Battery cell, battery pack, and electric device

Abstract

A battery cell, a battery pack, and an electric device. The battery cell comprises a shell (1). A boss (11) or a groove (12) is provided on the shell (1) on the side thereof opposite a terminal, and an explosion-proof through hole (13) is provided in the area of the boss (11) or the groove (12), an explosion-proof valve (14) is provided in the explosion-proof through hole (13), and a protective sheet (2) is provided on an inner bottom wall of the shell (1) at a top surface of the boss (11) or an opening of the groove (12). A ventilation channel (3) is provided on the circumferential outer side of the boss (11) or the circumferential inner side of the groove (12), and the ventilation channel (3) is in communication with the explosion-proof through hole (13) and the interior of the shell (1).

Description

Single cell, battery pack and electrical equipment

[0001] This application claims priority to the Chinese patent application filed with the China Patent Office on September 19, 2023, with application number 2023225554824. The entire contents of the above application are incorporated by reference into this application. Technical Field

[0002] The present application relates to the field of battery technology, and in particular to a single cell, a battery pack, and an electrical device. Background Art

[0003] In current lithium-ion batteries, the terminal and explosion-proof valve are typically located at the same end. When a single cell experiences a runaway condition, the emitted high-temperature gas or flame can easily burn the terminal and related connectors, causing high-voltage arcing or other secondary hazards. Therefore, in some related technologies, the explosion-proof valve is separated from the terminal. Specifically, the valve is located at the bottom of the aluminum shell, physically isolating the valve from the terminal. Technical issues

[0004] The connectivity between the interior of the separately installed single cell and the explosion-proof valve is poor, and even the core package structure inside the single cell is in direct contact with the explosion-proof valve, causing the explosion-proof hole to be blocked, so that the airflow inside the single cell cannot circulate normally with the outside world, resulting in poor explosion-proof effect. There is room for improvement. Technical Solutions

[0005] In a first aspect, the present application provides a single battery, comprising:

[0006] A housing, wherein the housing is provided with a boss or a groove on a side opposite to the pole, an explosion-proof through-hole is provided in the area of ​​the boss or the groove, an explosion-proof through-hole is provided in the explosion-proof through-hole, and a protective sheet is provided on the inner bottom wall of the housing at the top surface of the boss or the notch of the groove;

[0007] Wherein, a ventilation channel is provided on the circumferential outer side of the boss or the circumferential inner side of the groove, and the ventilation channel is connected with the explosion-proof through hole and the interior of the shell.

[0008] In a second aspect, the present application provides a battery pack, comprising the above-mentioned single cell battery, wherein the single cell battery is a square battery.

[0009] In a third aspect, the present application provides an electrical device including the above-mentioned battery pack. Beneficial effects

[0010] The single cell battery of the present application improves its own structure by setting up a ventilation channel to prevent the core package structure from blocking the pressure-releasing gas channel, causing the explosion-proof valve to be unable to explode and take effect, so as to solve the problem of blockage of the flow channel between the airflow inside the single cell battery and the explosion-proof valve, so that the explosion-proof valve can open when the internal pressure of the single cell battery reaches a preset value, thereby ensuring the safety of the battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] FIG1 is a schematic diagram of the three-dimensional structure of a single cell according to an embodiment of the present application;

[0012] FIG2 is a schematic diagram of the internal structure of a single cell according to an embodiment of the present application;

[0013] FIG3 is a schematic diagram of the internal structure of a single cell according to another embodiment of the present application;

[0014] FIG4 is a schematic diagram of the three-dimensional structure of an insulating member in a single cell according to an embodiment of the present application;

[0015] FIG5 is a schematic diagram of the internal structure of an insulating member in a single cell according to an embodiment of the present application;

[0016] FIG6 is a schematic diagram of the three-dimensional structure of an insulating member in a single cell according to another embodiment of the present application;

[0017] FIG7 is a schematic diagram of the internal structure of an insulating member in a single cell according to another embodiment of the present application;

