Lithium battery

Abstract

Lithium battery comprising: a housing (800) in which a receiving space is provided; a winding core arranged in the receiving space; a negative cover plate assembly arranged on a first side of the winding core; a positive cover plate assembly arranged on a second side of the winding core, the first side of the winding core being opposite the second side of the winding core, the positive cover plate assembly comprising: a busbar (100) arranged on the winding core; an insulating component (500) arranged on the busbar (100); a cover plate (200) arranged on the insulating component (500) and connected to the busbar (100), wherein a first mounting groove (210) is provided in a central region on one side of the cover plate (200) away from the busbar (100), wherein a liquid injection hole (211) is provided in a center of the first mounting groove (210);an elastic sealing ring (300) arranged in the first mounting groove (210) and surrounding the liquid injection hole (211); a positive clamp (400) attached to the first mounting groove (210) by a rivet component on the cover plate (200), wherein the positive clamp (400) compresses the elastic sealing ring (300), the positive clamp (400) sealing the liquid injection hole (211).

Description

TECHNICAL FIELD The present application relates to the technical field of lithium batteries, specifically a lithium battery. STATE OF THE ART Lithium batteries are widely used in electric vehicles, backup power systems, and microgrid energy storage systems due to their high energy density and long cycle life. Lithium batteries contain wound cores, electrolytes, casings, covers, and other structures. In the prior art, a liquid injection hole is provided on the lid of the lithium battery for injecting liquid into the lithium battery during lithium battery manufacturing. Since the liquid injection hole on the lid of the lithium battery is usually located at an eccentric position on the lid in the prior art, an operator or device must align and position the liquid injection hole before injecting liquid into the lithium battery, which leads to greater difficulties in lithium battery manufacturing. After the lithium battery injection is completed, the operator or device must weld a sealing nail to the liquid injection hole, which increases the number of processes in lithium battery manufacturing and reduces the efficiency during lithium battery production. DISCLOSURE OF THE UTILITY MODEL Embodiments of the present application provide a lithium battery aimed at solving the problem of low production efficiency of lithium batteries. In a first aspect, embodiments of the present application provide a lithium battery comprising: a housing in which a receiving space is provided; a winding core arranged in the receiving space; a negative cover plate assembly arranged on a first side of the winding core; a positive cover plate assembly arranged on a second side of the winding core, the first side of the winding core being opposite the second side of the winding core, the positive cover plate assembly comprising: a collecting plate arranged on the winding core; an insulating component arranged on the collecting plate;a cover plate disposed on the insulating component and connected to the header plate, wherein a first mounting groove is provided in a central region on a side of the cover plate away from the header plate, wherein a liquid injection hole is provided in a center of the first mounting groove; an elastic sealing ring disposed in the first mounting groove and surrounding the liquid injection hole; a positive clamp fixed to the first mounting groove by a rivet component on the cover plate, and wherein the positive clamp compresses the elastic sealing ring; In a second aspect, embodiments of the present application provide a battery module comprising the above-mentioned lithium battery. Beneficial effects In the exemplary embodiment of the application, a lithium battery is provided, comprising: a housing, a winding core, a negative cover plate assembly, and a positive cover plate assembly; wherein a receiving space is provided in the housing; wherein the winding core is arranged in the receiving space; wherein the negative cover plate assembly is arranged on a first side of the winding core; wherein the positive cover plate assembly is arranged on a second side of the winding core, wherein the first side of the winding core is opposite the second side of the winding core, wherein the positive cover plate assembly comprises: a collecting plate, an insulating component, a cover plate, an elastic sealing ring, and a positive terminal; wherein the collecting plate is arranged on the winding core; wherein the insulating component