Lithium supplement battery top cover and square battery

Abstract

The invention belongs to the technical field of batteries, and particularly relates to a lithium supplement battery top cover and a square battery, the lithium supplement battery top cover comprises a top cover body and a stop frame used for limiting a battery cell, the top cover body is provided with a negative pole and a positive pole, the stop frame is arranged at the bottom of the top cover body, a cavity is arranged in the stop frame, the cavity is provided with an opening I, and the opening II is provided with a negative pole. The first opening is located in the side face or the bottom of the stop frame, a lower cover for sealing the first opening is arranged in the area, where the first opening is located, of the stop frame, a lithium material is arranged in the cavity, and the lithium material is electrically connected with the negative pole. Safe lithium supplement of the negative electrode can be realized, the process difficulty is lower, the safety is high, and the internal space of the battery cannot be additionally occupied or foreign matters cannot exist in the battery.

Description

Technical Field

[0001] The present invention belongs to the technical field of batteries, and in particular relates to a lithium-supplemented battery top cover and a square battery. Background Art

[0002] With technological advancements, the market demands increasingly higher cycle life for energy storage and power batteries. Conventional lithium-ion batteries form a solid electrolyte interface film (SELIF) on the negative electrode during the initial charge and discharge process. This film formation consumes some lithium ions, resulting in a decrease in the number of active lithium ions during charge and discharge, lowering battery capacity and shortening cycle life. To replenish the lithium ions consumed by the film formation, a small amount of additional lithium material can be added to either the positive or negative electrode of the battery to compensate for the loss of lithium ions.

[0003] Conventional lithium replenishment technologies are divided into positive electrode replenishment and negative electrode replenishment. Positive electrode replenishment primarily involves adding lithium nickelate or lithium ferrite to the positive electrode formula. This approach offers low manufacturing complexity and high safety, but the lithium replenishment effect is poor. Negative electrode replenishment, on the other hand, typically involves adding metallic lithium to the negative electrode. However, due to its high reactivity, metallic lithium placed there easily reacts with substances in the air, resulting in poor safety. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a lithium-supplemented battery top cover and a square battery with safe negative electrode lithium supplementation, which has lower process difficulty, high safety, and does not occupy additional internal space of the battery or cause foreign matter to be present in the battery.

[0005] The present invention provides a lithium-supplemented battery top cover, comprising a top cover body and a stop frame for limiting the position of the battery cell, wherein the top cover body is provided with a negative electrode post and a positive electrode post, the stop frame is provided at the bottom of the top cover body, a cavity is provided inside the stop frame, the cavity has an opening one, the opening one is located on the side or bottom of the stop frame, and a lower cover for closing the opening one is provided in the area where the stop frame is located at the opening one, a lithium material is provided in the cavity, and the lithium material is electrically connected to the negative electrode post.

[0006] Furthermore, the stop frame is made of insulating material, a conductive layer is provided on the inner wall of the cavity, and a conductive contact point is provided on the top of the stop frame, and the lithium material is electrically connected to the negative electrode column through the conductive layer and the conductive contact point.

[0007] Furthermore, the top cover body includes an insulating plate cover and an aluminum plate cover, the aluminum plate cover is arranged on the top of the insulating plate cover, the negative pole and the positive pole are arranged on the aluminum plate cover, the stop frame is arranged at the bottom of the insulating plate cover, and a connector is arranged inside the insulating plate cover, and the conductive contact point is electrically connected to the negative pole through the connector.

[0008] Furthermore, the cavity passes through the top and bottom of the stop frame, the area where the cavity passes through the bottom of the stop frame forms the first opening, and the area where the cavity passes through the top of the stop frame forms the second opening. An upper cover is provided on the top of the stop frame to close the second opening, and the conductive contact point is provided on the upper cover.

[0009] Furthermore, the lithium material is a lithium sheet or a lithium block.

[0010] Furthermore, the number of cavities on the stop frame is more than two.

[0011] Furthermore, there are two or more stop frames.

[0012] Furthermore, an explosion-proof opening is provided on the top cover body, and an explosion-proof valve is installed on the explosion-proof opening.

[0013] Furthermore, the sides of the negative electrode column and the positive electrode column are both provided with a rubber-encapsulated structure.

