Power battery and vehicle

Abstract

The utility model discloses a power battery which comprises a shell and a naked battery cell, the shell comprises a bottom shell, the bottom of the naked battery cell is provided with a negative current collecting disc, the negative current collecting disc comprises a disc-shaped main body, the disc-shaped main body is provided with at least two sunken grooves sunken towards the bottom shell, the bottoms of the sunken grooves protrude out of the disc-shaped main body, and the bottoms of the sunken grooves are provided with backflow holes. The middle part of the disc-shaped main body is provided with a convex part which is convex towards the bottom shell; the bottom shell is provided with at least two limiting grooves corresponding to the at least two sunken grooves, the sunken grooves are arranged in the limiting grooves to limit the naked battery cell, the middle part of the bottom shell is provided with a welding groove which is sunken towards the outer side corresponding to the convex part, the bottom shell is also provided with a flow guide groove, and the flow guide groove is communicated with the limiting grooves and the welding groove. According to the utility model, the sunken groove is formed, and the limiting groove corresponding to the sunken groove is formed in the bottom shell, so that the naked battery cell is limited, in addition, electrolyte below the negative current collecting plate and in the welding groove can flow back along the diversion trench and the backflow hole, and the absorption of the naked battery cell to the electrolyte is promoted.

Description

Technical Field

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

[0002] With the increasingly serious crisis of non-renewable energy and the strong guidance of national policies, electric vehicles have become the main trend of the future development of the automobile industry. As an important component of electric vehicles, power batteries have the highest installed capacity in the field of electric vehicles due to their advantages such as small size, high energy density and green environmental protection. At present, lithium-ion / sodium-ion cylindrical batteries have gradually become the mainstream products in the new energy industry due to their high energy density, good capacity consistency, and support for high-rate charging and discharging. However, there are problems: 1. CID laser welding is performed on the top cover connecting piece and the middle position of the top cover of the cylindrical power battery. When the vehicle is loaded with long-term vibration or roller test, the bare battery cell drives the collector plate connecting piece and the top cover connecting piece to rotate. The large torque directly impacts the CID laser welding position, resulting in the occurrence of battery open circuit; 2. When the cylindrical power battery is loaded with long-term vibration or roller test, the rotation of the bare battery cell brings impact to the resistance welding position of the shell bottom, which will further increase the probability of battery open circuit or battery leakage; 3. When the electrolyte accumulates under the collector plate and the groove at the bottom of the shell, it is difficult to be absorbed by the bare battery cell, which will affect the battery life. Summary of the invention

[0003] The utility model aims to provide a power battery and a vehicle to solve the problem that the rotation of a bare battery cell impacts the welding point of the power battery and causes the battery to open circuit.

[0004] In order to achieve the above-mentioned purpose, the utility model provides a power battery, including a shell and a bare battery cell arranged in the shell, the shell including a bottom shell located at the bottom of the shell, a negative electrode collector disk is arranged at the bottom of the bare battery cell, the negative electrode collector disk includes a disc-shaped main body, the disc-shaped main body is provided with at least two recessed grooves recessed toward the bottom shell, the bottom of the recessed groove protrudes the disc-shaped main body, and the bottom of the recessed groove is provided with a reflux hole, and the middle part of the disc-shaped main body is provided with a raised portion protruding toward the bottom shell; the bottom shell is provided with at least two limiting grooves corresponding to at least two of the recessed grooves, the recessed grooves are arranged in the limiting grooves to limit the bare battery cell, the middle part of the bottom shell is provided with a welding groove recessed toward the outside corresponding to the raised portion, the raised portion is arranged in the welding groove and is welded to the welding groove, and the bottom shell is also provided with a guide groove, which connects the limiting groove and the welding groove.

[0005] Preferably, at least two of the recessed grooves are arranged at intervals along the circumference of the negative electrode current collecting disk, and at least two of the recessed grooves are arranged at the edge of the negative electrode current collecting disk.

[0006] Preferably, one end of the guide groove is communicated with the limiting groove, and the other end of the guide groove is communicated with the welding groove.

[0007] Preferably, there are three recessed grooves, which are evenly arranged on the edge of the negative electrode current collecting plate; there are three limiting grooves, which are arranged in one-to-one correspondence with the three recessed grooves; there are three guide grooves, which are arranged in one-to-one correspondence with the three limiting grooves, one end of each guide groove is connected to the corresponding limiting groove, and the other end of each guide groove is connected to the welding groove.