is arranged on the collecting plate;wherein the cover plate is arranged on the insulating component and is connected to the collecting plate, wherein a first mounting groove is provided in a central region on a side of the cover plate away from the collecting plate, wherein a liquid injection hole is provided in the center of the first mounting groove; wherein the elastic sealing ring is arranged in the first mounting groove, and wherein the elastic sealing ring surrounds the liquid injection hole; wherein the positive clamp is fastened to the first mounting groove by a rivet component on the cover plate, and wherein the positive clamp compresses the elastic sealing ring, wherein the positive clamp seals the liquid injection hole;Since the first mounting groove is located in the central region of the cover plate and the liquid injection hole is located in the center of the mounting groove, the liquid injection hole is located in the center of the cover plate, so that no alignment is required when filling the lithium battery with liquid; this can reduce the difficulty of manufacturing lithium batteries; at the same time, the elastic sealing ring is arranged around the liquid injection hole, and the positive clamp is arranged on the first mounting groove, and the positive clamp presses the elastic sealing ring together, so that the positive clamp and the elastic sealing ring can form a sealing structure for sealing the liquid injection hole without the need for additional soldering of sealing nails on the liquid injection hole, thereby reducing the production process of lithium batteries and improving the production efficiency of lithium batteries. DESCRIPTION OF THE CHARACTERS Fig. 1 is an exploded view of the positive cover plate assembly in the present application; Fig. 2 is a sectional view of the positive cover plate assembly when the positive terminal is not fixed in the present application; Fig. 3 is a sectional view of the positive cover plate assembly when the positive terminal is fixed in the present application; Fig. 4 is an enlarged view of position A in Fig. 3; Fig. 5 is an enlarged view of position B in Fig. 3; Fig. 6 is a structural diagram of the insulating component in the present application; Fig. 7 is a structural diagram of the bus bar in the present application; Fig. 8 is a structural diagram of the lithium battery in the present application; 100. Header plate, 110. Header section, 120. Connecting section; 200. Cover plate, 210. First mounting groove, 211. Liquid injection hole, 212. Annular projection, 2121. Vertical part, 2122. Horizontal part, 220. Through hole, 230. Groove; 300. Elastic seal ring; 400. Positive terminal, 410. Protrusion, 420. Third mounting groove; 500. Insulating component, 510. Second mounting groove; 520. Orifice; 600. Explosion-proof valve; 700. Protective film for the explosion-proof valve; 800. Casing. SPECIFIC EMBODIMENTS In the prior art, a liquid injection hole is provided on the lid of the lithium battery for injecting liquid into the lithium battery during lithium battery manufacturing. Since the liquid injection hole on the lid of the lithium battery is usually located at an eccentric position on the lid in the prior art, an operator or device must align and position the liquid injection hole before injecting liquid into the lithium battery, which leads to greater difficulties in lithium battery manufacturing. After the lithium battery injection is completed, the operator or device must weld a sealing nail to the liquid injection hole, which increases the number of processes in lithium battery manufacturing and reduces the efficiency during lithium battery production.Therefore, a first embodiment of the present application provides a battery module including a lithium battery. Referring to FIGS. 1, 2, 3, and 8, the lithium battery includes a housing 800, a winding core, a negative cover plate assembly, and a positive cover plate assembly. Specifically, the housing 800 is provided with a receiving space, wherein the winding core is arranged in the receiving space and the negative cover plate assembly is arranged on the first side of the winding core; wherein the positive cover plate assembly is arranged on a second side of the winding core, wherein the first side of the winding core is opposite the second side of the winding core. Furthermore, the positive cover plate assembly includes: a collecting plate 100, an insulating component 500, a cover plate 200, an elastic sealing ring 300, and a positive clamp 400; wherein the collecting plate 100 is arranged on the winding core; wherein the insulating component 500 is provided on the collecting plate 100; The cover plate 200 is arranged on the insulating component 500, and