Battery cell and battery with same

Abstract

The utility model discloses a single battery and a battery with the single battery, the single battery comprises a shell, a first plate and a second plate, a containing cavity is formed in the shell, and the shell is provided with a second plate; the anti-explosion valve is arranged on the first plate and communicates with the containing cavity; the electrode assembly is arranged in the containing cavity, the electrode assembly comprises a plurality of pole pieces which are arranged in a stacked mode, notches are formed in the edges of the pole pieces, the notches of the multiple pole pieces are opposite in the stacking direction of the pole pieces and communicate with one another and jointly define an exhaust channel, and the exhaust channel faces the first plate and is opposite to the anti-explosion valve in the thickness direction of the first plate. According to the single battery disclosed by the utility model, normal exhaust of the single battery can be ensured when the battery is subjected to thermal runaway, so that the occurrence of aggravation of the thermal runaway can be reduced, meanwhile, the exhaust speed of gas inside the exhaust channel can be accelerated, the exhaust effect of the single battery is improved, and the safety of the single battery is improved.

Description

Technical Field

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

[0002] Relevant technologies point out that lithium-ion battery electrodes are divided into wound and laminated types. The electrode group of a wound battery has an arc all around, and a large gap is left at the edge after entering the shell. During thermal runaway, exhaust is relatively smooth, and the gas can be discharged from the rounded corners around the electrode group. However, the laminated battery has right angles all around, and there is less space inside the battery. During thermal runaway, there is less space left for gas, which can easily lead to aggravation of thermal runaway. Utility Model Content

[0003] The utility model aims to solve at least one of the technical problems existing in the prior art. To this end, the utility model proposes a battery cell, which can ensure the normal exhaust of the battery cell when the battery has thermal runaway, thereby reducing the occurrence of aggravated thermal runaway, and at the same time, can accelerate the exhaust speed of the gas inside the exhaust channel, improve the exhaust effect of the battery cell, and improve the safety of the battery cell.

[0004] The utility model also provides a battery having the battery monomer.

[0005] A battery cell according to the first aspect of the utility model comprises: a shell having a housing cavity formed therein, the shell having a first plate; an explosion-proof valve, the explosion-proof valve being arranged on the first plate and communicating with the housing cavity; an electrode assembly, the electrode assembly being arranged in the housing cavity, the electrode assembly comprising a plurality of stacked pole pieces, edges of the pole pieces being formed with notches, the notches of the plurality of pole pieces being opposite and connected in the stacking direction of the pole pieces and jointly defining an exhaust channel, the exhaust channel being arranged toward the first plate and opposite to the explosion-proof valve in the thickness direction of the first plate.

[0006] According to the battery cell of the utility model, by forming a notch at the edge of the pole piece, the internal exhaust space of the battery cell is increased without adding other components, and the exhaust space will not be squeezed and blocked due to thermal runaway. Therefore, when thermal runaway occurs in the battery, normal exhaust of the battery cell can be guaranteed, thereby reducing the occurrence of aggravated thermal runaway. At the same time, the exhaust channel and the explosion-proof valve are arranged relative to each other, which can speed up the exhaust speed of the gas inside the exhaust channel, thereby improving the exhaust effect of the battery cell and improving the safety of the battery cell.

[0007] According to some embodiments of the present invention, in the thickness direction of the first plate, the ratio of the depth of the notch to the height of the pole piece is 0.01-0.05.

[0008] According to some embodiments of the present invention, in the length direction of the first plate, two ends of the notch respectively exceed two ends of the explosion-proof valve.

[0009] According to some embodiments of the present invention, the pole piece has a first edge and a second edge perpendicular to each other, the first edge is arranged toward the first plate and extends along the length direction of the first plate, and the notch is formed by cutting the angle between the adjacent first edge and the second edge.

[0010] According to some embodiments of the present invention, the notches are formed at both ends of the first side, and there are two explosion-proof valves, which are respectively opposite to the notches at both ends of the first side.

[0011] According to some embodiments of the present invention, at the notch position, the first side and the second side are connected by a straight line and / or a curve.