[0014] The present invention further provides a square battery, characterized in that it is provided with a lithium-supplemented battery top cover as described in any one of claims 1 to 9.

[0015] The present invention has the beneficial effect of pre-embedding the lithium material within a retaining frame below the top cover body, and in combination with the arrangement of the lower cover, forming a sealed chamber for the lithium material. Before battery assembly, the sealed chamber protects the lithium material, preventing it from contact with air and moisture, and preventing the safety hazard of oxidation, thereby enhancing safety. Because the lithium material of the present invention is pre-embedded within the retaining frame and electrically connected to the negative electrode post, the lithium material and the negative electrode have the same potential. During battery assembly, the lower cover is opened, and the electrolyte enters the cavity through the opening and contacts the lithium material. Under low potential, the lithium material gradually dissolves into the electrolyte, thereby replenishing the lithium.

[0016] Compared to conventional positive electrode lithium replenishment methods, the present invention utilizes safe negative electrode lithium replenishment, which significantly improves battery cycle life. Compared to directly adding lithium to the negative electrode for replenishment, the present invention offers a lower level of process complexity, improved safety, greater operability, and greater mass production feasibility. Furthermore, compared to other methods that pre-embed lithium materials within the battery, the present invention eliminates the need for additional lithium material packaging. After replenishment, the retaining frame retains its original function without occupying additional battery space or causing the presence of foreign matter. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a schematic diagram of the exploded structure of the lithium battery top cover of the present invention.

[0018] Figure 2 It is a structural schematic diagram of the stop frame of the present invention.

[0019] Figure 3This is a schematic structural diagram of the stop frame of the present invention with the upper cover removed and the lower cover opened.

[0020] Figure 4 It is a schematic diagram of the layered structure of the stop frame of the present invention.

[0021] In the figure: 1. Stop frame; 101. Cavity; 102. Lower cover; 103. Upper cover; 104. Conductive layer; 105. Conductive contact point; 2. Lithium material; 3. Insulation plate cover; 4. Aluminum plate cover; 5. Negative electrode; 6. Positive electrode; 7. Explosion-proof valve; 8. Protective patch; 9. Sealing ring; 10. Electrode rubber coating; 11. PPS rubber coating layer. DETAILED DESCRIPTION

[0022] like Figure 1-Figure 4 As shown, the present invention provides a lithium-supplemented battery top cover, including a top cover body and a stop frame 1 for limiting the battery cell. The top cover body is provided with a negative electrode post 5 and a positive electrode post 6, and the stop frame 1 is provided at the bottom of the top cover body. The side of the stop frame 1 facing the bottom of the top cover body is the top of the stop frame 1. A cavity 101 is provided inside the stop frame 1, and the cavity 101 has an opening 1, and the opening 1 is located on the side or bottom of the stop frame 1, and a lower cover 102 is provided on the stop frame 1, and the lower cover 102 is located in the area where the opening 1 is located, and is used to close the opening 1. The lower cover 102 is specifically detachable, that is, it can be removed from the stop frame 1, and it can be provided on the stop frame 1 by snap-fitting or gluing. A lithium material 2 is provided in the cavity 101, and the lithium material 2 is electrically connected to the negative electrode post 5.

[0023] Based on the above arrangement, the present invention forms a sealed cabin for the lithium material 2 by pre-embedding the lithium material 2 in the stop frame 1 below the top cover body, combined with the arrangement of the lower cover 102. Before the battery is assembled, the sealed cabin protects the lithium material 2, preventing the lithium material 2 from contacting with air and moisture, and preventing the safety hazards caused by oxidation, thereby improving safety. Since the lithium material 2 of the present invention is pre-embedded in the stop frame 1 and electrically connected to the negative electrode post 5, the lithium material 2 has the same potential as the negative electrode. When the battery is assembled, the lower cover 102 is opened, and the electrolyte enters the cavity 101 along the opening and contacts the lithium material 2. Under low potential, the lithium material 2 gradually dissolves into the electrolyte, thereby replenishing lithium. Compared with the conventional positive electrode lithium replenishment method, the present invention adopts a negative electrode safe lithium replenishment method, which is more helpful in improving the cycle life of the battery. Compared with the method of directly adding lithium to the negative electrode plate for lithium replenishment, the process difficulty of the present invention is smaller and safer, the operability is stronger, and the mass production feasibility is higher. Compared to other methods that pre-embed lithium material 2 within the battery, the present invention eliminates the need for additional packaging for the lithium material 2. After lithium replenishment, the retaining frame 1 retains its original function without occupying additional space within the battery or causing foreign matter to accumulate. The present invention can also be applied to sodium-ion battery systems by replacing the lithium material 2 with sodium.