wherein the cover plate 200 is connected to the collecting plate 100, wherein a first mounting groove 210 is provided in a central region on a side of the cover plate 200 away from the collecting plate 100, wherein a liquid injection hole 211 is provided in the center of the first mounting groove 210; wherein the elastic sealing ring 300 is arranged in the first mounting groove 210, and wherein the elastic sealing ring 300 is arranged around the liquid injection hole 211; wherein the positive clamp 400 is fastened to the first mounting groove 210 by the rivet component on the cover plate 200, and wherein the positive clamp 400 compresses the elastic sealing ring 300. By disposing the first mounting groove 210 in the central region of the cover plate 200, the liquid injection hole 211 is located in the center of the first mounting groove 210, so that the liquid injection hole 211 is located in the center of the cover plate 200, so that no alignment is required when filling the lithium battery with liquid; thereby reducing the difficulty in manufacturing the lithium batteries.At the same time, the elastic sealing ring 300 is arranged around the liquid injection hole 211, and the positive clamp 400 is arranged on the first mounting groove 210. The positive clamp 400 compresses the elastic sealing ring 300, so that the positive clamp 400 and the elastic sealing ring 300 can form a sealing structure for sealing the liquid injection hole 211 without the need for additional soldering of sealing nails to the liquid injection hole 211, thereby reducing the production process of the lithium batteries and improving the production efficiency of the lithium batteries. And since sealing nails are not required for the solution-type lithium battery, the number of positive cover plate assemblies is reduced, thereby reducing the production cost of the positive cover plate assemblies. Referring to Fig. 7, the header plate 100 in the present embodiment includes a header portion 110 and a connecting portion 120 located on one side of the header portion 110, the connecting portion 120 passing through the insulating component 500 and connected to the cover plate 200. In the present embodiment, it is provided that the insulating component 500 is a silica gel plate. In the present embodiment, it is provided that the elastic sealing ring 300 is a rubber ring or a silica gel ring. In the present embodiment, it is provided that the underside of the positive terminal 400 is provided with a third mounting groove 420, wherein the third mounting groove 420 is connected to the first mounting groove 210, wherein a part of the elastic sealing ring 300 lies in the first mounting groove 210 and the other part of the elastic sealing ring 300 lies in the third mounting groove 420. In the present embodiment, it is provided that the first mounting groove 210 and the third mounting groove 420 are both circular. 2 to 4, in one embodiment, the rivet component includes an annular projection 212 extending from a bottom surface of the first mounting groove 210 in a direction away from the header plate 100, the annular projection 212 being bent toward the center of the liquid injection hole 211, a restricting groove (not marked in the figure) being formed between the annular projection 212 and the first mounting groove 210, the positive terminal having a protrusion 410 extending from a peripheral side wall of the positive terminal 400 toward the restricting groove, the protrusion 410 being inserted into the restricting groove.By disposing the annular projection 212, the annular projection 212 is bent toward the center of the liquid injection hole 211 so that a restricting groove is formed between the annular projection 212 and the first mounting groove 210, and meanwhile, a protrusion 410 is provided on the peripheral side wall of the positive terminal 400 extending toward the restricting groove so that the protrusion 410 can be inserted into the restricting groove, thereby ensuring that the positive terminal 400 can be riveted and fixed in the first mounting groove 210. In the present embodiment, the annular projection 212 is provided to extend entirely from the bottom surface of the first mounting groove 210 away from the collecting plate 100, and correspondingly, the elevation 410 extends entirely from the peripheral side wall of the positive terminal 400 toward the limiting groove. In the present embodiment, it is provided that the annular projection 212 comprises a plurality of spaced-apart first projecting portions, wherein a first recess is formed between two adjacent first projecting portions, and accordingly, the elevation 410 comprises a plurality of spaced-apart second projecting portions, wherein a