[0018] FIG8 is a top view of a protective sheet in a single cell according to an embodiment of the present application;

[0019] FIG9 is a rear view of a protective sheet in a single cell according to an embodiment of the present application;

[0020] Figure: 1-shell, 11-boss, 12-groove, 13-explosion-proof through hole, 14-explosion-proof valve, 2-protective sheet, 21-adhesive, 22-fracture area, 3-ventilation channel, 4-insulating part, 41-ventilation through hole, 42-ventilation groove, 43-ventilation blind hole, 44-ventilation channel. Modes for Carrying Out the Invention

[0021] In the description of this application, it should be noted that the terms "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they cannot be understood as limiting this application.

[0022] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application pertains. The terms used herein in the specification of this application are for the purpose of describing specific embodiments only and are not intended to limit this application.

[0023] Referring to Figures 1-9, embodiments of the present application disclose a single cell, a battery pack, and an electrical device to address the problem of blockage in the flow channel between the airflow within the single cell and the explosion-proof valve 14. This allows the explosion-proof valve 14 to open when the internal pressure of the single cell reaches a preset value, thereby ensuring battery safety. This also ensures that the battery pack using this single cell has advantages such as high safety, smooth airflow, and good explosion-proof performance. The single cell can preferably be a prismatic secondary battery, i.e., a reusable, reversible, rechargeable battery, such as a storage battery.

[0024] Example 1 Structure of a Single Cell

[0025] Referring to Figures 1 to 3, the present single battery includes a housing 1. The housing 1 is provided with a boss 11 or a groove 12 on the side opposite to the pole. An explosion-proof through-hole 13 is provided in the area of ​​the boss 11 or the groove 12. An explosion-proof valve 14 is provided in the explosion-proof through-hole 13. A protective sheet 2 is provided on the inner bottom wall of the housing 1, located at the top surface of the boss 11 or the notch of the groove 12. A ventilation channel 3 is provided on the circumferential outer side of the boss 11 or the circumferential inner side of the groove 12, and the ventilation channel 3 connects the explosion-proof through-hole 13 and the interior of the housing 1.

[0026] In view of the problem that the flow channel between the internal airflow and the explosion-proof valve 14 of the existing single battery is blocked, the single battery of this embodiment improves its own structure, and a boss 11 or a groove 12 is provided on the inner bottom wall of the shell 1, and a ventilation channel 3 is provided on the circumferential outer side of the boss 11 or the circumferential inner side of the groove 12, so that the environment inside the shell 1 and the explosion-proof through-hole 13 are connected. Therefore, when the explosion-proof valve 14 is provided on the side of the single battery opposite to the pole, and the single battery is placed upright for use, the free electrolyte and the core pack structure inside the single battery will be accumulated on the inner bottom wall of the shell 1 or the inner bottom wall of the tight shell 1 under the action of gravity. By providing the ventilation channel 3, the core pack structure is prevented from blocking the pressure relief gas channel, resulting in the explosion-proof valve 14 being unable to explode and take effect, so as to solve the problem of blockage of the flow channel between the airflow inside the single battery and the explosion-proof valve 14, so that the explosion-proof valve 14 can be opened when the internal pressure of the single battery reaches a preset value, thereby ensuring the safety of the battery. At the same time, a protective sheet 2 is provided on the inner bottom wall of the housing 1 at the top surface of the boss 11 or the notch of the groove 12 to isolate the electrolyte and protect the explosion-proof valve 14 from corrosion by the electrolyte.

[0027] It should be noted that a boss 11 is provided on the inner bottom wall of the shell 1, and the boss 11 is protruding along a first direction, wherein the first direction is the direction of the single battery from the side where no pole is provided to the other side where the pole is provided; and a groove 12 is provided on the inner bottom wall of the shell 1, and the groove 12 is concave in the opposite direction of the first direction.