[0008] Preferably, the depth of the limiting groove is greater than or equal to 0.3 mm and less than or equal to 0.6 mm.

[0009] Preferably, the welding groove and the limiting groove are integrally stamped and formed on the bottom shell, and the recessed groove is integrally stamped and formed on the negative electrode current collecting plate.

[0010] Preferably, the disc-shaped body is further provided with at least two welding portions protruding toward the bare battery cell, and at least two of the welding portions are arranged in the area between the protruding portion and the concave groove.

[0011] Preferably, there are one or more reflux holes.

[0012] The utility model also provides a vehicle, comprising the power battery.

[0013] Compared with the prior art, the utility model sets a recessed groove on the disc-shaped main body and sets a limiting groove on the bottom shell corresponding to the recessed groove, so as to limit the bare battery cell by using the recessed groove and the limiting groove together. In addition, the electrolyte under the negative electrode collecting plate and in the welding groove can flow back along the guide groove and the reflux hole, so as to promote the bare battery cell to absorb the electrolyte. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is a structural diagram of the negative electrode current collector of an embodiment of the utility model at one angle.

[0015] Figure 2 This is a structural diagram of the negative electrode current collector from another angle of the embodiment of the utility model.

[0016] Figure 3 This is a structural diagram of an embodiment of the utility model in which a negative electrode current collector is arranged on the negative electrode of a bare battery cell.

[0017] Figure 4 It is a three-dimensional structural diagram of the shell of an embodiment of the utility model at one angle.

[0018] Figure 5 It is a top view of the structure of the shell of the embodiment of the utility model.

[0019] Figure 6 It is a three-dimensional structural diagram of the housing of an embodiment of the utility model from another angle.

[0020] Figure 7 This is a cross-sectional structural diagram of a power battery according to an embodiment of the utility model.

[0021] Figure 8 for Figure 7 Enlarged view of point A in the middle. DETAILED DESCRIPTION

[0022] In order to explain the technical content, structural features and effects achieved by the present invention in detail, the following is a detailed description in conjunction with the implementation modes and the accompanying drawings.

[0023] like Figures 1 to 8 As shown, the embodiment of the utility model provides a power battery, including a shell 1 and a bare cell 2 arranged in the shell 1, the shell 1 includes a bottom shell 11 located at the bottom of the shell 1, and a negative electrode current collecting plate 3 is arranged at the bottom of the bare cell 2, and the negative electrode current collecting plate 3 includes a disc-shaped body 31, and the disc-shaped body 31 is provided with at least two recessed grooves 32 recessed toward the bottom shell 11, the bottom of the recessed groove 32 protrudes from the disc-shaped body 31, and the bottom of the recessed groove 32 is provided with a reflux hole 321, and the middle of the disc-shaped body 31 is provided with A raised portion 33 is provided which protrudes toward the bottom shell 11; the bottom shell 11 is provided with at least two limiting grooves 12 corresponding to the at least two recessed grooves 32, the recessed grooves 32 are arranged in the limiting grooves 12 to limit the bare battery cell 2, and a welding groove 14 which is recessed toward the outside is provided in the middle part of the bottom shell 11 corresponding to the raised portion 33, the raised portion 33 is arranged in the welding groove 14 and is welded to the welding groove 14, and a guide groove 13 is also provided on the bottom shell 11, and the guide groove 13 connects the limiting groove 12 and the welding groove 14.

[0024] Specifically, the power battery is a cylindrical power battery, and the shell 1 and the bare cell 2 are both cylindrical structures. The shell 1 is a steel shell structure with an opening at the upper end. A bottom shell 11 is arranged at the bottom of the shell 1. One side of the negative electrode current collecting plate 3 is connected to the bare cell 2, and the other side of the negative electrode current collecting plate 3 is connected to the bottom shell 11. The material of the negative electrode current collecting plate 3 is one of copper, nickel, copper-nickel composite material, aluminum, etc. The reflux hole 321 is a through hole, and there are one or more reflux holes 321 to facilitate the electrolyte to flow from the reflux hole 321 to the bare cell 2. A limiting groove 12 is arranged on the bottom shell 11 corresponding to the recessed groove 32, and the size of the limiting groove 12 is slightly larger than the size of the recessed groove 32 to facilitate the recessed groove 32 to be embedded in the limiting groove 12 and to fit and bite for limiting. A welding groove 14 is provided on the bottom shell 11 to avoid the protrusion 33 and is welded to the protrusion 33. The welding groove 14 protrudes from the outer surface of the bottom shell 11. The top surface of the protrusion 33 and the bottom surface of the welding groove 14 are both circular, and the top surface of the protrusion 33 and the bottom surface of the welding groove 14 are butted against each other and welded together.