[0024] The retaining frame 1 is made of an insulating material, such as plastic, which effectively isolates the air and provides mechanical support of appropriate strength. A conductive layer 104, such as a copper sheet, is provided on the inner wall of the cavity 101, and a conductive contact point 105, such as a copper sheet, is provided on the top of the retaining frame 1. The lithium material 2 is electrically connected to the negative electrode post 5 via the conductive layer 104 and the conductive contact point 105. Based on this configuration, the electrical connection path between the lithium material 2 and the negative electrode post 5 is optimized without affecting the normal function of the retaining frame 1.

[0025] The top cover body includes an insulating plate cover 3 and an aluminum plate cover 4. The aluminum plate cover 4 is arranged on the top of the insulating plate cover 3. The negative electrode column 5 and the positive electrode column 6 are arranged on the aluminum plate cover 4. The stop frame 1 is arranged at the bottom of the insulating plate cover 3, with the top of the stop frame 1 facing the bottom of the insulating plate cover 3. A connector is provided inside the insulating plate cover 3. The conductive contact point 105 is electrically connected to the negative electrode column 5 through the connector. The connector can be a metal connector or other connector capable of achieving electrical connection. Based on the above arrangement, an effective connection between the lithium material 2 and the negative electrode column 5 is achieved while ensuring the performance and structural requirements of the top cover body itself.

[0026] like Figure 3 As shown, the cavity 101 passes through the top and bottom of the stop frame 1. The area where the cavity 101 passes through the bottom of the stop frame 1 forms the first opening, and the area where the cavity 101 passes through the top of the stop frame 1 forms the second opening. A top cover 103 is provided on the top of the stop frame 1 to close the second opening, and the conductive contact points 105 are provided on the top cover 103. This arrangement facilitates the arrangement of the conductive layer 104 and the conductive contact points 105, as well as the connection between the conductive layer 104 and the conductive contact points 105.

[0027] In the present invention, the lithium material 2 can be a lithium sheet or a lithium block, and its specific shape and size can be designed according to the actual lithium replenishment requirements. Figure 4 As shown, after the lithium material 2 is set in the cavity 101, the stop frame 1 is located in the cavity 101 area and has a three-layer structure. The outer layer is the stop frame 1 body, that is, the plastic outer layer, the middle layer is the conductive layer 104, and the inner layer is the lithium material 2.

[0028] In a preferred configuration of the present invention, the number of cavities 101 on the stop frame 1 is two or more. Based on this configuration, while ensuring that there is sufficient space in the cavities 101 to arrange the lithium material 2, the partitions between adjacent cavities 101 can serve as reinforcement ribs of the stop frame 1 to ensure the overall structural strength of the stop frame 1.

[0029] The stop frame 1 has two or more, such as Figure 1 Two are shown, and the specific number can be determined according to the battery design requirements.

[0030] The top cover body is provided with explosion-proof vents, namely, the insulation plate cover 3 and the aluminum plate cover 4. These vents are equipped with explosion-proof valves 7. When an abnormality within the battery causes a pressure increase, high-pressure gas ruptures the notched area of ​​the explosion-proof valve 7, forming a directional exhaust channel, releasing internal pressure and providing directional pressure relief to prevent explosions. Furthermore, a protective patch 8 is provided on the surface of the explosion-proof valve 7 to isolate foreign matter and prevent sharp objects such as screws and metal shavings from accidentally puncturing the explosion-proof valve 7 during assembly and transportation, leading to premature failure.

[0031] The sides of the negative electrode column 5 and the positive electrode column 6 are both provided with a rubber coating structure to ensure corresponding sealing and insulation. Specifically, the sides of the negative electrode column 5 and the positive electrode column 6 are both provided with a column rubber coating 10 and a PPS rubber coating layer 11, and a sealing ring 9 is also provided below the negative electrode column 5 and the positive electrode column 6.