[0028] In some embodiments, the single cell further includes an insulating member 4, which is disposed between the inner bottom wall of the shell 1 and the core pack structure within the shell 1. This prevents overlap between the core pack structure and the shell 1, which could cause corrosion of the shell 1.

[0029] In some embodiments, referring to FIG. 2 , the present single cell battery includes a housing 1, with a boss 11 disposed on the inner bottom wall of the housing 1. An explosion-proof through-hole 13 is disposed on the side of the housing 1 opposite the terminal. The explosion-proof through-hole 13 is located within the area covered by the boss 11, and an explosion-proof valve 14 is disposed within the explosion-proof through-hole 13. A protective sheet 2 is disposed on the inner bottom wall of the housing 1, located on the top surface of the boss 11. A vent 3 is disposed circumferentially outside the boss 11, connecting the explosion-proof through-hole 13 with the interior of the housing 1. The dimensions of the boss 11 can range from a width of 0.5 mm to 5 mm and a height of 0.5 mm to 2 mm, effectively ensuring normal airflow within the single cell and external circulation, thereby enhancing explosion-proof effectiveness.

[0030] In some embodiments, the width of the boss 11 may be 0.5 mm, 1 mm, 1.5 mm, 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, 4.5 mm, 5 mm, etc. Of course, the width of the boss 11 may also be other values ​​between 0.5 mm and 5 mm.

[0031] In some embodiments, the height of the boss 11 may be 0.5 mm, 1 mm, 1.5 mm, 2 mm, etc. Of course, the height of the boss 11 may also be other values ​​between 0.5 mm and 2 mm.

[0032] In some embodiments, referring to Figure 3, the single battery includes a shell 1, the inner bottom wall of the shell 1 is provided with a groove 12, the shell 1 is provided with an explosion-proof through-hole 13 on the side opposite to the pole, the explosion-proof through-hole 13 is located in the area covered by the groove 12, an explosion-proof valve 14 is provided in the explosion-proof through-hole 13, and the inner bottom wall of the shell 1 is provided with a protective sheet 2 at the notch of the groove 12; wherein, a ventilation channel 3 is provided on the circumferential inner side of the groove 12, the ventilation channel 3 connects the explosion-proof through-hole 13 and the interior of the shell 1, wherein the size range of the groove 12 can be, the groove width of the groove 12 is 0.5mm-2mm, and the groove depth of the groove 12 is 0.2mm-1mm, which can effectively ensure that the airflow inside the single battery can circulate normally with the outside world, so as to improve the explosion-proof effect.

[0033] In some embodiments, the groove width of the groove 12 may be 0.5 mm, 1 mm, 1.5 mm, 2 mm, etc. Of course, the groove width of the groove 12 may also be other values ​​between 0.5 mm and 2 mm.

[0034] In some embodiments, the groove depth of the groove 12 may be 0.2 mm, 0.6 mm, 1 mm, 1.4 mm, 1.8 mm, 2 mm, etc. Of course, the groove depth of the groove 12 may also be other values ​​between 0.2 mm and 1 mm.

[0035] Referring to Figures 8 and 9 , in some embodiments, adhesive 21 is disposed between the protective sheet 2 and the inner bottom wall of the housing 1. Adhesive 21 itself forms a fractured region 22. Fractured region 22 breaks adhesive 21, creating a gap that creates a gas passage. This creates a gas passage between the protective sheet 2 and the inner bottom wall of the housing 1, effectively ensuring proper airflow within the battery cells and the outside world, enhancing explosion-proofing.

[0036] In some embodiments, the protective sheet 2 may be made of a waterproof and breathable material, such as PTFE, PETE, PES, PVDF, or PP. PTFE refers to polytetrafluoroethylene, PETE refers to polyester, PES refers to polyethersulfone, PVDF refers to polyvinylidene difluoride, and PP refers to polypropylene.