[0012] According to some embodiments of the present invention, at the notch position, the first side is connected to the second side by a straight line, and the angle between the straight line and the first side is 3°-10°.

[0013] According to some embodiments of the present invention, the first plate is a bottom plate of the shell, and the battery cell further includes: a bottom support plate, and the bottom support plate is arranged between the electrode assembly and the first plate.

[0014] According to some embodiments of the present invention, the battery cell further includes poles, and the poles are arranged on both sides of the shell in the length direction of the first plate.

[0015] A battery according to a second aspect of the present invention comprises a battery cell according to the first aspect of the present invention.

[0016] According to the battery of the utility model, the battery monomer of the first aspect is provided, thereby improving the overall performance of the battery.

[0017] Additional aspects and advantages of the present invention will be given in part in the following description, and in part will become apparent from the following description, or will be learned through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 is a schematic diagram of a battery cell according to an embodiment of the utility model;

[0019] Figure 2 yes Figure 1 A schematic diagram of an electrode assembly shown in ;

[0020] Figure 3 It is a schematic diagram of the positive electrode;

[0021] Figure 4 It is a schematic diagram of the negative electrode.

[0022] Reference numerals:

[0023] 100. Battery cell;

[0024] 10. housing; 11. accommodating chamber;

[0025] 20. Explosion-proof valve;

[0026] 30. Electrode assembly; 31. Pole sheet; 31a. Positive electrode sheet; 31b. Negative electrode sheet; 32. Pole tab; 32a. Positive electrode tab; 32b. Negative electrode tab;

[0027] 40, pole; 40a, positive pole; 40b, negative pole. DETAILED DESCRIPTION

[0028] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0029] Reference below Figure 1-Figure 4 A battery cell 100 according to an embodiment of the first aspect of the present invention is described.

[0030] like Figure 1 As shown, a battery cell 100 according to an embodiment of the first aspect of the utility model comprises: a shell 10, an explosion-proof valve 20 and an electrode assembly 30, wherein a housing 11 is formed inside the shell 10, and the shell 10 has a first plate; the explosion-proof valve 20 is arranged on the first plate and communicated with the housing 11; the electrode assembly 30 is arranged in the housing 11, and the electrode assembly 30 comprises a plurality of pole pieces 31 arranged in a stacked manner, and notches are formed at the edges of the pole pieces 31, and the notches of the plurality of pole pieces 31 are opposite and connected in the stacking direction of the pole pieces 31 and jointly define an exhaust channel, and the exhaust channel is arranged toward the first plate and opposite to the explosion-proof valve 20 in the thickness direction of the first plate.

[0031] Specifically, the housing 10 is mainly used to isolate the inside of the battery cell 100 from the outside, effectively preventing the inside of the battery cell 100 from being connected to the outside, thereby improving the reliability of the battery cell 100. The explosion-proof valve 20 is mainly used to discharge the gas inside the battery cell 100 to the outside of the accommodating chamber 11, thereby reducing the probability of thermal runaway of the battery cell 100. The electrode assembly 30 is a component in the battery cell 100 where an electrochemical reaction occurs. The plurality of pole sheets 31 include a plurality of positive pole sheets 31a and a plurality of negative pole sheets 31b. The positive pole sheets 31a and the negative pole sheets 31b are stacked in sequence to form the electrode assembly 30. It can be understood that the electrode assembly 30 can be a laminated type. In addition, a diaphragm is usually provided between the positive pole sheet 31a and the negative pole sheet 31b.

[0032] The notch formed at the edge of the pole piece 31 creates a certain space between the electrode assembly 30 and the first plate, and this space is formed as an exhaust channel. In this way, the internal exhaust space can be increased without adding additional components. At the same time, when the battery cell 100 has thermal runaway, the exhaust channel in the present application will not be squeezed and blocked, thereby ensuring the exhaust space and reducing the possibility of aggravation of thermal runaway.