[0025] In the embodiment of the utility model, a recessed groove 32 is provided on the disc-shaped main body 31, and a limiting groove 12 is provided on the bottom shell 11 corresponding to the recessed groove 32, so that the recessed groove 32 cooperates with the limiting groove 12 to limit the bare battery cell 2. In addition, the electrolyte under the negative electrode collector plate 3 and in the welding groove 14 can reflux along the guide groove 13 and the reflux hole 321, so as to promote the bare battery cell 2 to absorb the electrolyte.

[0026] In the embodiment of the utility model, at least two recessed grooves 32 are arranged at intervals along the circumference of the negative electrode current collecting disk 3, and at least two recessed grooves 32 are arranged at the edge of the negative electrode current collecting disk 3. Specifically, as Figure 1 to Figure 2 As shown, the recessed groove 32 is arranged at the edge of the negative electrode current collecting disk 3 to improve the limiting effect on the bare battery cell 2 .

[0027] In the embodiment of the utility model, one end of the guide groove 13 is connected to the limiting groove 12, and the other end of the guide groove 13 is connected to the welding groove 14. Figures 4 to 6 As shown, the guide groove 13 is a straight groove structure. By connecting the guide groove 13 with the limiting groove 12 and the welding groove 14, the electrolyte in the limiting groove 12 can flow back to the bare battery cell 2 through the guide groove 13 and the reflux hole 321, thereby promoting the reflux absorption of the electrolyte.

[0028] In the embodiment of the utility model, Figures 1 to 6As shown, there are three recessed grooves 32, which are evenly arranged on the edge of the negative electrode current collecting plate 3; there are three limiting grooves 12, which are arranged one-to-one with the three recessed grooves 32; there are three guide grooves 13, which are arranged one-to-one with the three limiting grooves 12, and one end of each guide groove 13 is connected to the corresponding limiting groove 12, and the other end of each guide groove 13 is connected to the welding groove 14.

[0029] In the embodiment of the present utility model, the depth of the limiting groove 12 is greater than or equal to 0.3 mm and less than or equal to 0.6 mm. Figures 7 and 8 As shown, the depth H of the limiting groove 12 is greater than or equal to 0.3 mm and less than or equal to 0.6 mm.

[0030] In the embodiment of the utility model, the welding groove 14 and the limiting groove 12 are integrally stamped and formed on the bottom shell 11, and the recessed groove 32 is integrally stamped and formed on the negative electrode current collecting plate 3. Specifically, the integral stamping process is adopted, the process is simpler, and the molding effect is good. Of course, the molding method of the welding groove 14, the limiting groove 12 and the recessed groove 32 is not limited, as long as it can be molded.

[0031] In the embodiment of the utility model, the disc-shaped body 31 is further provided with at least two welding parts 34 protruding toward the bare battery cell 2, and the at least two welding parts 34 are provided in the area between the protruding part 33 and the concave groove 32. Specifically, as Figures 1 to 3 As shown, the disc-shaped body 31 is circular, and there are three welding parts 34 evenly distributed along the circumference of the disc-shaped body 31. Each welding part 34 is fan-shaped, and the welding parts 34 are welded to the full pole ears of the bare battery cell 2. A seepage hole 35 is provided between two adjacent welding parts 34.

