Battery and battery pack

Abstract

A battery and a battery pack relate to the technical field of power batteries. The battery comprises a shell, a first anti-explosion valve and a second anti-explosion valve. And a battery cell is arranged in the shell. A first cavity and a second cavity are formed between the battery cell and the inner walls of the two opposite sides of the shell respectively. The first anti-explosion valve is arranged on the shell and connected with the first cavity. The second anti-explosion valve is arranged on the shell and connected with the second cavity. The battery pack comprises the battery. The batteries of the battery pack can quickly eject gas or electrolyte, flame ejection and explosion after thermal runaway are prevented, and the safety performance is high.

Description

Technical Field

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

[0002] As a new type of energy storage device, power batteries are currently being widely used in various fields, including automotive, aerospace, and high-speed rail. With the development of the power battery industry, people are placing higher demands on their energy density, cycle performance, and other indicators. During use, power batteries may experience thermal runaway within their cells for various reasons. When thermal runaway occurs, a large amount of gas is generated in a short period of time. If the gas inside the battery cannot be discharged in time, there is a risk of explosion.

[0003] The inventors have found that existing batteries are generally equipped with explosion-proof valves at the end to discharge gas or electrolyte. For example, the battery pack and vehicle with publication number CN217606967U include: a battery cell body, an explosion-proof valve and two poles. The battery cell body is the main part of the battery cell, and the explosion-proof valve is provided at one end of the battery cell body close to the top of the tray, and the explosion-proof valve is above the battery cell. The explosion-proof valve is generally located in the middle of the battery. When the battery heats up, the free electrolyte needs to move from the cavity of the shell to the explosion-proof valve, so that the electrolyte cannot be sprayed out quickly. The electrolyte will further participate in the reaction during the movement process before it is sprayed out, and the thermal runaway cannot be stopped in time. Utility Model Content

[0004] The purpose of the utility model is to provide a battery and a battery pack, which can quickly eject gas or electrolyte, prevent flame ejection and explosion after thermal runaway, and have high safety performance.

[0005] The embodiment of the present utility model is achieved as follows:

[0006] In a first aspect, the present invention provides a battery, comprising:

[0007] A housing, wherein a battery cell is disposed in the housing, and a first cavity and a second cavity are formed between the battery cell and inner walls on opposite sides of the housing;

[0008] a first explosion-proof valve, which is disposed on the housing and connected to the first cavity;

[0009] A second explosion-proof valve is provided on the housing and connected to the second cavity.

[0010] In an optional embodiment, the first explosion-proof valve includes a first main body and a first explosion-proof wire, the first explosion-proof wire is arranged on the outside of the first main body, and the first explosion-proof wire is raised relative to the shell; the second explosion-proof valve includes a second main body and a second explosion-proof wire, the second explosion-proof wire is arranged on the outside of the second main body, and the second explosion-proof wire is raised relative to the shell.

[0011] In an optional embodiment, the thickness of the first body portion and the second body portion is less than the thickness of the shell.

[0012] In an optional embodiment, the thicknesses of the first body portion and the second body portion are different.

[0013] In an optional embodiment, an inner wall opening of the first explosion-proof wire close to the first main body portion gradually decreases in a direction away from the shell; an inner wall opening of the second explosion-proof wire close to the second main body portion gradually decreases in a direction away from the shell.

[0014] In an optional embodiment, notches are provided at the centers of the first body portion and the second body portion.

[0015] In an optional embodiment, the first explosion-proof valve and the second explosion-proof valve are arranged at two ends of the same side of the housing.

[0016] In an optional embodiment, a liquid injection hole is further provided on the shell.

[0017] In an optional embodiment, the electrolyte in the shell is a sodium ion electrolyte.

[0018] In a second aspect, the present invention provides a battery pack comprising a battery as described in any one of the aforementioned embodiments.

[0019] The beneficial effects of the embodiments of the present utility model are:

[0020] The battery of the present invention includes a shell, a first explosion-proof valve and a second explosion-proof valve. A battery cell is arranged in the shell. A first cavity and a second cavity are formed between the battery cell and the inner walls on both sides opposite to each other in the shell. The first explosion-proof valve and the second explosion-proof valve are both arranged on the shell. The first explosion-proof valve is connected to the first cavity. The second explosion-proof valve is connected to the second cavity. Since most of the free electrolyte exists in the cavity position, the explosion-proof valve is arranged in the cavity position in the battery. When the battery heat is too high, the electrolyte vaporizes and causes the battery to expand, breaking through the explosion-proof valve, and the free electrolyte or gas can be ejected in time to prevent flame spray and explosion after thermal runaway, thereby having high safety performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following is a brief introduction to the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying any creative work.

