Batteries and battery modules

Abstract

To provide a battery and a battery module with a high safety factor.SOLUTION: A battery includes a housing 1, a cell 2, and a current collector disc 3. A housing cavity is provided in the housing 1 and a pressure relief valve is provided on the housing 1. The cell 2 is provided within the housing cavity. The current collector disc 3 includes a first side surface 31 and a second side surface 32 which are provided facing each other. The first side surface 31 is connected to an end surface of the cell 2, and the second side surface 32 is connected to a bottom part of the housing cavity. The first side surface 31 is provided with a first groove 311 spaced apart from the end surface of the cell 2. The second side surface 32 is provided with a second groove 321 at a position facing the pressure relief valve. A gap is formed between an edge of the current collector disc 3 and a wall of the housing cavity to form a connection passage 4. The first groove 311 and the second groove 321 communicate through the connection passage 4.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention claims priority to a Chinese patent invention with invention number 202222332225.X, filed with the China Patent Office on September 1, 2022, and all contents of the above invention are incorporated herein by reference.

[0002] The present invention is in the field of power storage devices, for example batteries and battery modules. [Background technology]

[0003] In cylindrical lithium-ion batteries, the current collecting disk plays the role of collecting current. Research has shown that the structural design of the current collecting disk has a very strong correlation with the safety of the cell, and the installation form of the current collecting disk is that the entire current collecting disk is firmly welded to the surface of the cell tab. When the cell experiences thermal runaway, the current collecting disk will be stuck in the pressure relief opening with the deformation of the cell, and the active material and gas inside the cell will not be released in a timely manner, which will cause the battery to experience thermal runaway, resulting in safety issues such as fire and explosion. Summary of the Invention

[0004] The present invention provides batteries and battery modules with good quality and high safety factor.

[0005] In a first aspect, an embodiment of the invention comprises: a housing having an internal receiving cavity and a pressure relief valve disposed thereon; a cell disposed within the receiving cavity; The battery includes a current collecting disk having a first side and a second side opposite each other, the first side being connected to an end face of the cell and the second side being connected to a bottom of the accommodating cavity, the first side being provided with a first groove spaced apart from the end face of the cell, and the second side being provided with a second groove located directly opposite the pressure relief valve, forming a connecting passage spaced apart between an edge of the current collecting disk and a wall of the accommodating cavity, and the first groove and the second groove communicating with each other via the connecting passage.

[0006] In one embodiment, the bottom of the first groove has a wetting hole extending through the current collecting disk.

[0007] In one preferred embodiment of the battery, the cross section of the infiltration hole has the same shape as the cross section of the first groove.

[0008] In one embodiment, the first grooves and the second grooves are each provided in multiple numbers, the multiple first grooves are arranged at intervals around the axis of the current collecting disk, and the second groove is directly opposite the spaced area between two adjacent first grooves.

[0009] In one embodiment, a third groove is provided in the central region of the first side, the bottom of which is spaced apart from the end face of the cell, and each of the multiple first grooves is connected to the third groove.

[0010] In one embodiment, the first groove has an annular sector shape, and / or The second groove has an annular sector shape.

[0011] In one embodiment, the first groove and the second groove are the same size.

[0012] In one embodiment, the end face of the cell at the end closest to the current collector disk is flat.

[0013] In one embodiment, the distance between the bottom of the first groove and the second side is L1, the distance between the bottom of the second groove and the first side is L2, and L1=L2.

[0014] In a second aspect, an embodiment of the present invention provides a battery module including a battery as described above.

[0015] The beneficial effects of the present invention are as follows: by setting the first groove, the connecting passage and the second groove so that they are in communication with each other, it can ensure that the pressure relief valve and the inside of the cell are in communication with each other, the pressure relief valve can timely sense the change in gas pressure in the receiving cavity and timely perform pressure relief, when the cell expands, the first groove can provide the cell with a space to release the expansion, the gas generated inside the cell can flow through the first groove and the connecting passage into the second groove, and finally be released by the pressure relief valve installed on the top of the housing, the setting of the second groove ensures that there is a distance between the current collecting disk and the pressure relief valve, which avoids the current collecting disk being deformed to block the pressure relief valve, which avoids the pressure inside the battery not being released in a timely manner, which leads to safety problems such as fire and explosion, and ensures the safe use of the battery. [Brief description of the drawings]

[0016] [Figure 1] FIG. 2 is an exploded schematic view of a cell and current collector disk according to one embodiment of the present invention. [Diagram 2] 1 is a cross-sectional schematic diagram of a battery according to one embodiment of the present invention. [Diagram 3] FIG. 2 is a schematic diagram of a current collecting disk according to one embodiment of the present invention. [Figure 4] FIG. 2 is a schematic diagram of another current collecting disk according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] In this specification, unless otherwise specified or limited, the terms "communication", "connection", and "fixed" should be understood in a broad sense, and may refer to, for example, a fixed connection, a detachable connection, being integrated, a mechanical connection, an electrical connection, direct communication, indirect communication via an intermediate medium, internal communication between two elements, or an interactive relationship between two elements. A person skilled in the art can understand the meaning of the above terms in this specification according to the situation.

