Bipolar column cover plate structure for steel shell battery and steel shell battery

Abstract

The utility model discloses a bipolar pole cover plate structure for a steel shell battery and the steel shell battery, the bipolar pole cover plate structure comprises a cover plate, the cover plate is provided with a first through hole and a second through hole, the first through hole is internally provided with a positive pole, and the second through hole is internally provided with a negative pole; each of the positive pole and the negative pole comprises a second lug boss arranged inside the cover plate, a vertical part corresponding to the vertical side surface of the cover plate, and a first lug boss arranged outside the cover plate; the positive pole and the negative pole are insulated from the cover plate through an insulating part, the insulating part is annular, one side of the insulating part wraps the first through hole and / or the second through hole, and the other side of the insulating part is inserted into the vertical part; according to the double-pole cover plate structure for the steel shell battery and the steel shell battery, the insulation structure is innovatively designed, the problem of insufficient insulation between the poles and the cover plate is solved, and the double-pole cover plate structure has the advantages of high safety, high reliability and easiness in manufacturing.

Description

A bipolar post cover structure for a steel-cased battery and the steel-cased battery Technical Field

[0001] This utility model relates to the field of lithium battery technology, and in particular to a bipolar post cover structure for steel-cased batteries and the steel-cased battery itself. Background Technology

[0002] Lithium batteries have advantages such as light weight, high voltage, long charge and discharge life, low self-discharge rate, and wide operating temperature range, and have been widely used in digital cameras, mobile phones, power tools and other fields.

[0003] Traditional steel-cased batteries, especially cylindrical batteries, typically employ a single-terminal design, with the positive or negative terminal directly connected to the cover plate. This results in the cover plate becoming charged, and an insulating film covering the cover plate provides external insulation. However, this insulation method still presents certain safety hazards. To address this, a bipolar battery has been designed. In this bipolar battery, the positive and negative terminals are not electrically connected to the cover plate; they are independent positive and negative terminals. However, in existing bipolar batteries, the insulation between the positive and negative terminals and the cover plate is insufficient, easily leading to short circuits or leakage. Therefore, a bipolar cover plate structure for steel-cased batteries is needed to solve the above problems. Summary of the Invention

[0004] The purpose of this utility model is to overcome the defect of insufficient insulation between the pole and the cover plate in the prior art, and to provide a bipolar pole cover plate structure for steel-cased batteries and a steel-cased battery. The insulation structure is innovatively designed, which solves the problem of insufficient insulation between the pole and the cover plate, and has the advantages of high safety, high reliability and easy manufacturing.

[0005] To achieve the above objectives, this utility model provides a bipolar terminal block cover structure for steel-cased batteries, comprising a cover plate with a first through hole and a second through hole. A positive terminal block is installed inside the first through hole, and a negative terminal block is installed inside the second through hole. The positive and negative terminal blocks include a second protrusion installed inside the cover plate, a vertical portion corresponding to the vertical side of the cover plate, and a first protrusion installed outside the cover plate. The positive and negative terminal blocks are insulated from the cover plate by an insulating portion, which is annular. One side of the insulating portion wraps around the first and / or second through holes, and the other side is inserted into the vertical portion.

[0006] Preferably, a negative electrode post is provided on one side of the positive electrode post; the positive electrode post and the negative electrode post are arranged side by side, with at least one end at the same height.

[0007] Preferably, the insulating part includes a first insulating part installed on the inner side and a second insulating part installed on the outer side; the second insulating part is annular and sleeved on the outer side of the first insulating part; the first insulating part insulates the side and bottom surfaces of the first through hole and / or the second through hole, and the second insulating part insulates the upper surface of the first through hole and / or the second through hole.

[0008] Preferably, the lower part of the first insulating portion is provided with a first insulating protrusion, and the inner side of the first insulating protrusion wraps around the outer side of the second protrusion.

[0009] Preferably, a reinforcing plate is installed between the bottom surface of the first protrusion and the insulating part. The inner side of the reinforcing plate contacts the outer side of the vertical part, and the bottom surface of the reinforcing plate contacts the upper part of the first insulating part and the upper part of the second insulating part, thus pressing the upper part of the first insulating part and the upper part of the second insulating part together.