[0022] Figure 1 A schematic structural diagram of a battery provided by an embodiment of the present utility model from a first perspective;

[0023] Figure 2 A schematic diagram of the internal structure of a battery provided in an embodiment of the present utility model;

[0024] Figure 3 A schematic diagram of the structure of a battery provided by an embodiment of the present utility model from a second perspective;

[0025] Figure 4 This is a schematic structural diagram of a first explosion-proof valve of a battery provided in an embodiment of the present utility model.

[0026] Icon: 100-battery; 10-shell; 11-first cavity; 12-second cavity; 13-battery cell; 14-positive electrode sheet; 15-negative electrode sheet; 16-liquid injection hole; 20-first explosion-proof valve; 21-first main body; 22-first explosion-proof wire; 23-notch; 30-second explosion-proof valve; 31-second main body; 32-second explosion-proof wire. DETAILED DESCRIPTION

[0027] To make the purpose, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings herein can be arranged and designed in various different configurations.

[0028] 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. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without creative effort are also within the scope of protection of the present invention.

[0029] 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.

[0030] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer" and the like, indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, or are the orientations or positional relationships in which the utility model product is typically placed when in use. These terms are intended solely to facilitate the description of this utility model and to simplify the description, and are not intended to indicate or imply that the device or component referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on this utility model. Furthermore, the terms "first," "second," and "third," etc., are used solely to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0031] Furthermore, terms such as "horizontal" and "vertical" do not necessarily mean that a component must be absolutely horizontal or overhanging, but rather that it can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure must be completely horizontal, but rather that it can be slightly tilted.

[0032] It should also be noted that, in the description of this utility model, unless otherwise expressly specified or limited, the terms "disposed," "installed," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; mechanical connections, electrical connections; direct connections, indirect connections through an intermediate medium, and internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in this utility model based on the specific circumstances.

[0033] Please refer to Figure 1-Figure 3 , this embodiment provides a battery 100 including a battery pack 100, which includes a shell 10, a first explosion-proof valve 20 and a second explosion-proof valve 30. A battery cell 13 is provided in the shell 10. A first cavity 11 and a second cavity 12 are formed between the battery cell 13 and the inner walls on opposite sides of the shell 10. It can be understood that the battery cell 13 in this embodiment is made by a winding process, and the two sides of the battery cell 13 are arc-shaped structures. The shell 10 in this embodiment is a rectangular shell 10. When the battery cell 13 is placed in the shell 10, the arc-shaped structures on both sides of the battery cell 13 abut against the inner walls of the shell 10 to form a first cavity 11 and a second cavity 12. The battery 100 also contains an electrolyte. The free electrolyte will be stored in the first cavity 11 and the second cavity 12.

[0034] Optionally, in this embodiment, the number of battery cells 13 is two, and the battery cells 13 are stacked sequentially within the housing 10. The arc-shaped structures at the ends of the battery cells 13 are sequentially arranged to form a first cavity 11 and a second cavity 12 spaced apart from each other with the inner wall of the housing 10. In other embodiments, the number of battery cells 13 can be one or more than two. The number of battery cells 13 can be specifically set as needed and is not limited in this invention.

[0035] In this embodiment, both the first explosion-proof valve 20 and the second explosion-proof valve 30 are disposed on the housing 10. The first explosion-proof valve 20 is connected to the first cavity 11. The second explosion-proof valve 30 is connected to the second cavity 12. It is understood that when the battery 100 experiences thermal runaway, the electrolyte within the battery 100 vaporizes due to the high heat, causing the battery 100 to expand and open the first explosion-proof valve 20 and the second explosion-proof valve 30. This allows the free electrolyte or gas within the first cavity 11 and the second cavity 12 to be ejected from the housing 10.