[0037] Example 2 Structure of a Single Cell

[0038] Based on Example 1, referring to Figures 4 and 5, in some embodiments, one or more ventilation holes 41 are provided on the insulating member 4 at a position opposite the explosion-proof valve 14, and one or more ventilation grooves 42 are provided at intervals on the side of the insulating member 4 facing the inner bottom wall of the shell 1. The ventilation grooves 42 extend along the width direction of the insulating member 4, and at least part of the ventilation grooves 42 are connected to at least part of the ventilation holes 41. The ventilation holes 41 extend along the height direction of the insulating member 4, and at the same time, the ventilation grooves 42 extend along the width direction of the insulating member 4, and the ventilation grooves 42 are also connected to the ventilation holes 41. This can increase the number of gas channels between the environment inside the shell 1 and the explosion-proof through hole 13, prevent the core package structure from blocking the pressure-releasing gas channel, and better improve the safety of the battery.

[0039] Example 3 Structure of a Single Cell

[0040] Based on Example 1, referring to Figures 6 and 7, in some embodiments, one or more blind vent holes 43 are provided on the side of the insulating member 4 facing the inner bottom wall of the housing 1 and opposite the explosion-proof valve 14. One or more ventilation channels 44 are provided between the two opposing walls of the insulating member 4, and at least some of the ventilation channels 44 are in communication with at least some of the blind vent holes 43. The blind vent holes 43 are non-through, meaning they do not penetrate the insulating member 4. At the same time, the ventilation channels 44 penetrate along the width of the insulating member 4 and are in communication with the blind vent holes 43. This increases the number of gas channels between the environment inside the housing 1 and the explosion-proof through hole 13, preventing the core pack structure from blocking the depressurized gas channel, thereby further improving battery safety.

[0041] Example 4: Structure of a Single Cell

[0042] Based on Example 1, in some embodiments, one or more ventilation holes 41 are provided on the insulating member 4 at a location opposite the explosion-proof valve 14, and one or more ventilation channels 44 are provided between opposing side walls of the insulating member 4, with at least some of the ventilation channels 44 communicating with at least some of the ventilation holes 41. The ventilation holes 41 extend through the height of the insulating member 4, while the ventilation channels 44 extend through the width of the insulating member 4 and are also in communication with the ventilation holes 41. This increases the number of gas passages between the environment inside the housing 1 and the explosion-proof through hole 13, preventing the core pack structure from blocking the pressure relief gas passages, thereby further improving battery safety.

[0043] Example 5 Structure of a Single Cell

[0044] Based on Example 1, in some embodiments, one or more blind ventilation holes 43 are provided on the side of the insulating member 4 facing the inner bottom wall of the housing 1 and opposite the explosion-proof valve 14. One or more ventilation grooves 42 are also provided at intervals on the side of the insulating member 4 facing the inner bottom wall of the housing 1. At least some of the ventilation grooves 42 are in communication with at least some of the ventilation blind holes 43. The ventilation blind holes 43 are non-through, that is, the ventilation blind holes 43 do not penetrate the insulating member 4. At the same time, the ventilation grooves 42 penetrate along the width direction of the insulating member 4 and are in communication with the ventilation blind holes 43. This can also increase the number of gas channels between the environment inside the housing 1 and the explosion-proof through hole 13, prevent the core pack structure from blocking the pressure relief gas channel, and better improve the safety of the battery.

[0045] Example 6 Structure of a Single Cell

[0046] Based on Example 2 or Example 4, in some implementations, the diameter of the ventilation hole 41 is 0.5 mm-3 mm, which can ensure that the air flow inside the single cell can circulate normally with the outside world and that the insulating member 4 has sufficient strength and insulation capacity.

[0047] In some embodiments, the aperture of the ventilation hole 41 may be 0.5 mm, 1 mm, 1.5 mm, 2 mm, 2.5 mm, 3 mm, etc. Of course, the aperture of the ventilation hole 41 may also be other values ​​between 0.5 mm and 3 mm.

