End cover assembly, energy storage device and electric equipment

Abstract

The utility model provides an end cover assembly, an energy storage device and electric equipment. The end cover assembly can prevent laser from burning upper plastic. The end cover assembly comprises a cover plate, a pole, upper plastic, a pressing ring and a welding part. The cover plate is provided with an assembling hole penetrating through the first surface and the second surface. The pressing ring is located on the side, away from the second surface, of the first surface, a pressing ring body of the pressing ring is provided with a matching hole penetrating through the third surface and the fourth surface, and the protruding part of the pressing ring is arranged on the hole wall face of the matching hole. The pole penetrates through the assembling hole and the matching hole, an opening of a groove of the pole is located in the surface, deviating from the first surface, of the pole, the groove penetrates through the peripheral side face of the pole, and the protruding part is installed in the groove and welded to the groove wall face of the groove; the welding part is positioned on one side, facing the fourth surface, of the third surface, is positioned on one side, facing the groove wall surface of the groove, of the protruding part, and is connected to the pole; and the upper plastic cement is positioned on one side, deviating from the fourth surface, of the third surface, penetrates through the assembly hole, is arranged around the pole column and is also positioned between the pole column and the cover plate.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of energy storage, in particular to an end cover assembly, an energy storage device and an electric equipment. BACKGROUND

[0002] A secondary battery, also known as a rechargeable battery or a storage battery, refers to a battery that can be activated by charging after discharging to continue to be used. The recyclable feature of the secondary battery makes it gradually become the main power source of electric equipment. With the gradual increase in demand for secondary batteries, people's requirements for the performance of the energy density and use reliability of the secondary battery are also increasing. However, in the existing secondary battery, when the compression ring and the pole of the end cover assembly are laser welded, the laser is easy to enter the assembly gap between the pole and the compression ring, which causes the upper plastic to be burned by the laser, thereby reducing the production yield of the end cover assembly. CONTENT OF THE UTILITY MODEL

[0003] The present application provides an end cover assembly, an energy storage device and an electric equipment, which can prevent the upper plastic from being burned by laser when the pole and the compression ring are welded, thereby helping to improve the welding yield of the end cover assembly.

[0004] In a first aspect, the application provides an end cover assembly for an energy storage device. The end cover assembly comprises a cover plate, a pole, an upper plastic, and a compression ring. The cover plate comprises a first surface and a second surface, which are oppositely arranged along the thickness direction of the cover plate. The cover plate is provided with an assembly hole, which penetrates the first surface and the second surface. The compression ring is located on the side of the first surface away from the second surface. The compression ring comprises a compression ring body and a protruding portion. The compression ring body comprises a third surface and a fourth surface, which are oppositely arranged along the thickness direction of the compression ring body. The third surface faces the cover plate. The compression ring body is provided with a matching hole, which penetrates the third surface and the fourth surface and communicates with the assembly hole. The protruding portion is arranged around the center of the matching hole and is located on the side of the third surface away from the fourth surface. The pole is arranged in the assembly hole and the matching hole. The pole is provided with a groove. The opening of the groove is located on the surface of the pole away from the first surface. The groove penetrates the surface of the pole facing the hole wall surface of the matching hole and is arranged around the pole. The protruding portion is mounted in the groove and is welded to the groove wall surface and arranged around the pole. The welding portion is located on the side of the third surface away from the fourth surface and on the side of the protruding portion away from the groove wall surface of the groove and is connected to the pole. The upper plastic is located on the side of the third surface away from the fourth surface and is arranged in the assembly hole. The upper plastic is arranged around the pole and is located between the pole and the cover plate.

[0005] The pole comprises a welding surface, which is located on the side of the first surface away from the second surface and is used for welding with an adapter sheet of the energy storage device. The groove wall surface comprises a first groove wall surface and a second groove wall surface. The first groove wall surface is located on the side of the peripheral surface of the pole away from the hole wall surface of the matching hole. The second groove wall surface is oppositely arranged with the opening of the groove and is connected between the peripheral surface of the pole and the first groove wall surface. The distance between the second groove wall surface and the welding surface gradually decreases from the peripheral surface of the pole to the first groove wall surface. The protruding portion comprises a fifth surface, a first side surface, and a second side surface, which are sequentially connected. The first side surface faces the first groove wall surface and is welded to the first groove wall surface. The second side surface is connected between the hole wall surface of the matching hole and the first side surface and faces the second groove wall surface and is welded to the second groove wall surface. The fifth surface is the surface of the protruding portion away from the cover plate. The distance between the second side surface and the fifth surface gradually decreases from the hole wall surface of the matching hole to the first side surface.