[0018] As shown in Figures 1 to 3, the battery provided by the present invention comprises a housing 1, a cell 2, and a current collecting disk 3, a storage cavity is provided inside the housing 1, a pressure relief valve (not shown) is provided on the housing 1, the cell 2 is provided within the storage cavity, the current collecting disk 3 has a first side 31 and a second side 32 provided opposite each other, the first side 31 is connected to an end face of the cell 2, and the second side 32 is connected to a bottom of the storage cavity, the first side 31 is provided with a first groove 311 spaced apart from the end face of the cell 2, and the second side 32 is provided with a second groove 321 located directly opposite the pressure relief valve, a connecting passage 4 is formed between the edge of the current collecting disk 3 and the wall of the storage cavity at a distance, and the first groove 311 and the second groove 321 are in communication with each other via the connecting passage 4. By setting the first groove 311, the connecting passage 4 and the second groove 321 in communication with each other, it is possible to ensure that the pressure relief valve and the inside of the cell 2 are in communication with each other, so that the pressure relief valve can timely sense the change in the gas pressure in the receiving cavity and timely perform pressure relief. When the cell 2 expands, the first groove 311 can provide the cell 2 with a space to release the expansion. The gas generated inside the cell 2 can flow through the first groove 311 and the connecting passage 4 into the second groove 321, and finally be released by the pressure relief valve provided on the housing 1. The setting of the second groove 321 ensures that the current collecting disk 3 and the pressure relief valve are spaced apart, so as to avoid the current collecting disk 3 being deformed to block the pressure relief valve, and the pressure inside the battery cannot be timely released, which may lead to safety problems such as fire and explosion, and ensure the safe use of the battery.

[0019] As shown in FIG. 4, the bottom of the first groove 311 is provided with a wetting hole 33 penetrating the current collecting disk 3. If the wetting hole 33 is not provided, the electrolyte cannot flow into the cell 2 without passing through the connecting passage 4. In this solution, the wetting hole 33 is provided in the current collecting disk 3, and the electrolyte can flow into the cell 2 through the wetting hole 33 during the injection into the battery, which increases the flow rate of the electrolyte, accelerates the infiltration of the electrolyte into the active material, and shortens the injection time. Furthermore, since the wetting hole 33 is closer to the center of the cell 2 than the connecting passage 4, the provision of the wetting hole 33 can make it easier for the electrolyte to wet the inside of the cell 2.

[0020] A plurality of first grooves 311 and a plurality of second grooves 321 are provided, and the plurality of first grooves 311 are arranged at intervals around the axis of the current collecting disk 3, and the second groove 321 faces the space between two adjacent first grooves 311. By providing a plurality of first grooves 311 and second grooves 321, a plurality of uneven structures can be formed on the current collecting disk 3, which can increase the strength of the current collecting disk 3 and reduce deformation of the current collecting disk 3. By placing the second groove 321 facing the space between two adjacent first grooves 311, the overall thickness of the current collecting disk 3 can be reduced, which is advantageous in reducing the volume and weight of the battery and increasing the energy density of the battery. In one embodiment, the current collecting disk 3 is formed by punching.

[0021] 2 and 3, in one embodiment, a third groove 312 is provided in the middle region of the first side surface 31, the bottom of which is spaced apart from the end surface of the cell 2, and all the first grooves 311 are connected to the third groove 312. By providing the third groove 312, the third groove 312 can connect all the first grooves 311, and when the cell 2 expands, gas can flow out from any of the first grooves 311, which can prevent gas from accumulating in a certain first groove 311 and causing the local pressure chamber to become excessively large. The provision of the third groove 312 can facilitate exhaust and pressure relief of the cell 2, and in this embodiment, the third groove 312 has a circular shape.

[0022] The first groove 311 has an annular sector shape, and the second groove 321 also has an annular sector shape. By providing the first groove 311 and the second groove 321 in an annular sector shape, the shapes of the first groove 311 and the second groove 321 can be matched to the shape of the current collecting disk 3 itself, facilitating processing, and the edges of the first groove 311 and the second groove 321 coincide with the radial direction of the current collecting disk 3, contributing to strengthening the strength of the current collecting disk 3 itself.

[0023] In this embodiment, the cross section of the infiltration hole 33 has the same shape as the cross section of the first groove 311. By making the cross section of the infiltration hole 33 have the same shape as the cross section of the first recessed groove 311, the size of the infiltration hole 33 can be made as large as possible, thereby improving the injection efficiency. The infiltration hole 33 and the first groove 311 are both annular sectors. The annular sector is the shape remaining after subtracting a concentric smaller sector from a larger sector.

[0024] The first grooves 311 and the second grooves 321 are the same size. By making the first grooves 311 and the second grooves 321 the same size, the first grooves 311 and the second grooves 321 are uniformly distributed on the current collecting disk 3, making the uneven structure on the current collecting disk 3 uniform and increasing the strength of multiple locations on the current collecting disk 3.