[0048] Example 7 Structure of a Single Cell

[0049] Based on Example 2 or Example 5, in some embodiments, the width of the ventilation groove 42 is 0.5mm-1mm, and the depth of the ventilation groove 42 is less than or equal to 2 / 3 of the height of the insulating member 4, which can ensure that the airflow inside the single cell can circulate normally with the outside world, and can also ensure that the insulating member 4 has sufficient strength and insulation capacity.

[0050] In some embodiments, the width of the vent groove 42 may be 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1 mm, etc. Of course, the width of the vent groove 42 may also be other values ​​between 0.5 mm and 1 mm.

[0051] In some embodiments, the depth of the ventilation groove 42 may be 2 / 3, 1 / 2, 1 / 3, 1 / 6, etc. of the height of the insulating member 4. Of course, the depth of the ventilation groove 42 may also be other values ​​less than or equal to 2 / 3 of the height of the insulating member 4.

[0052] In some embodiments, the cross-section of the vent groove 42 may be in the shape of a triangle, a rectangle, an arc, a trapezoid, or the like.

[0053] In some embodiments, the groove depth of the ventilation groove 42 is 0.2 mm-1.5 mm. The groove depth of the ventilation groove 42 can be 0.2 mm, 0.6 mm, 1 mm, 1.5 mm, etc. Of course, the groove depth of the ventilation groove 42 can also be other values ​​between 0.2 mm and 1.5 mm.

[0054] Example 8 Structure of a Single Cell

[0055] Based on Example 3 or Example 5, in some embodiments, the diameter of the ventilation blind hole 43 is 0.5 mm to 5 mm, and the depth of the ventilation blind hole 43 is 1 / 4 to 3 / 4 of the height of the insulating member 4. This ensures that the airflow inside the single cell can flow normally with the outside world, while also ensuring that the insulating member 4 has sufficient strength and insulation capacity.

[0056] In some embodiments, the aperture of the air-permeable blind hole 43 may be 0.5 mm, 1 mm, 1.5 mm, 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, 4.5 mm, 5 mm, etc. Of course, the aperture of the air-permeable blind hole 43 may also be other values ​​between 0.5 mm and 5 mm.

[0057] In some embodiments, the hole depth of the ventilation blind hole 43 can be 1 / 4, 1 / 2, 3 / 4, etc. of the height of the insulating member 4. Of course, the hole depth of the ventilation blind hole 43 can also be other values ​​between 1 / 4-3 / 4 of the height of the insulating member 4.

[0058] Example 9: Structure of a Single Cell

[0059] Based on Example 3 or Example 4, in some embodiments, the height of the air passage 44 is less than or equal to 2 / 3 of the height of the insulating member 4, which can ensure that the airflow inside the single cell can circulate normally with the outside world and that the insulating member 4 has sufficient strength and insulation capacity.

[0060] In some embodiments, the height of the air channel 44 may be 2 / 3, 1 / 2, 1 / 3, 1 / 6, etc. of the height of the insulating member 4. Of course, the height of the air channel 44 may also be other values ​​less than or equal to 2 / 3 of the height of the insulating member 4.

[0061] In some embodiments, the cross-sectional shape of the air-permeable channel 44 may be triangular, rectangular, arc-shaped, trapezoidal, etc.

[0062] Example 10: Structure of a battery pack

[0063] The battery pack specifically includes a single cell in any one of the above-mentioned embodiments 1 to 9.

[0064] Example 11 Structure of an electrical device

[0065] The electrical equipment specifically includes a battery pack in the above-mentioned embodiment 10, wherein the electrical equipment may be a mobile device (such as a mobile phone, a laptop computer, etc.), an electric vehicle (such as a pure electric vehicle, a hybrid electric vehicle, a plug-in hybrid electric vehicle, an electric bicycle, an electric scooter, an electric golf cart, an electric truck, etc.), an electric train, a ship and a satellite, an energy storage system, etc., but is not limited thereto.

