetermined position, the limiting member 22 and the battery casing 1 respectively abut against different sides of the sealing ring. The sealing ring further seals the injection tube 21 and the battery casing 1, improving the sealing performance of the connection between the two.

[0037] like Figure 2 As shown, in order to make the drain valve 3 replaceable after damage, the drain valve 3 is detachably connected to the injection component 2.

[0038] The drain valve 3 is threadedly connected to the injection pipe 21. Specifically, the outer wall of the drain valve 3 and the inner wall of the injection pipe 21 are provided with matching connecting threads. The drain valve 3 is detachably connected to the injection pipe 21 by tightening the threads. Therefore, when the drain valve 3 is ruptured by the pressure of the cavity 101, it can be disassembled and replaced by rotating the drain valve 3.

[0039] In addition, since the drain valve 3 is detachable, when liquid injection is required, the drain valve 3 can be loosened and removed, and the electrolyte can be introduced into the cavity 101 from the injection channel.

[0040] like Figure 2 As shown, in order to ensure that the drain valve 3 can be broken stably, several cracking marks are provided on the pressure-bearing surface of the drain valve 3. The marks are designed to effectively guide the gas release when the pressure in the cavity 101 is too high.

[0041] To increase battery life, the electrolyte injection channel is filled with electrolyte. As the battery is used, the electrolyte level inside the cavity 101 will gradually decrease. By filling the electrolyte injection channel with a portion of the electrolyte, the electrolyte in the injection channel can be replenished into the cavity 101 when the electrolyte level inside the cavity 101 decreases.

[0042] The working principle of this explosion-proof liquid injection structure is that the opening pressure of the drain valve 3 is less than that of the explosion-proof valve 4. During the battery thermal runaway process, the drain valve 3 set on the liquid injection component 2 will break in advance, thereby draining the electrolyte inside the battery outward in advance and avoiding the electrolyte from aggravating the battery thermal runaway.

[0043] On the other hand, the present invention also provides a battery, which is equipped with the aforementioned explosion-proof liquid injection structure. The cavity 101 contains at least one core 100, and the liquid injection channel of the liquid injection component 2 is located in the gap between the core 100 and the battery casing 1 or in the gap between two adjacent cores 100.

[0044] Specifically, when there is only one core 100, since the core 100 is arc-shaped, there is a gap between the core 100 and the battery casing 1. The liquid injection channel of the liquid injection component 2 is located in the gap between the core 100 and the battery casing 1, ensuring that the electrolyte can be discharged quickly. When there are multiple cores 100, the liquid injection channel is located in the gap between two adjacent cores 100, which also ensures that the electrolyte is discharged outward from the liquid injection pipe.

[0045] In this battery, an explosion-proof electrolyte filling structure allows for the replenishment of electrolyte into the cavity and the discharge of electrolyte in the event of battery thermal runaway, thus preventing the electrolyte from exacerbating the battery's thermal runaway.

[0046] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. An explosion-proof liquid injection structure, characterized in that, include: The battery casing (1) forms a cavity (101) for accommodating the winding core (100) and the electrolyte; The liquid injection component (2) is disposed on the battery casing (1). One end of the liquid injection component (2) is fixed on the battery casing (1), and the other end extends into the cavity (101) and is submerged in the electrolyte. A drain valve (3) is provided on the injection component (2) for discharging the electrolyte through the injection component (2) when the pressure in the cavity (101) exceeds its opening pressure. An explosion-proof valve (4) is installed on the battery casing (1), and the opening pressure of the explosion-proof valve (4) is greater than the opening pressure of the drain valve (3).

2. The explosion-proof liquid injection structure as described in claim 1, characterized in that, The battery casing (1) is provided with a connection hole (102); The injection component (2) includes: The liquid injection tube (21) is installed on the battery casing (1). One end passes through the connection hole (102), extends into the cavity (101), and is submerged in the electrolyte. The other end is provided with the drain valve (3). The liquid injection tube (21) is hollow inside and forms a liquid injection channel. A limiting member (22) is provided on the liquid injection tube (21) and located at the opening of the connecting hole (102). The end face of the limiting member (22) abuts against the battery casing (1).

3. The explosion-proof liquid injection structure as described in claim 2, characterized in that, The end of the injection tube (21) that is submerged in the electrolyte is set at an angle.

4. The explosion-proof liquid injection structure as described in claim 3, characterized in that, The injection tube (21) and the limiting member (22) are integrally formed.

5. The explosion-proof liquid injection structure as described in claim 2, characterized in that, The liquid injection tube (21) is detachably connected to the battery casing (1); The injection component (2) further includes a separator (23), which is disposed inside the injection pipe (21) and is arranged along the axial extension direction of the injection pipe (21) to divide the injection channel into an inlet channel and an outlet channel.

6. The explosion-proof liquid injection structure as described in claim 1, characterized in that, The drain valve (3) is detachably connected to the injection component (2).

7. The explosion-proof liquid injection structure as described in claim 1, characterized in that, The pressure-bearing surface of the drain valve (3) is provided with several crack marks.

8. The explosion-proof liquid injection structure as described in claim 2, characterized in that, The injection channel is filled with electrolyte.

9. A battery, characterized in that, The battery is equipped with an explosion-proof liquid injection structure as described in any one of claims 1-8, wherein the cavity (101) contains at least one core (100), and the liquid injection member (2) is located in the gap between the core (100) and the battery casing (1).

10. The battery as claimed in claim 9, characterized in that, The cavity (101) contains at least two cores (100), and the injection component (2) of the explosion-proof injection structure is located in the gap between two adjacent cores (100).

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