[0006] The distance between the second groove wall surface and the welding surface is constant from the circumferential surface of the pole column to the first groove wall surface.

[0007] The pole column comprises a fixed part and a fitting part connected with each other, the fitting part is arranged in the assembly hole, the fixed part is located on the side of the first surface away from the second surface and is fixedly connected with the fitting part and arranged in the assembly hole, the fixed part comprises the welding surface, the fixed part is provided with the groove, the opening of the groove is located on the welding surface, the groove penetrates through the circumferential surface of the fixed part and surrounds the fixed part, and the circumferential surface of the fitting part is protruded relative to the circumferential surface of the fixed part.

[0008] The third surface is provided with a protruding rib, the protruding rib is arranged around the assembly hole and abuts against the surface of the fitting part facing the fixed part.

[0009] The protruding rib is provided with a notch, the notch penetrates through the protruding rib along the width direction of the protruding rib.

[0010] The compression ring body is further provided with a positioning groove, the opening of the positioning groove is located on the fourth surface, the positioning groove is arranged around the protruding part and is spaced apart from the protruding part, and the positioning groove is correspondingly arranged with the protruding rib along the thickness direction of the compression ring body.

[0011] The pole column further comprises a flange part and a chamfer part, the flange part and the chamfer part are located on the side of the fitting part away from the fixed part, the chamfer part is connected between the flange part and the fitting part, and the diameter of the chamfer part gradually decreases from the flange part to the fitting part; the inner circumferential surface of the upper plastic comprises a first part, a second part, a third part and a fourth part, the first part faces the circumferential surface of the fitting part and surrounds the fitting part, the second part is connected on one side of the first part and faces the circumferential surface of the chamfer part and surrounds the chamfer part along the thickness direction of the end cover assembly, the third part is connected on the side of the second part away from the first part and faces the surface of the flange part facing the cover plate and surrounds the chamfer part, and the fourth part is connected on the side of the third part away from the second part and faces the circumferential surface of the flange part and surrounds the flange part, wherein the diameter of the second part gradually decreases from the third part to the first part.

[0012] The pole post comprises a first metal part and a second metal part. The first metal part is located on one side of the second metal part along the thickness direction of the end cover assembly and covers the surface of the second metal part facing the first metal part. The first metal part is provided with the groove, and the peripheral side surface of the first metal part comprises the peripheral side surface of the chamfered part.

[0013] The fourth surface and the fifth surface are both located on the side of the welding surface facing the first surface along the thickness direction of the end cover assembly.

[0014] In a second aspect, the present application further provides an energy storage device comprising a housing and the end cover assembly according to any one of the above, wherein the end cover assembly is mounted on the housing and seals the opening of the housing.

[0015] In a third aspect, the present application further provides an electric device comprising the energy storage device according to the above, wherein the energy storage device supplies power to the electric device.

[0016] In the end cover assembly provided by the present application, the protruding part is arranged on the compression ring and the groove is arranged on the pole post, and the protruding part is located in the groove. On the one hand, the leakage path of the laser in the assembly gap between the pole post and the compression ring can be extended, and the upper plastic can be prevented from being burned by the laser, so that the welding burst point problem caused by the upper plastic being burned by the hot melt can be avoided, and the welding yield of the compression ring and the pole post can be improved, and the scrap rate of the energy storage device process can be reduced. On the other hand, the area of the fitting surface of the compression ring and the pole post can be increased, and the assembly reliability between the pole post and the compression ring can be improved. On this basis, by locating the protruding part on the side of the third surface facing the fourth surface, the surface of the compression ring facing the cover plate can be distributed in a stepped manner, so that the leakage path of the laser in the assembly gap between the pole post and the compression ring can be further extended, and the upper plastic can be further prevented from being burned by the laser, so that the welding burst point problem caused by the upper plastic being burned by the hot melt can be further prevented, the welding yield of the compression ring and the pole post can be improved, and the scrap rate of the energy storage device process can be further reduced. BRIEF DESCRIPTION OF DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required to be used by the embodiments of the present application will be described below.