second recess is formed between two adjacent second projecting portions, and at this time, a restricting groove is formed between the first projecting portion and the first mounting groove 210, wherein the first projecting portion lies in the restricting groove. In the present embodiment, it is provided that the annular projection 212 includes a plurality of spaced-apart first protruding portions, a first recess is formed between two adjacent first protruding portions, the projection 410 extends entirely from the peripheral side wall of the positive terminal 400 toward the restricting groove, and at this time, the restricting groove is formed between the first protruding portion and the first mounting groove 210, and the projection 410 is located in the restricting groove. In the present embodiment, it is provided that the annular projection 212 extends completely from the bottom surface of the first mounting groove 210 toward the collecting plate 100, wherein the elevation 410 comprises: a plurality of second projecting portions arranged at intervals, wherein a second recess is formed between two adjacent second projecting portions, and at this time, a limiting groove is formed between the annular projection 212 and the first mounting groove 210, wherein the second projecting portion lies in the limiting groove. In the present embodiment, referring to Fig. 4, the annular protrusion 212 includes a vertical part 2121 and a horizontal part 2122; the vertical part 2121 is connected to the first mounting groove 210; the horizontal part 2122 is connected to the vertical part 2121, and the bottom surface of the horizontal part 2122 is in close contact with the top surface of the protrusion 410. By arranging the bottom surface of the horizontal part 2122 to closely contact the top surface of the protrusion 410, it is ensured that the connection between the annular protrusion 212 and the protrusion 410 can be sealed, thereby further sealing the liquid injection hole 211. In the present embodiment, both the bottom surface of the horizontal part 2122 and the top surface of the protrusion 410 are flat surfaces. Making the bottom surface of the horizontal part 2122 and the top surface of the protrusion 410 flat ensures a better fit between the bottom surface of the horizontal part 2122 and the top surface of the protrusion 410. When assembling the positive cover plate assembly, first, the insulating component 500 is mounted on the header plate 100, and at the same time, the connecting portion 120 on the header plate 100 is passed through the opening 520 on the insulating component 500 so that the connecting portion 120 of the header plate 100 can be arranged on the head surface of the insulating component 500, and then the explosion-proof valve 600 is mounted in the second mounting groove 510, and then the cover plate 200 is attached to the header plate 100, and it is ensured that the cover plate 200 is connected to the header plate 100.Next, the elastic seal ring 300 and the positive terminal 400 are successively placed on the first mounting groove 210 to ensure that the protrusion 410 on the positive terminal 400 can be positioned within the area formed by the annular projection 212. At the same time, a force is applied to the positive terminal 400 to compress the elastic seal ring 300 while ensuring that the horizontal plane of the protrusion 410 is lower than the horizontal plane of the annular projection 212. Finally, the annular projection 212 is bent toward the liquid injection hole 211 and restricts the protrusion 410, thereby completing the assembly of the lithium battery. In the present embodiment, the thickness of the annular projection 212 is configured to be 0.5 mm to 1 mm.By setting the thickness of the annular protrusion 212 to 0.5 mm to 1 mm, the strength of the annular protrusion 212 can be ensured and deformation due to the thinness of the annular protrusion 212 can be avoided when the annular protrusion 212 is subjected to excessive compressive force. Preferably, the thickness of the annular protrusion 212 is 0.5 mm, 0.8 mm, or 1 mm. In the present embodiment, it is provided that the thickness of the protrusion 410 is not less than 0.5 mm, and the length of the protrusion 410 is not less than 5 mm. By setting the thickness of the protrusion 410 to not less than 0.5 mm, the strength of the protrusion 410 can be ensured, and thereby the protrusion 410 is prevented from being deformed due to an excessive compressive force caused by an insufficient thickness of the protrusion 410. Meanwhile, the length of the protrusion 410 is set to not less than 5 mm to prevent the length of the protrusion 410 from being too small and the contact area between the protrusion 410 and