[0010] Preferably, the upper part of the second insulating portion is provided with a second insulating protrusion, and the inner side of the second insulating protrusion wraps around the outer side of the reinforcing sheet.

[0011] Preferably, the insulating part adopts a multi-layer composite structure, including at least a ceramic layer and a polymer layer; the bonding method between the positive electrode post, the negative electrode post, the cover plate and the insulating part is a hot-press bonding method or an injection molding method.

[0012] Preferably, the upper surface of the second insulating part is provided with a plurality of first sealing ring protrusions, which are in contact with the bottom surface of the reinforcing sheet; the lower surface of the first insulating part is provided with a plurality of second sealing ring protrusions, which are in contact with the upper surface of the second protrusion; the inner surface of the first insulating part is provided with a plurality of third sealing ring protrusions, which are in contact with the side surface of the vertical part; and the outer surface of the first insulating part is provided with a plurality of fourth sealing ring protrusions, which are in contact with the side surface of the cover plate.

[0013] This utility model also provides a steel-cased battery, including the aforementioned bipolar post cover structure for a steel-cased battery; it also includes a steel-cased lower cover, the end of which is fitted with a cover plate, and a battery cell is installed in the internal cavity of the lower cover. One end of the battery cell is fitted with a positive electrode tab and a negative electrode tab. The positive electrode tab is connected to the positive terminal by welding; the negative electrode tab is connected to the negative terminal by welding; a steel-cased cover plate is welded to the upper part of the lower cover, and the steel-cased cover plate seals the battery cell and the lower cover.

[0014] Preferably, the side of the lower cover of the steel shell is provided with a liquid injection hole and a sealing plate for sealing the liquid injection hole. The upper surface of the steel shell cover is provided with an arc-shaped pressure relief valve. The positive and negative electrode tabs are coated with electrode insulating adhesive. The battery cell is covered with a diaphragm or insulating adhesive. The inner wall of the lower cover of the steel shell is coated with an insulating coating.

[0015] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0016] The positive and negative terminals of this invention are insulated from the cover plate by an insulating part. The insulating part is annular, with one side wrapping around the first through hole and / or the second through hole, and the other side inserted into the vertical part. Using the insulating part to wrap and insulate the cover plate can effectively solve the problem of insufficient insulation between the terminals and the cover plate, and has the advantages of high safety, high reliability and ease of manufacture. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 is a cross-sectional view of the cover plate provided by this utility model;

[0019] Figure 2 is a cross-sectional view of a bipolar column cover plate structure for a steel-cased battery provided by this utility model;

[0020] Figure 3 is a top view of a bipolar column cover plate structure for steel-cased batteries provided by this utility model;

[0021] Figure 4 is a cross-sectional view of the positive electrode post provided by this utility model;

[0022] Figure 5 is a cross-sectional view of the first insulating part provided by this utility model;

[0023] Figure 6 is a cross-sectional view of the second insulating part provided by this utility model;

[0024] Figure 7 is an exploded view of a steel-cased battery provided by this utility model;

[0025] Figure 8 is a schematic diagram of the installation of a steel-cased battery provided by this utility model;

[0026] Figure 9 is a schematic diagram of a finished steel-cased battery provided by this utility model.

[0027] The diagram includes:

[0028] 1. Cover plate; 11. First through hole; 12. Second through hole; 2. Positive electrode post; 3. Negative electrode post; 23. Second protrusion; 22. Vertical part; 21. First protrusion; 4. Insulating part; 41. First insulating part; 42. Second insulating part; 411. First insulating protrusion; 5. Reinforcing piece; 421. Second insulating protrusion; 422. First sealing ring protrusion; 412. Second sealing ring protrusion; 71. Steel shell lower cover; 8. Battery cell; 81. Positive electrode tab; 82. Negative electrode tab; 72. Steel shell cover plate; 73. Sealing plate; 74. Pressure relief valve; 83. Electrode tab insulating adhesive; 84. Insulating adhesive. Detailed Implementation

[0029] The technical solution of this embodiment of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiment is one embodiment of the present invention, and not all embodiments thereof. Based on this embodiment of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0030] Example 1

[0031] Please refer to Figures 1 to 6. This utility model provides a bipolar post cover structure for steel-cased batteries.