[0036] Specifically, in this embodiment, the first explosion-proof valve 20 and the second explosion-proof valve 30 are disposed at opposite ends of the same side of the housing 10. Furthermore, the housing 10 is also provided with a positive electrode sheet 14 and a negative electrode sheet 15. The positive electrode sheet 14 and the negative electrode sheet 15 are disposed on the first side of the housing 10. The first explosion-proof valve 20 and the second explosion-proof valve 30 are disposed on the second side of the housing 10, opposite the first side. Because the first cavity 11 and the second cavity 12 are located on opposite sides of the housing 10, the first explosion-proof valve 20 and the second explosion-proof valve 30 are respectively located at opposite ends of the second side of the housing 10.

[0037] Furthermore, in this embodiment, the housing 10 is provided with an injection hole 16. The injection hole 16 is used to inject electrolyte into the housing 10. In this embodiment, the electrolyte in the housing 10 is a sodium ion electrolyte. The battery 100 in this embodiment is a sodium ion battery 100. In other embodiments, the battery 100 may also be a lithium ion battery 100.

[0038] Please refer to Figure 3 and Figure 4. Furthermore, the first explosion-proof valve 20 includes a first main body 21 and a first explosion-proof line 22. The first explosion-proof line 22 is arranged on the outside of the first main body 21, and the first explosion-proof line 22 is raised relative to the shell 10. The second explosion-proof valve 30 includes a second main body 31 and a second explosion-proof line 32. The second explosion-proof line 32 is arranged on the outside of the second main body 31, and the second explosion-proof line 32 is raised relative to the shell 10. It can be understood that when the battery 100 is in thermal runaway, the electrolyte in the battery 100 vaporizes due to the high heat, causing the battery 100 to expand and break through the first main body 21 and the second main body 31. The first explosion-proof line 22 and the second explosion-proof line 32 are raised relative to the shell 10 to prevent the sprayed electrolyte from splashing. In addition, the thickening of the first explosion-proof line 22 and the second explosion-proof line 32 can prevent the shell 10 from being torn when the first main body 21 and the second main body 31 are damaged.

[0039] Specifically, in this embodiment, the thickness of the first body portion 21 and the second body portion 31 is less than the thickness of the housing 10. It is understood that when the battery 100 experiences thermal runaway, the electrolyte within the battery 100 vaporizes, causing the battery 100 to expand. The first and second explosion-proof valves 20 and 30 located in the first and second cavities 11 and 12 are more susceptible to gas pressure and deformation. Reducing the thickness of the first and second body portions 21 and 31 makes them more susceptible to damage. It should be noted that the thickness of the first and second body portions 21 and 31 should ensure that the first and second explosion-proof valves 20 and 30 can open properly when the battery 100 experiences thermal runaway. As long as the above-mentioned technical effects can be achieved, the present invention does not impose any restrictions on the specific thickness of the first and second body portions 21 and 31.

[0040] Furthermore, the thicknesses of the first body portion 21 and the second body portion 31 are different. It is understood that when the battery 100 experiences thermal runaway, the electrolyte within the battery 100 vaporizes due to the high heat, causing the battery 100 to expand, potentially breaching either the first body portion 21 or the second body portion 31. Because the first and second cavities 11, 12 within the housing 10 are not sealed, i.e., they are connected, the pressures in the first and second cavities 11, 12 are equal. For example, in this embodiment, when the thickness of the first body portion 21 is greater than that of the second body portion 31, as the pressures in the first and second cavities 11, 12 gradually increase, the second body portion 31 breaches first, and the second explosion-proof valve 30 opens first. At this point, if the thermal runaway of the battery 100 is controlled, the pressures in the first and second cavities 11, 12 will not continue to increase, the first body portion 21 will not breach, and the first explosion-proof valve 20 does not need to open. If the thermal runaway of the battery 100 is not controlled, the pressure in the first cavity 11 and the second cavity 12 continues to increase, the first body portion 21 is also ruptured, and the first explosion-proof valve 20 opens, further discharging the electrolyte, alleviating the thermal runaway of the battery 100 and preventing the battery 100 from exploding. Optionally, in other embodiments, when the thickness of the first body portion 21 is less than that of the second body portion 31, the first body portion 21 is ruptured first, and the first explosion-proof valve 20 opens first. In this case, if the thermal runaway of the battery 100 is controlled, the second body portion 31 will not be ruptured, and the second explosion-proof valve 30 does not need to open. If the thermal runaway of the battery 100 is not controlled, the second body portion 31 is also ruptured, and the second explosion-proof valve 30 opens, further discharging the electrolyte.