[0018] Figure 1 is a structural schematic diagram of an energy storage device provided by the embodiments of the present application;

[0019] Figure 2 is a structural schematic diagram of an end cover assembly in the energy storage device shown in Figure 1

[0020] Figure 3 is an exploded structural schematic diagram of the end cover assembly shown in Figure 2 ​​

[0021] Figure 4 Figure 1 is a perspective view of an end cap assembly according to the present application; Figure 2 Figure 2 is a cross-sectional view of the end cap assembly shown in Figure 1 taken along line A-A in a first embodiment;

[0022] Figure 5 Figure 3 is a cross-sectional view of the lower plastic in the end cap assembly shown in Figure 1 taken along line B-B in another embodiment; Figure 3 Figure 4 is a cross-sectional view of the end cap assembly shown in Figure 1 taken along line C-C in another embodiment;

[0023] Figure 6 Figure 5 is a cross-sectional view of the upper plastic in the end cap assembly shown in Figure 1 taken along line D-D in another embodiment; Figure 3 Figure 6 is a cross-sectional view of the end cap assembly shown in Figure 1 taken along line E-E in another embodiment;

[0024] Figure 7 Figure 7 is a cross-sectional view of the end cap assembly shown in Figure 1 taken along line F-F in another embodiment; Figure 3 Figure 8 is an exploded view of the pole unit in the end cap assembly shown in Figure 1 ;

[0025] Figure 8 Figure 9 is a cross-sectional view of the upper plastic in the pole unit shown in Figure 1 taken along line G-G in another embodiment; Figure 7 Figure 10 is a cross-sectional view of the pole in the pole unit shown in Figure 1 taken along line H-H in another embodiment;

[0026] Figure 9 Figure 11 is a cross-sectional view of the pressure ring in the pole unit shown in Figure 1 taken along line I-I in another embodiment; Figure 7 Figure 12 is a cross-sectional view of the end cap assembly shown in Figure 1 taken along line J-J in another embodiment;

[0027] Figure 10 Figure 13 is a cross-sectional view of the end cap assembly shown in Figure 1 taken along line K-K in another embodiment; Figure 7 Figure 14 is a cross-sectional view of the pressure ring in the end cap assembly shown in Figure 1 taken along line L-L in another embodiment;

[0028] Figure 11 Figure 15 is a cross-sectional view of the end cap assembly shown in Figure 1 taken along line M-M in another embodiment; Figure 10 Figure 16 is a cross-sectional view of the pressure ring in the end cap assembly shown in Figure 1 taken along line N-N in another embodiment;

[0029] Figure 12 Figure 17 is a cross-sectional view of the end cap assembly shown in Figure 1 taken along line O-O in another embodiment; Figure 10 Figure 18 is a cross-sectional view of the pressure ring in the end cap assembly shown in Figure 1 taken along line P-P in another embodiment;

[0030] Figure 13 Figure 19 is a cross-sectional view of the end cap assembly shown in Figure 1 taken along line Q-Q in another embodiment; Figure 4 Figure 20 is a cross-sectional view of the end cap assembly shown in Figure 1 taken along line R-R in another embodiment;

[0031] Figure 14 Figure 21 is a cross-sectional view of the end cap assembly shown in Figure 1 taken along line S-S in another embodiment; Figure 2 Figure 22 is a cross-sectional view of the end cap assembly shown in Figure 1 taken along line T-T in another embodiment;

[0032] Figure 15 Figure 23 is a cross-sectional view of the end cap assembly shown in Figure 1 taken along line U-U in another embodiment; Figure 14 Figure 24 is a cross-sectional view of the pole in the end cap assembly shown in Figure 1 taken along line V-V in another embodiment;

[0033] Figure 16 Figure 25 is a cross-sectional view of the pressure ring in the end cap assembly shown in Figure 1 taken along line W-W in another embodiment; Figure 14 Figure 26 is a cross-sectional view of the end cap assembly shown in Figure 1 taken along line X-X in another embodiment;

[0034] Figure 17 Figure 27 is a cross-sectional view of the end cap assembly shown in Figure 1 taken along line Y-Y in another embodiment;Figure 2 A cross-sectional structure schematic diagram of the end cover assembly shown is cut along A-A in the third embodiment;

[0035] Figure 18 is Figure 17 A cross-sectional structure schematic diagram of the pole in the end cover assembly shown is cut along A-A in the third embodiment;

[0036] Figure 19 is Figure 17 A structure schematic diagram of the upper plastic in the end cover assembly shown is cut along A-A in the third embodiment;

[0037] Figure 20 is Figure 19 A cross-sectional structure schematic diagram of the upper plastic shown is cut along E-E.