Claims

1. A single cell battery, comprising: A shell (1), wherein the shell (1) is provided with a boss (11) or a groove (12) on a side opposite to the pole, an explosion-proof through hole (13) is provided in the area of ​​the boss (11) or the groove (12), an explosion-proof through hole (13) is provided in the explosion-proof through hole (13), and a protective sheet (2) is provided on the inner bottom wall of the shell (1) at the top table of the boss (11) or the notch of the groove (12); A ventilation channel (3) is provided on the circumferential outer side of the boss (11) or the circumferential inner side of the groove (12), and the ventilation channel (3) communicates with the explosion-proof through hole (13) and the interior of the housing (1).

2. A single cell battery according to claim 1, further comprising an insulating member (4), wherein the insulating member (4) is arranged between the inner bottom wall of the shell (1) and the core package structure in the shell (1).

3. A single cell according to claim 2, wherein: One or more ventilation holes (41) are arranged on the insulating member (4) at a position opposite to the explosion-proof valve (14), and one or more ventilation grooves (42) are arranged at intervals on a side of the insulating member (4) facing the inner bottom wall of the shell (1), and at least part of the ventilation grooves (42) are connected to at least part of the ventilation holes (41).

4. A single cell according to claim 2, wherein: One or more air-permeable blind holes (43) are arranged on a side of the insulating member (4) facing the inner bottom wall of the shell (1) and opposite to the explosion-proof valve (14); one or more air-permeable channels (44) are arranged between two opposing side walls of the insulating member (4); at least part of the air-permeable channels (44) are in communication with at least part of the air-permeable blind holes (43).

5. A single cell according to claim 2, wherein: One or more ventilation holes (41) are arranged on the insulating member (4) at a position opposite to the explosion-proof valve (14), and one or more ventilation channels (44) are arranged between two opposing side walls of the insulating member (4), and at least part of the ventilation channels (44) are in communication with at least part of the ventilation holes (41).

6. A single cell according to claim 2, wherein: One or more ventilation blind holes (43) are arranged on the side of the insulating member (4) facing the inner bottom wall of the shell (1) and opposite to the explosion-proof valve (14); one or more ventilation grooves (42) are arranged at intervals on the side of the insulating member (4) facing the inner bottom wall of the shell (1); at least part of the ventilation grooves (42) are connected to at least part of the ventilation blind holes (43).

7. A single cell according to any one of claims 1 to 6, wherein: The width of the boss (11) is 0.5 mm to 5 mm, and the height of the boss (11) is 0.5 mm to 2 mm; Alternatively, the groove width of the groove (12) is 0.5 mm-2 mm, and the groove depth of the groove (12) is 0.2 mm-1.0 mm.

8. A single cell according to claim 3 or 5, wherein: The aperture of the ventilation hole (41) is 0.5 mm to 3 mm.

9. A single cell according to claim 3 or 6, wherein: The width of the ventilation groove (42) is 0.5 mm-1 mm, and the depth of the ventilation groove (42) is less than or equal to 2 / 3 of the height of the insulating member (4).

10. A single cell according to claim 3 or 6, wherein: The width of the ventilation groove (42) is 0.5 mm to 1 mm, and the depth of the ventilation groove (42) is 0.2 mm to 1.5 mm.

11. A single cell according to claim 4 or 6, wherein: The diameter of the air-permeable blind hole (43) is 0.5 mm to 5 mm, and the depth of the air-permeable blind hole (43) is 1 / 4 to 3 / 4 of the height of the insulating member (4).

12. A single cell according to claim 4 or 5, wherein: The height of the air permeable channel (44) is less than or equal to less than or equal to 2 / 3 of the height of the insulating member (4).

13. A single cell according to any one of claims 1 to 6, wherein: A backing glue (21) is provided between the protection sheet (2) and the inner bottom wall of the shell (1), and the backing glue (21) itself forms a fracture area (22).

14. A battery pack, comprising a single cell according to any one of claims 1 to 13, wherein the single cell is a square cell.

15. An electric device comprising the battery pack according to claim 14.

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