[0032] The present invention also provides a prismatic battery equipped with the lithium-supplemented battery cover described above. The lithium-supplemented battery cover protects the lithium material 2 before battery assembly, preventing contact with air and moisture, and potentially oxidation, thereby enhancing safety. During battery assembly, the lower cover 102 is opened, and electrolyte enters the cavity 101 through the opening, coming into contact with the lithium material 2. Under low potential, the lithium material 2 gradually dissolves into the electrolyte, thereby replenishing the lithium. Safe lithium replenishment at the negative electrode significantly improves the battery's cycle life. Compared to directly adding lithium to the negative electrode for replenishment, the present invention offers a less complex process, greater safety, improved operability, and greater scalability for mass production. Compared to other methods that pre-embed the lithium material 2 within the battery, the present invention eliminates the need for additional packaging for the lithium material 2. After replenishment, the retaining frame 1 as a whole performs its normal function, without occupying additional space within the battery or causing the presence of foreign matter.

[0033] Those skilled in the art should understand that the discussion of any of the above embodiments is merely illustrative and is not intended to imply that the scope of protection of the present application is limited to these examples. In line with the present application, the technical features in the above embodiments or different embodiments may be combined, the steps may be implemented in any order, and there are many other variations of different aspects of one or more embodiments of the present application as described above, which are not provided in detail for the sake of simplicity.

[0034] The one or more embodiments of this application are intended to encompass all such substitutions, modifications, and variations that fall within the broad scope of this application. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of one or more embodiments of this application should be included in the scope of protection of this application.

Claims

1. A lithium battery cover, characterized in that: The invention comprises a top cover body and a stop frame (1) for limiting the position of the battery cell, wherein the top cover body is provided with a negative electrode column (5) and a positive electrode column (6), the stop frame (1) is provided at the bottom of the top cover body, and a cavity (101) is provided inside the stop frame (1), the cavity (101) has an opening 1, the opening 1 is located on the side or bottom of the stop frame (1), and the stop frame (1) is provided with a lower cover (102) for closing the opening 1 in the area where the opening 1 is located, and a lithium material (2) is provided in the cavity (101), and the lithium material (2) is electrically connected to the negative electrode column (5).

2. The lithium-ion battery top cover according to claim 1, wherein: The stop frame (1) is made of insulating material, a conductive layer (104) is provided on the inner wall of the cavity (101), and a conductive contact point (105) is provided on the top of the stop frame (1), and the lithium material (2) is electrically connected to the negative electrode (5) through the conductive layer (104) and the conductive contact point (105).

3. The lithium-ion battery top cover according to claim 2, wherein: The top cover body comprises an insulating plate cover (3) and an aluminum plate cover (4), wherein the aluminum plate cover (4) is arranged on the top of the insulating plate cover (3), the negative pole (5) and the positive pole (6) are arranged on the aluminum plate cover (4), the stop frame (1) is arranged at the bottom of the insulating plate cover (3), a connector is arranged inside the insulating plate cover (3), and the conductive contact point (105) is electrically connected to the negative pole (5) through the connector.

4. The lithium-ion battery top cover according to claim 2 or 3, wherein: The cavity (101) passes through the top and bottom of the stop frame (1), the area where the cavity (101) passes through the bottom of the stop frame (1) forms the first opening, and the area where the cavity (101) passes through the top of the stop frame (1) forms the second opening. The top of the stop frame (1) is provided with an upper cover (103) for closing the second opening, and the conductive contact point (105) is provided on the upper cover (103).

5. The lithium-ion battery top cover according to any one of claims 1 to 3, wherein: The lithium material (2) is a lithium sheet or a lithium block.

6. The lithium-ion battery top cover according to any one of claims 1 to 3, wherein: The number of cavities (101) on the stop frame (1) is more than two.

7. The lithium-ion battery top cover according to any one of claims 1 to 3, wherein: The stop frame (1) has more than two.

8. The lithium-ion battery top cover according to any one of claims 1 to 3, wherein: An explosion-proof opening is provided on the top cover body, and an explosion-proof valve (7) is installed on the explosion-proof opening.

9. The lithium-ion battery top cover according to any one of claims 1 to 3, wherein: The sides of the negative electrode column (5) and the positive electrode column (6) are both provided with a rubber encapsulation structure.

10. A square battery, characterized in that: A lithium-supplemented battery top cover as described in any one of claims 1 to 9 is provided.

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