[0032] As shown in Figure 1, the bipolar post cover plate structure includes a cover plate 1. The cover plate 1 can be a rectangular plane, or a combination of a plane and an arc surface. The cover plate 1 can also be a circular plane. The cover plate 1 is provided with a first through hole 11 and a second through hole 12. The positive electrode post 2 is installed inside the first through hole 11, and the negative electrode post 3 is installed inside the second through hole 12.

[0033] As shown in Figures 2 and 3, the positive electrode post 2 and the negative electrode post 3 have the same structure, only their polarities are different. The cross-sections of the positive electrode post 2 and the negative electrode post 3 are both I-shaped, including a second protrusion 23 installed inside the cover plate 1, a vertical part 22 corresponding to the vertical side of the cover plate 1, and a first protrusion 21 installed outside the cover plate 1. The positive electrode post 2 and the negative electrode post 3 are insulated from the cover plate 1 by an insulating part 4. The insulating part 4 is annular with a U-shaped cross-section. One side of the insulating part 4 wraps around the first through hole 11 and / or the second through hole 12, and the other side is inserted into the vertical part 22. The insulating part 4 is used to wrap the cover plate 1 for insulation, ensuring that the electrode post is completely insulated from the cover plate 1, solving the problem of insufficient insulation between the electrode post and the cover plate 1, and has the advantages of high safety, high reliability and ease of manufacture.

[0034] As shown in Figures 2 and 3, a negative electrode post 3 is provided on one side of the positive electrode post 2; the positive electrode post 2 and the negative electrode post 3 are arranged side by side, with at least one end at the same height. In this embodiment, there is no height difference on the upper surface of the positive electrode post 2 and the negative electrode post 3, which facilitates the design and assembly of the battery pack; there is also no height difference on the lower surface, which facilitates welding with the battery cell 8.

[0035] In this embodiment, the insulating part 4 consists of two parts: a first insulating part 41 installed on the inner side and a second insulating part 42 installed on the outer side. The second insulating part 42 is annular and sleeved on the outside of the first insulating part 41. The cross-section of the first insulating part 41 is symmetrically L-shaped. Specifically, the first insulating part 41 insulates the side and bottom surfaces of the first through hole 11 and / or the second through hole 12, and the second insulating part 42 insulates the upper surface of the first through hole 11 and / or the second through hole 12. Thus, in this embodiment, the first insulating part 41 and the second insulating part 42 completely insulate the contact portion between the first through hole 11 or the second through hole 12 and the electrode post. The upper surface, side surface, and bottom surface of the first through hole 11 or the second through hole 12 are all wrapped to achieve enclosed insulation, thereby ensuring that the electrode post cannot contact or conduct with the cover plate 1.

[0036] As shown in Figure 2, the lower part of the first insulating part 41 is provided with a first insulating protrusion 411, and the inner side of the first insulating protrusion 411 wraps the outer side of the second protrusion 23. The first insulating protrusion 411 can block the lower part of the second protrusion 23 from getting close to the inside of the cover plate 1, which can prevent the second protrusion 23 from being electrically connected to the cover plate 1, and can also prevent other cables from electrically connecting the second protrusion 23 to the cover plate 1, thereby reducing the occurrence of lithium battery short circuits and improving the safety of lithium batteries.

[0037] In this embodiment, to facilitate subsequent welding, the bottom surface of the first insulating protrusion 411 is higher than the bottom surface of the second protrusion 23, thereby protruding the second protrusion 23 and facilitating subsequent welding with the electrode tab; in other embodiments, the bottom surface of the first insulating protrusion 411 and the bottom surface of the second protrusion 23 may be at the same height.

[0038] As shown in Figure 2, a reinforcing plate 5 is installed between the bottom surface of the first protrusion 21 and the insulating part 4. The inner side of the reinforcing plate 5 is in contact with the outer side of the vertical part 22, and the bottom surface of the reinforcing plate 5 is in contact with the upper part of the first insulating part 41 and the upper part of the second insulating part 42, pressing the upper part of the first insulating part 41 and the upper part of the second insulating part 42 together.