the horizontal part 2122 from being too small, which results in the sealing performance of the sealing structure of the liquid injection hole 211 being reduced. Preferably, the thickness of the protrusion 410 is set to 0.5 mm, 0.75 mm, or 0.8 mm; the length of the elevation 410 is 5 mm, 6 mm or 8 mm. In the present embodiment, the distance between the side wall of the first mounting groove 210 and the annular projection 212 is 5 mm to 20 mm. Preferably, the distance between the side wall of the first mounting groove 210 and the annular projection 212 is 6 mm, 10 mm, or 18 mm. In the present embodiment, the height of the positive terminal 400 is 2 mm to 3 mm. Preferably, the height of the positive terminal 400 is 2 mm, 2.5 mm, or 2.8 mm. In the present embodiment, the distance between the head surface of the positive terminal 400 and the head surface of the third mounting groove 420 is not less than 1 mm. Preferably, the distance between the head surface of the positive terminal 400 and the head surface of the third mounting groove 420 is 2 mm, 3 mm, or 4 mm. In the present embodiment, it is provided that the depth of the third mounting groove is 1 mm to 3 mm. In the present embodiment, the compression ratio of the elastic sealing ring 300 is set to be 15% to 45%. Setting the compression ratio of the elastic sealing ring 300 to 15%-45% ensures that the elastic sealing ring 300 can generate sufficient elastic force to compress the positive clamp 400, ensuring that the bottom surface of the horizontal part 2122 is in close contact with the top surface of the protrusion 410. In the present embodiment, with reference to Fig. 3, Fig. 5 and Fig. 6, it is provided that the lithium battery also includes an explosion-proof valve 600, wherein a second mounting groove 510 is provided on a side of the insulating component 500 facing the cover plate 200, and the explosion-proof valve 600 is mounted in the second mounting groove 510. By adjusting the explosion-proof valve 600, the explosion-proof valve 600 can be opened when the internal pressure of the lithium battery is too high to release the gas in the lithium battery and thus reduce the internal pressure of the battery, thereby reducing the risk of explosion or leakage of the lithium battery. In the present embodiment, it is provided that an opening 520 is also provided in the insulating component 500, and the connecting portion 120 of the collecting plate 100 extends through the opening 520 and is connected to the underside of the cover plate 200. In the present embodiment, with reference to FIGS. 3, 5, and 6, the lithium battery is also provided with a protective film 700 for the explosion-proof valve. The cover plate 200 is further provided with a through-hole 220, the position of the through-hole 220 corresponding to the position of the second mounting groove 510. The protective film 700 for the explosion-proof valve is arranged on a side of the through-hole 220 away from the explosion-proof valve 600. By providing the protective film 700 for the explosion-proof valve, dust, liquid, or other contaminants can be prevented from entering the explosion-proof valve 600 through the through-hole 220, thereby ensuring the smooth operation of the explosion-proof valve 600 to prevent the explosion-proof valve 600 from being affected by the external environment and from malfunctioning. In the present embodiment, a groove 230 is provided on a side of the cover plate 200 away from the explosion-proof valve 600, the groove 230 being arranged around the through hole 220, and the groove 230 being connected to the through hole 220, and the explosion-proof valve protective film 700 being arranged in the groove 230. Sealing principle of the liquid injection hole: Since the positive clamp 400 is riveted into the first mounting groove 210, the positive clamp 400 is in a rotatable state at this time. When the elastic seal ring 300 and the positive clamp 400 are assembled, the elastic seal ring 300 is pressed by the positive clamp 400, so that the bottom surface of the elastic seal ring 300 can be tightly abutted against the bottom surface of the first mounting groove 210 to form a first sealing portion for sealing the liquid injection hole 211 at one time. Since the elastic seal ring 300 is simultaneously compressed by the positive clamp 400, the elastic seal ring 300 has elastic potential energy.Under the action of the elastic sealing ring 300, the positive clamp 400 tends to move away from the elastic sealing ring 300, whereby the top surface of the protrusion 410 can be in close contact with the bottom surface of the horizontal part on the annular projection 212 to form a second sealing area for secondary sealing of the liquid injection hole.