[0041] In order to prevent the sprayed electrolyte from splashing, the inner wall opening of the first explosion-proof wire 22 close to the first main body 21 gradually decreases in the direction away from the shell 10. The inner wall opening of the second explosion-proof wire 32 close to the second main body 31 gradually decreases in the direction away from the shell 10. It can be understood that the first explosion-proof wire 22 surrounds the first main body 21 to form an opening. The second explosion-proof wire 32 surrounds the second main body 31 to form an opening. When the battery 100 thermally runs away, the first main body 21 and the second main body 31 break open, and the sprayed electrolyte is blocked by the inner walls of the first explosion-proof wire 22 and the second explosion-proof wire 32 to prevent splashing. In this embodiment, the inner walls of the first explosion-proof wire 22 and the second explosion-proof wire 32 are tilted so that the opening gradually decreases in the direction away from the shell 10, so that more sprayed electrolyte contacts the inner walls of the first explosion-proof wire 22 and the second explosion-proof wire 32.

[0042] To make it easier to break open the first and second body portions 21, 31, a notch 23 is provided at the center of each of the first and second body portions 21, 31. Specifically, in this embodiment, the notch 23 is cross-shaped. In other embodiments, the notch 23 may be in other shapes, such as a broken line or an arc. This is not a limitation of the present invention.

[0043] The battery 100 of the battery pack 100 provided in this embodiment has the following beneficial effects:

[0044] The battery 100 of the present invention includes a shell 10, a first explosion-proof valve 20 and a second explosion-proof valve 30. A battery cell 13 is arranged in the shell 10. A first cavity 11 and a second cavity 12 are formed between the battery cell 13 and the inner walls on both sides opposite to the shell 10. The first explosion-proof valve 20 and the second explosion-proof valve 30 are both arranged on the shell 10. The first explosion-proof valve 20 is connected to the first cavity 11. The second explosion-proof valve 30 is connected to the second cavity 12. Since most of the free electrolyte exists in the cavity position, the explosion-proof valve is arranged in the cavity position in the battery 100. When the heat of the battery 100 is too high, the electrolyte vaporizes and causes the battery 100 to expand, breaking through the explosion-proof valve, and the free electrolyte or gas can be ejected in time to prevent flame spraying and explosion after thermal runaway, with high safety performance.

[0045] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Those skilled in the art will readily appreciate that the present invention is susceptible to various modifications and variations. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A battery, characterized in that: include: A housing, wherein a battery cell is disposed in the housing, and a first cavity and a second cavity are formed between the battery cell and inner walls on opposite sides of the housing; a first explosion-proof valve, which is disposed on the housing and connected to the first cavity; A second explosion-proof valve is provided on the housing and connected to the second cavity.

2. The battery according to claim 1, characterized in that The first explosion-proof valve includes a first main body and a first explosion-proof wire, the first explosion-proof wire is arranged outside the first main body, and the first explosion-proof wire is raised relative to the shell; the second explosion-proof valve includes a second main body and a second explosion-proof wire, the second explosion-proof wire is arranged outside the second main body, and the second explosion-proof wire is raised relative to the shell.

3. The battery according to claim 2, characterized in that The thickness of the first body portion and the second body portion is smaller than the thickness of the housing.

4. The battery according to claim 3, characterized in that The first body portion and the second body portion have different thicknesses.

5. The battery according to claim 2, characterized in that The inner wall opening of the first explosion-proof wire close to the first main body gradually decreases in the direction away from the shell; the inner wall opening of the second explosion-proof wire close to the second main body gradually decreases in the direction away from the shell.

6. The battery according to claim 2, characterized in that Notches are provided at the centers of the first body portion and the second body portion.

7. The battery according to claim 1, characterized in that The first explosion-proof valve and the second explosion-proof valve are arranged at two ends of the same side of the housing.

8. The battery according to claim 1, characterized in that The shell is also provided with a liquid injection hole.

9. The battery according to claim 1, characterized in that The electrolyte in the shell is a sodium ion electrolyte.

10. A battery pack, characterized in that: The invention comprises a battery according to any one of claims 1 to 9.

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