[0039] Furthermore, the reinforcing piece 5 is made of the same material as the terminal post, so the reinforcing piece 5 installed on the positive terminal post 2 is made of a different material than the reinforcing piece 5 installed on the negative terminal post 3; using the same material as the terminal post can strengthen the connection with the terminal post, increase mechanical stability and sealing, and further ensure the sealing of the battery.

[0040] Furthermore, to prevent short circuits, the outer diameter of the second insulating part 42 is larger than the outer diameter of the reinforcing piece 5, thereby preventing the reinforcing piece 5 from being electrically connected to the cover plate 1; to protrude the pole, the outer diameter of the reinforcing piece 5 is larger than the outer diameter of the first protrusion 21, and the height of the reinforcing piece 5 is lower than the height of the first protrusion 21.

[0041] As shown in Figure 4, a second insulating protrusion 421 is installed on the upper part of the second insulating part 42. The inner side of the second insulating protrusion 421 wraps the outer side of the reinforcing piece 5. The installation of the second insulating protrusion 421 can block the side of the reinforcing piece 5 from getting close to the cover plate 1, which can prevent the reinforcing piece 5 from being electrically connected to the cover plate 1, and can also prevent other cables from being electrically connected to the reinforcing piece 5 and the cover plate 1, thereby reducing the occurrence of short circuits in the lithium battery and improving the safety of the lithium battery.

[0042] Furthermore, in order to highlight the vertical position of the reinforcing piece 5, in this embodiment, the upper surface of the second insulating protrusion 421 is lower than the upper surface of the reinforcing piece 5.

[0043] The insulating part 4 adopts a multi-layer composite structure, including at least a ceramic layer and a polymer layer; wherein, the ceramic layer can ensure insulation, and the polymer layer ensures that the insulating part 4 has a certain elastic deformation ability, thereby sealing the cover plate 1 and preventing electrolyte leakage; the insulating part 4 can be a double layer, using a ceramic layer and a polymer layer, or it can be a multi-layer structure, using a polymer layer, a ceramic layer and a polymer layer stacked together in sequence.

[0044] As shown in Figure 4, the bonding method between the positive electrode post 2, the negative electrode post 3, the cover plate 1, and the insulating part 4 is either thermoforming or injection molding. Specifically, if the polymer layer in the insulating part 4 is easily melted by heat, then thermoforming can be used; if the polymer layer in the insulating part 4 is not easily melted by heat, then injection molding can be used, where the parts are assembled together during molding. This ensures a tight fit between the insulating part 4, the positive electrode post 2, the negative electrode post 3, and the cover plate 1, preventing electrolyte leakage and short circuits, and improving battery safety.

[0045] As shown in Figure 6, the upper surface of the second insulating part 42 is provided with a plurality of first sealing ring protrusions 422. The first sealing ring protrusions 422 are in contact with the bottom surface of the reinforcing sheet 5. The bottom surface of the reinforcing sheet 5 can be provided with first sealing ring grooves corresponding to the first sealing ring protrusions 422, which limit each other and prevent movement to increase sealing performance. In this embodiment, the bottom surface of the reinforcing sheet 5 directly presses the first sealing ring protrusions 422, causing the first sealing ring protrusions 422 to deform, thereby achieving sealing.

[0046] Similarly, as shown in Figure 5, the lower surface of the first insulating part 41 is provided with a plurality of second sealing ring protrusions 412. The second sealing ring protrusions 412 are in contact with the upper surface of the second protrusion 23. The upper surface of the second protrusion 23 may be provided with second sealing ring grooves corresponding to the second sealing ring protrusions 412, which limit each other and prevent movement, thereby increasing the sealing performance. In this embodiment, the upper surface of the second protrusion 23 directly presses the second sealing ring protrusions 412, causing the second sealing ring protrusions 412 to deform, thereby achieving a seal and preventing electrolyte leakage between the second protrusion 23 and the first insulating part 41.