[0033] The exhaust channel is arranged toward the first plate and is opposite to the explosion-proof valve 20 in the thickness direction of the first plate. Therefore, when the battery cell 100 generates gas during the cycle, the gas will enter the exhaust channel and gather. When the gathered gas inside the exhaust channel reaches a certain pressure, the gas can be discharged directly through the explosion-proof valve 20, thereby reducing the pressure inside the battery cell 100 and reducing the probability of thermal runaway.

[0034] According to the battery cell 100 of the embodiment of the utility model, a notch is formed at the edge of the pole piece 31, so that the internal exhaust space of the battery cell 100 is increased without adding other components, and this exhaust space will not be squeezed and blocked due to thermal runaway. Therefore, when thermal runaway occurs in the battery, normal exhaust of the battery cell 100 can be guaranteed, thereby reducing the occurrence of aggravated thermal runaway. At the same time, the exhaust channel and the explosion-proof valve 20 are arranged relative to each other, which can speed up the exhaust speed of the gas inside the exhaust channel, thereby improving the exhaust effect of the battery cell 100 and improving the safety of the battery cell 100.

[0035] According to some embodiments of the present invention, Figure 2As shown, in the thickness direction of the first plate, the ratio of the depth of the notch to the height of the pole piece 31 is 0.01-0.05. For example, the ratio of the depth h of the notch to the height m of the pole piece 31 can be 0.01, 0.02, 0.03, 0.04 or 0.05. In this way, the notch on the pole piece 31 will not occupy too large a proportion and affect the energy density of the battery cell 100, and the depth of the notch will not be too small, which is conducive to ensuring the exhaust space and ensuring the smooth exhaust of the battery cell 100 when thermal runaway occurs.

[0036] In some specific embodiments of the present invention, Figure 2 As shown, in the thickness direction of the first plate, the depth of the notch is 1mm-5mm. For example, in the thickness direction of the first plate, the depth h of the notch can be 1mm, 2mm, 3mm, 4mm or 5mm. In this way, the exhaust space can be made not too small, ensuring the exhaust smoothness of the battery cell 100 when thermal runaway occurs, thereby reducing the severity of thermal runaway; at the same time, the exhaust space can be made not too large, effectively avoiding the reduction of the energy density of the battery cell 100 caused by the excessive space.

[0037] According to some embodiments of the present invention, Figure 1 As shown, in the length direction of the first plate, the two ends of the notch respectively exceed the two ends of the explosion-proof valve 20. In this way, when the gas pressure inside the accommodating chamber 11 reaches a certain value, the explosion-proof valve 20 can be fully opened, thereby increasing the exhaust volume and improving the exhaust effect.

[0038] According to some embodiments of the present invention, Figure 1 As shown, the electrode sheet 31 has a first side and a second side perpendicular to each other, the first side is arranged toward the first plate and extends along the length direction of the first plate, and the notch is formed by cutting corners between the adjacent first side and the second side. The cutting corner forming structure is simple and easy to manufacture, thereby reducing the difficulty of producing the electrode assembly 30 and improving the production rate of the battery cell 100.

[0039] According to some embodiments of the present invention, Figure 1 As shown, both ends of the first side are formed with notches, and there are two explosion-proof valves 20, which are respectively opposite to the notches at both ends of the first side. In this way, the exhaust space can be increased, the exhaust effect can be improved, and the probability of the battery cell 100 exploding when the battery cell 100 has thermal runaway can be further reduced.

[0040] According to some embodiments of the present invention, Figure 1As shown, at the notch position, the first side and the second side are connected by a straight line and / or a curve. Specifically, at the notch position, the first side and the second side can be connected by a straight line, can be connected by a curve, or can be extended by a combination of straight and curved lines. Among them, the straight line and the curved line have a simple structure and are easy to make, which can reduce the difficulty of producing the electrode assembly 30 and increase the production rate of the battery cell 100; at the same time, the curve can also play a drainage role, which can reduce the generation of eddy currents, and then increase the air flow speed, so that the gas entering the exhaust channel can be quickly discharged, thereby further improving the exhaust effect.