[0025] 2, in this embodiment, the distance between the bottom of the first groove 311 and the second side surface 32 is L1, and the distance between the bottom of the second groove 321 and the first side surface 31 is L2, where L1=L2. By making the distance between the bottom of the first groove 311 and the second side surface 32 equal to the distance between the bottom of the second groove 321 and the first side surface 31, the thickness of multiple points on the current collecting disk 3 can be made as uniform as possible, and stress deformation of the current collecting disk 3 can be reduced.

[0026] The end face of the cell 2 close to the current collecting disk 3 is flat. In this embodiment, a gap is provided between the end face of the cell 2 and the first groove 311 of the current collecting disk 3, and the gap area between the two is connected to the pressure relief valve on the housing 1 by the connecting passage 4 and the second groove 321. By making the end face of the cell 2 close to the current collecting disk 3 flat, the area of ​​the gap area between the cell 2 and the current collecting disk 3 can be guaranteed. When the cell 2 expands, there is enough space in the first groove 311 to absorb the expansion of the cell 2, and the pressure relief valve smoothly relieves pressure until the gas pressure in the receiving cavity is equilibrated, thereby ensuring the safety performance of the battery.

[0027] This embodiment provides a battery module including a battery according to any of the above embodiments, during use, a pressure relief valve on the battery housing 1 can timely relieve the pressure caused by the expansion of the cells 2, making the battery less likely to have safety issues such as explosion, and therefore the battery module including this battery has a high safety factor and good quality.

[0028] In the description herein, terms of orientation or positional relationship such as "upper", "lower", "left", and "right" are based on the orientation or positional relationship shown in the drawings, and are intended only to facilitate explanation and operation, and do not indicate or imply that the devices or elements shown have a specific orientation, and must be constructed or operated in a specific orientation, and therefore cannot be understood as limitations on the present invention. In addition, the terms "first" and "second" are used only to distinguish in the description, and have no special meaning.

[0029] In the present description, reference to terms such as "one embodiment," "example," and the like means that the features, structures, materials, or characteristics described with reference to this example or example are included in at least one example or example of the present invention. In the present description, general references to the above terms do not necessarily refer to the same example or example.

[0030] It should be noted that this specification is described according to embodiments, but each embodiment does not include only one independent technical solution, and the description in the specification is for clarity only, and those skilled in the art should consider the specification as a whole, and the technical solutions in many of the embodiments can also be appropriately combined to form other embodiments that can be understood by those skilled in the art. [Explanation of symbols]

[0031] 1, housing; 2, cell; 3, current collecting disc; 31, first side; 311, first groove; 312, third groove; 32, second side; 321, second groove; 33, infiltration hole; 4, connecting passage.

Claims

1. A housing having an accommodating cavity therein; a cell disposed within the receiving cavity; a current collecting disk having opposed first and second sides; The housing is provided with a pressure relief valve; The first side surface is connected to an end surface of the cell, and the second side surface is connected to a bottom of the receiving cavity. The first side surface is provided with a first groove spaced apart from the end surface of the cell, and the second side surface is provided with a second groove, forming a connecting passage spaced apart between an edge of the current collecting disk and a wall of the receiving cavity, and the first groove and the second groove communicate with each other through the connecting passage. the pressure relief valve is located in the housing directly opposite the second groove; The battery wherein a bottom of the first groove has a wetting hole penetrating the current collecting disk.

2. 2. The battery of claim 1, wherein a cross section of the wetting hole is the same shape as a cross section of the first groove.

3. A housing having an accommodating cavity therein; a cell disposed within the receiving cavity; a current collecting disk having opposed first and second sides; The housing is provided with a pressure relief valve. The first side surface is connected to an end surface of the cell, and the second side surface is connected to a bottom of the receiving cavity. The first side surface is provided with a first groove spaced apart from the end surface of the cell, and the second side surface is provided with a second groove, forming a connecting passage spaced apart between an edge of the current collecting disk and a wall of the receiving cavity, and the first groove and the second groove communicate with each other through the connecting passage. the pressure relief valve is located in the housing directly opposite the second groove; The first groove and the second groove are each provided in a plurality of pieces, the plurality of first grooves are arranged at intervals around the axis of the current collecting disk, and the second groove faces a space between two adjacent first grooves, A battery having a third groove in a central region of the first side surface, the bottom of which is spaced apart from the end face of the cell, and each of the multiple first grooves is in communication with the third groove.

4. The battery of claim 3 which satisfies at least one of the following: The first groove has an annular sector shape. The second groove has an annular sector shape.

5. 4. The battery of claim 3, wherein the first groove and the second groove are the same size.

6. 3. The battery according to claim 1, wherein the end face of the cell at the end closest to the current collecting disk is flat.

7. 3. The battery according to claim 1, wherein a distance between a bottom of the first groove and the second side surface is L1, a distance between a bottom of the second groove and the first side surface is L2, and L1=L2.

8. A battery module comprising the battery according to claim 1 or 2.

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