[0047] Similarly, the inner surface of the first insulating part 41 is provided with a plurality of third sealing ring protrusions, which are in contact with the side of the vertical part 22 to prevent electrolyte leakage between the first insulating part 41 and the vertical part 22; the outer surface of the first insulating part 41 is provided with a plurality of fourth sealing ring protrusions, which are in contact with the side of the cover plate 1 to prevent electrolyte leakage between the first insulating part 41 and the cover plate 1.

[0048] Example 2

[0049] Please refer to Figures 7 to 9. This utility model provides a steel-cased battery.

[0050] As shown in Figure 7, the steel-cased battery includes a bipolar terminal cover structure for a steel-cased battery as described in Embodiment 1; it also includes a steel-cased lower cover 71, with a cover plate 1 installed at the end of the lower cover 71, and a positive terminal 2 and a negative terminal 3 arranged side by side on the cover plate 1; the steel-cased lower cover 71 can be made of low-cost steel, which is a conductive material, and may also be made of engineering plastics in the future; the positive terminal 2 is made of conductive metals such as aluminum or aluminum alloy, and the negative terminal 3 is made of conductive metals such as copper or copper alloy.

[0051] As shown in Figure 7, the lower steel shell cover 71 has an internal cavity, and a battery cell 8 is installed inside the cavity. One end of the battery cell 8 is equipped with a positive electrode tab 81 and a negative electrode tab 82. Both the positive electrode tab 81 and the negative electrode tab 82 are coated with electrode insulating adhesive 83 to ensure the insulation of the positive electrode tab 81 and the negative electrode tab 82 and prevent short circuits from contacting the lower steel shell cover 71.

[0052] Furthermore, the positive electrode tab 81 is connected to the positive electrode post 2 by welding; the negative electrode tab 82 is connected to the negative electrode post 3 by welding; a steel shell cover plate 72 is welded to the upper part of the lower steel shell cover 71, and the steel shell cover plate 72 seals the battery cell 8 and the lower steel shell cover 71, thereby forming a steel shell battery.

[0053] The battery cell 8 is covered with a diaphragm or insulating adhesive 84 to prevent the battery cell 8 from coming into contact with the steel shell cover 71 and short-circuiting.

[0054] As shown in Figure 8, the steel-cased battery can also be equipped with an injection hole. The injection hole can be located on the steel casing cover 72 or the steel casing lower cover 71. In this embodiment, the side of the steel casing lower cover 71 is equipped with an injection hole and a sealing plate 73 for sealing the injection hole.

[0055] As shown in Figure 8, the steel-cased battery is also equipped with an arc-shaped pressure relief valve 74 to ensure the safety performance of the battery cell 8. In this embodiment, the arc-shaped pressure relief valve 74 is disposed on the upper surface of the steel casing cover 72.

[0056] The inner wall of the lower steel cover 71 is coated with an insulating coating, which can further prevent the positive electrode tab 81 and the negative electrode tab 82 inside from being electrically connected to the lower steel cover 71, thus ensuring the insulation of the lower steel cover 71.

[0057] In Example 2, the bipolar square steel-cased battery was introduced in detail. Similarly, the cylindrical bipolar steel-cased battery operates on the same principle, so it will not be repeated here. The cover plate 1 can be designed to be circular.

[0058] The above embodiments are preferred embodiments of the present utility model, but the embodiments of the present utility model are not limited to the above embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present utility model shall be considered equivalent substitutions and shall be included within the protection scope of the present utility model.

Claims

1. A bipolar post cover structure for steel-cased batteries, characterized in that: The device includes a cover plate (1), which has a first through hole (11) and a second through hole (12). The first through hole (11) is equipped with a positive electrode post (2), and the second through hole (12) is equipped with a negative electrode post (3). The positive electrode post (2) and the negative electrode post (3) include a second protrusion (23) installed inside the cover plate (1), a vertical part (22) corresponding to the vertical side of the cover plate (1), and a first protrusion (21) installed outside the cover plate (1). The positive electrode post (2) and the negative electrode post (3) are insulated from the cover plate (1) by an insulating part (4). The insulating part (4) is annular. One side of the insulating part (4) wraps around the first through hole (11) and / or the second through hole (12), and the other side is inserted into the vertical part (22).