[0041] According to some embodiments of the present invention, Figure 1-Figure 2 As shown, at the notch position, the first side and the second side are connected by a straight line, and the angle between the straight line and the first side is 3°-10°. In this way, the size of the exhaust channel space can be limited, so that the exhaust space defined between the electrode assembly 30 and the first plate can meet the exhaust requirements without affecting the energy density of the battery cell 100.

[0042] For example, the angle a between the straight line and the first side may be 3°, 4°, 5°, 6°, 7°, 8°, 9° or 10°.

[0043] According to some embodiments of the present invention, the first plate is the bottom plate of the housing 10, and the battery cell 100 further includes: a bottom support plate, which is disposed between the electrode assembly 30 and the first plate. The bottom support plate is mainly used to carry the electrode assembly 30, isolate the electrode assembly 30 and the bottom plate of the housing 10, and prevent the electrode assembly 30 from contacting the bottom plate of the housing 10 and causing a short circuit.

[0044] According to some embodiments of the present invention, the battery cell 100 further includes poles 40, which are arranged on both sides of the housing 10 in the length direction of the first plate. The poles 40 are connected to the tabs 32 correspondingly, so that the explosion-proof valve 20 and the poles 40 and the tabs 32 are not on the same side of the battery cell 100, so that when the battery cell 100 has thermal runaway, the high-temperature and high-pressure substances can be prevented from affecting the poles 40 and the tabs 32, thereby preventing the battery cell 100 from having a high-voltage short circuit.

[0045] Furthermore, the pole 40 includes a positive pole 40a and a negative pole 40b, and the tab 32 includes a positive tab 32a and a negative tab 32b. The positive pole 40a is connected to the positive tab 32a, and the negative pole 40b is connected to the negative tab 32b.

[0046] The battery according to the embodiment of the second aspect of the utility model includes the battery cell 100 according to the embodiment of the first aspect of the utility model.

[0047] According to the battery of the embodiment of the utility model, the battery cell 100 of the embodiment of the first aspect is provided, thereby improving the overall performance of the battery.

[0048] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0049] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present utility model, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0050] In the present invention, unless otherwise clearly specified and limited, the terms "install", "connect", "connect", "fix" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or a communication; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0051] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0052] Although the embodiments of the present invention have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A battery cell, characterized in that: include: A housing, wherein a receiving cavity is formed inside the housing, and the housing has a first plate; An explosion-proof valve, which is disposed on the first plate and communicates with the accommodating chamber; An electrode assembly is arranged in the accommodating cavity, and the electrode assembly includes a plurality of electrode sheets arranged in a stacked manner, and a notch is formed at the edge of the electrode sheet. The notches of the plurality of electrode sheets are opposite and connected in the stacking direction of the electrode sheets and jointly define an exhaust channel. The exhaust channel is arranged toward the first plate and is opposite to the explosion-proof valve in the thickness direction of the first plate.

2. The battery cell according to claim 1, characterized in that: In the thickness direction of the first plate, the ratio of the depth of the notch to the height of the pole piece is 0.01-0.

05.

3. The battery cell according to claim 1, characterized in that: In the length direction of the first plate, two ends of the notch respectively exceed two ends of the explosion-proof valve.

4. The battery cell according to claim 1, characterized in that: The pole piece has a first side and a second side perpendicular to each other, the first side is arranged toward the first plate and extends along the length direction of the first plate, and the notch is formed by cutting an angle between the adjacent first side and the second side.

5. The battery cell according to claim 4, characterized in that: The notches are formed at both ends of the first side, and there are two explosion-proof valves, which are respectively opposite to the notches at both ends of the first side.

6. The battery cell according to claim 4, characterized in that: At the notch position, the first side and the second side are connected by a straight line and / or a curve.

7. The battery cell according to claim 6, characterized in that: At the notch position, the first side is connected to the second side by a straight line, and an angle between the straight line and the first side is 3°-10°.

8. The battery cell according to claim 1, characterized in that: The first plate is the bottom plate of the shell, and the battery cell further includes: a bottom support plate, and the bottom support plate is arranged between the electrode assembly and the first plate.

9. The battery cell according to claim 1, characterized in that: It also includes poles, which are arranged on both sides of the housing in the length direction of the first plate.

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

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