[0032] The assembly method of the power battery of the utility model is as follows: first, the positive collector plate and the negative collector plate 3 are respectively fixed to the full pole ears at both ends of the bare battery cell 2 by laser welding; then the bare battery cell 2 is placed into the shell with the negative collector plate 3 facing the bottom shell 11; the bare battery cell 2 is gently rotated so that the recessed groove 32 on the negative collector plate 3 is adapted and snap-fitted with the limiting groove 12 of the bottom shell 11; then the raised portion 33 in the middle of the negative collector plate 3 is fixed to the welding groove 14 of the bottom shell 11 by resistance welding; finally, the positive collector plate connecting piece is fixed to the top cover by laser welding, the top cover connecting piece is bent, and the top cover is pressed down for assembly.

[0033] When the power battery of the embodiment of the utility model is subjected to vehicle vibration or roller test, when the bare battery cell 2 is about to drive the negative electrode current collecting plate 3 to produce a large rotational torque, the limiting groove 12 of the steel shell 1 offsets the stress and limits the negative electrode current collecting plate 3, and completely avoids the large torque of the bare battery cell 2 directly impacting the CID laser welding position or the resistance welding position in the middle of the bottom shell 11, and finally avoids the occurrence of open circuit of CID laser welding and resistance welding of the bottom shell 11, and at the same time promotes electrolyte reflux absorption, thereby ensuring the battery cycle life.

[0034] The embodiment of the utility model also provides a vehicle, including the above-mentioned power battery, which can effectively prevent the large torque of the bare battery cell 2 from directly impacting the CID laser welding position or the resistance welding position in the middle of the bottom shell 11, and finally avoid the occurrence of open circuit of CID laser welding and resistance welding of the bottom shell 11, while also promoting electrolyte reflux absorption, ensuring the battery cycle life and the quality of the vehicle.

[0035] The above disclosure is only a preferred example of the present invention, and certainly cannot be used to limit the scope of rights of the present invention. Therefore, equivalent changes made according to the scope of the patent application of the present invention still fall within the scope covered by the present invention.

Claims

1. A power battery, characterized in that: The invention comprises a shell and a bare cell arranged in the shell, wherein the shell comprises a bottom shell located at the bottom of the shell, a negative electrode current collecting disk is arranged at the bottom of the bare cell, the negative electrode current collecting disk comprises a disk-shaped body, the disk-shaped body is provided with at least two recessed grooves recessed toward the bottom shell, the bottom of the recessed groove protrudes from the disk-shaped body, and a reflux hole is arranged at the bottom of the recessed groove, and a protrusion protruding toward the bottom shell is arranged in the middle of the disk-shaped body; The bottom shell is provided with at least two limiting grooves corresponding to at least two of the recessed grooves, and the recessed grooves are arranged in the limiting grooves to limit the bare battery cell. The middle part of the bottom shell is provided with a welding groove recessed toward the outside corresponding to the raised portion, and the raised portion is arranged in the welding groove and welded to the welding groove. The bottom shell is also provided with a guide groove, which connects the limiting groove and the welding groove.

2. The power battery according to claim 1, characterized in that: At least two of the recessed grooves are arranged at intervals along the circumference of the negative electrode current collecting disk, and at least two of the recessed grooves are arranged at the edge of the negative electrode current collecting disk.

3. The power battery according to claim 2, characterized in that: One end of the guide groove is communicated with the limiting groove, and the other end of the guide groove is communicated with the welding groove.

4. The power battery according to claim 3, characterized in that: There are three recessed grooves, which are evenly arranged on the edge of the negative electrode current collecting plate; there are three limiting grooves, which are arranged in one-to-one correspondence with the three recessed grooves; there are three guide grooves, which are arranged in one-to-one correspondence with the three limiting grooves, one end of each guide groove is connected to the corresponding limiting groove, and the other end of each guide groove is connected to the welding groove.

5. The power battery according to claim 1, characterized in that: The depth of the limiting groove is greater than or equal to 0.3 mm and less than or equal to 0.6 mm.

6. The power battery according to claim 1, characterized in that: The welding groove and the limiting groove are integrally stamped and formed on the bottom shell, and the concave groove is integrally stamped and formed on the negative electrode current collecting disk.

7. The power battery according to claim 1, characterized in that: The disc-shaped body is also provided with at least two welding parts protruding toward the bare battery core, and at least two of the welding parts are arranged in the area between the protruding part and the concave groove.

8. The power battery according to claim 1, characterized in that: The number of the reflux holes is one or more.

9. A vehicle, characterized in that: A power battery comprising any one of claims 1 to 8.

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