2. The bipolar post cover structure for a steel-cased battery according to claim 1, characterized in that: A negative electrode post (3) is provided on one side of the positive electrode post (2); the positive electrode post (2) and the negative electrode post (3) are arranged side by side, with at least one end at the same height.

3. The bipolar post cover structure for a steel-cased battery according to claim 1, characterized in that: The insulating part (4) includes a first insulating part (41) installed on the inner side and a second insulating part (42) installed on the outer side; the second insulating part (42) is annular and sleeved on the outer side of the first insulating part (41); the first insulating part (41) insulates the side and bottom surfaces of the first through hole (11) and / or the second through hole (12), and the second insulating part (42) insulates the upper surface of the first through hole (11) and / or the second through hole (12).

4. The bipolar post cover structure for a steel-cased battery according to claim 3, characterized in that: The lower part of the first insulating part (41) is provided with a first insulating protrusion (411), and the inner side of the first insulating protrusion (411) wraps the outer side of the second protrusion (23).

5. A bipolar post cover structure for a steel-cased battery according to claim 3, characterized in that: A reinforcing plate (5) is installed between the bottom surface of the first protrusion (21) and the insulating part (4). The inner side of the reinforcing plate (5) is in contact with the outer side of the vertical part (22). The bottom surface of the reinforcing plate (5) is in contact with the upper part of the first insulating part (41) and the upper part of the second insulating part (42), pressing the upper part of the first insulating part (41) and the upper part of the second insulating part (42) together.

6. A bipolar post cover structure for a steel-cased battery according to claim 5, characterized in that: The upper part of the second insulating part (42) is provided with a second insulating protrusion (421), and the inner side of the second insulating protrusion (421) wraps the outer side of the reinforcing sheet (5).

7. The bipolar post cover structure for a steel-cased battery according to claim 1, characterized in that: The insulating part (4) adopts a multi-layer composite structure, including at least a ceramic layer and a polymer layer; the bonding method between the positive electrode post (2), the negative electrode post (3), the cover plate (1) and the insulating part (4) is a hot-press bonding method or an injection molding method.

8. A bipolar post cover structure for a steel-cased battery according to claim 5, characterized in that: The upper surface of the second insulating part (42) is provided with a plurality of first sealing ring protrusions (422), which are in contact with the bottom surface of the reinforcing piece (5). The lower surface of the first insulating part (41) is provided with a plurality of second sealing ring protrusions (412), which are in contact with the upper surface of the second protrusion (23). The inner surface of the first insulating part (41) is provided with a plurality of third sealing ring protrusions, which are in contact with the side of the vertical part (22). The outer surface of the first insulating part (41) is provided with a plurality of fourth sealing ring protrusions, which are in contact with the side of the cover plate (1).

9. A steel-cased battery, characterized in that: The invention includes a bipolar cover plate structure for a steel-cased battery as described in any one of claims 1 to 8; it also includes a steel-cased lower cover (71), the end of which is provided with a cover plate (1), and a battery cell (8) is installed in the internal cavity of the steel-cased lower cover (71). One end of the battery cell (8) is provided with a positive electrode tab (81) and a negative electrode tab (82). The positive electrode tab (81) is connected to the positive electrode post (2) by welding; the negative electrode tab (82) is connected to the negative electrode post (3) by welding; and a steel-cased cover plate (72) is installed on the upper part of the steel-cased lower cover (71) by welding, which seals the battery cell (8) and the steel-cased lower cover (71).

10. A steel-cased battery according to claim 9, characterized in that: The side of the lower steel shell cover (71) is provided with a liquid injection hole and a sealing plate (73) for sealing the liquid injection hole. The upper surface of the steel shell cover plate (72) is provided with an arc-shaped pressure relief valve (74). The positive electrode tab (81) and the negative electrode tab (82) are both coated with tab insulating glue (83). The battery cell (8) is covered with a diaphragm or insulating glue (84). The inner wall of the lower steel shell cover (71) is coated with an insulating coating.

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