Claims

A lithium battery, comprising: a housing (800) in which a receiving space is provided; a winding core arranged in the receiving space; a negative cover plate assembly arranged on a first side of the winding core; a positive cover plate assembly arranged on a second side of the winding core, the first side of the winding core being opposite the second side of the winding core, the positive cover plate assembly comprising: a collecting plate (100) arranged on the winding core; an insulating component (500) arranged on the collecting plate (100); a cover plate (200) arranged on the insulating component (500) and connected to the collecting plate (100), wherein a first mounting groove (210) is provided in a central region on a side of the cover plate (200) away from the collecting plate (100), wherein a liquid injection hole (211) is provided in a center of the first mounting groove (210);an elastic sealing ring (300) arranged in the first mounting groove (210) and surrounding the liquid injection hole (211); a positive clamp (400) fastened to the first mounting groove (210) by a rivet component on the cover plate (200), and wherein the positive clamp (400) compresses the elastic sealing ring (300), the positive clamp (400) sealing the liquid injection hole (211); A lithium battery according to claim 1, wherein the rivet component comprises an annular projection (212) extending from a bottom surface of the first mounting groove (210) in a direction away from the collecting plate (100), the annular projection (212) being bent towards the center of the liquid injection hole (211), a restricting groove being formed between the annular projection (212) and the first mounting groove (210), the positive terminal (400) having a protrusion (410) extending from a peripheral side wall of the positive terminal (400) toward the restricting groove, the protrusion (410) being inserted into the restricting groove. A lithium battery according to claim 2, wherein the annular projection (212) comprises:a vertical part (2121) connected to the first mounting groove (210);a horizontal part (2122) connected to the vertical part (2121), wherein a bottom surface of the horizontal part (2122) is in close contact with a top surface of the projection (410). A lithium battery according to claim 3, wherein both the bottom surface of the horizontal part (2122) and the top surface of the elevation (410) are flat surfaces. A lithium battery according to any one of claims 2 to 4, wherein a thickness of the annular projection (212) is 0.5 mm to 1 mm. A lithium battery according to claim 5, wherein a thickness of the annular projection (212) is 0.5 mm, 0.8 mm or 1 mm. A lithium battery according to any one of claims 2 to 6, wherein a thickness of the protrusion (410) is not less than 0.5 mm, and a length of the protrusion (410) is not less than 5 mm. Lithium battery according to claim 7, wherein the thickness of the elevation (410) is 0.5 mm, 0.75 mm or 0.8 mm, and the length of the elevation (410) is 5 mm, 6 mm or 8 mm. A lithium battery according to any one of claims 2 to 8, wherein a distance between a side wall of the first mounting groove (210) and the annular projection (212) is 5 mm to 20 mm. Lithium battery according to claim 9, wherein the distance (212) between the side wall of the first mounting groove (210) and the annular projection (212) is 6 mm, 10 mm or 18 mm. Lithium battery according to one of claims 1 to 10, wherein a height of the positive terminal (400) is 2 mm to 3 mm. Lithium battery according to claim 11, wherein the height of the positive terminal (400) is 2 mm, 2.5 mm or 2.8 mm. Lithium battery according to one of claims 1 to 12, wherein a compression ratio of the elastic sealing ring (300) is 15% to 45%. A lithium battery according to any one of claims 1 to 13, wherein the lithium battery further comprises an explosion-proof valve (600), wherein a second mounting groove (510) is provided on a side of the insulating component (500) close to the cover plate (200), wherein the explosion-proof valve (600) is mounted in the second mounting groove (510). The lithium battery according to claim 14, wherein the lithium battery further comprises a protective film for the explosion-proof valve (700), wherein the cover plate (200) is further provided with a through-hole (220), a position of the through-hole (220) corresponding to the position of the second mounting groove (510), wherein the protective film for the explosion-proof valve (700) is arranged on a side of the through-hole (220) away from the explosion-proof valve (600). A lithium battery according to claim 15, wherein a groove (230) is provided on a side of the cover plate (200) away from the explosion-proof valve (600), the groove (230) being arranged around the through-hole (220) and being connected to the through-hole (220), the protective film for the explosion-proof valve (700) being arranged in the groove (230). Lithium battery according to one of claims 1 to 16, wherein the collecting plate (100) comprises a collecting section (110) and a connecting section (120) located on one side of the collecting section (110), wherein the connecting section (120) extends through the insulating component (500) and is connected to the cover plate (200). Lithium battery according to claim 17, wherein the insulating component (500) is further provided with an opening (520), wherein the connecting portion (120) of the collecting plate (100) extends through the opening (520) and is connected to an underside of the cover plate (200). Lithium battery according to one of claims 1 to 18, wherein a bottom of the positive terminal (400) is provided with a third mounting groove (420), the third mounting groove (420) being connected to the first mounting groove (210), a part of the elastic sealing ring (300) being located in the first mounting groove (210), and the other part of the elastic sealing ring (300) being located in the third mounting groove (420). A battery module comprising a lithium battery according to any one of claims 1 to 19.

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