[0038] The corresponding names of the various reference signs in the drawings are as follows:

[0039] energy storage device 100, housing 110, end cover assembly 120, lower plastic 10, cover plate 20, explosion-proof valve 30, pole unit 40, first mounting surface 10a, second mounting surface 10b, explosion-proof fence 101, liquid inlet hole 102, through hole 103, first surface 20a, second surface 20b, explosion-proof hole 201, liquid injection hole 202, assembly hole 203, upper plastic 41, pole 42, sealing element 43, compression ring 44, mounting hole 411, matching groove 412, main body part 413, extension part 414, flange part 42c, matching part 42b, fixed part 42a, welding surface 422, groove 421, first groove wall surface 421a, second groove wall surface 421b, first metal part 423, second metal part 424, compression ring body 44a, protruding part 44b, third surface 441, fourth surface 442, matching hole 448, first side surface 445, second side surface 446, fifth surface 447, protruding rib 443, notch 443a, positioning groove 444, chamfer part 42d, first part 41a, second part 41b, third part 41c, fourth part 41d, fusion part 45. DETAILED DESCRIPTION

[0040] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application.

[0041] Please refer to Figure 1 , Figure 1 is a structure schematic diagram of an energy storage device 100 provided by the embodiments of the present application. In order to facilitate description, the length direction of the energy storage device 100 is defined as the X-axis direction, the width direction of the energy storage device 100 is defined as the Y-axis direction, and the height direction of the energy storage device 100 is defined as the Z-axis direction, and the X-axis direction, the Y-axis direction and the Z-axis direction are perpendicular to each other.

[0042] The energy storage device 100 includes a housing 110, an electric cell (not shown in the figure) and a cover assembly 120. The housing 110 has an opening (not shown in the figure) and a receiving cavity (not shown in the figure), and the opening communicates with the receiving cavity. The electric cell is received in the receiving cavity. The receiving cavity is also used to receive electrolyte, and the electric cell is soaked in the electrolyte. The cover assembly 120 is installed on the housing 110 and seals the opening of the housing 110. Exemplarily, the energy storage device 100 is a square battery. In some other embodiments, the energy storage device 100 can also be a cylindrical battery or other batteries.

[0043] Referring to Figures 2 to 4 , Figure 2 is a structural schematic view of the cover assembly 120 in the energy storage device 100 shown in Figure 1 , Figure 3 is an exploded structural schematic view of the cover assembly 120 shown in Figure 2 , Figure 4 is a sectional structural schematic view of the cover assembly 120 along A-A in the first embodiment shown in Figure 2 ,

[0044] The cover assembly 120 includes a lower plastic 10, a cover plate 20, an explosion-proof valve 30 and two pole units 40. The lower plastic 10 is installed on one side of the cover plate 20 in the thickness direction. The explosion-proof valve 30 and the two pole units 40 are both installed on the cover plate 20. Among them, along the length direction of the energy storage device 100, the two pole units 40 are respectively located on the opposite sides of the explosion-proof valve 30.

[0045] Referring to Figure 4 and Figure 5 , Figure 5 is a structural schematic view of the lower plastic 10 in the cover assembly 120 shown in Figure 3 ,

[0046] The lower plastic 10 includes a first mounting surface 10a and a second mounting surface 10b, and the first mounting surface 10a and the second mounting surface 10b are oppositely arranged in the thickness direction of the lower plastic 10. Among them, the first mounting surface 10a is the surface of the lower plastic 10 facing the housing 110, and the second mounting surface 10b is the surface of the lower plastic 10 away from the housing 110. The lower plastic 10 also includes an explosion-proof fence 101, and the explosion-proof fence 101 penetrates the first mounting surface 10a and the second mounting surface 10b of the lower plastic 10. Specifically, the explosion-proof fence 101 is located in the middle of the lower plastic 10.

[0047] In the embodiment, the lower plastic 10 is further provided with a liquid inlet hole 102 and two through holes 103. The liquid inlet hole 102 and the two through holes 103 all penetrate the first mounting surface 10a and the second mounting surface 10b of the lower plastic 10 and are arranged at intervals. Specifically, along the length direction (the X-axis direction shown in the figure) of the energy storage device 100, the liquid inlet hole 102 is located at the middle of the lower plastic 10 and at one side of the explosion-proof fence 101 and is arranged at an interval from the explosion-proof fence 101.

[0048] Along the length direction (the X-axis direction shown in the figure) of the energy storage device 100, the two through holes 103 are both located at the edge of the lower plastic 10 and are arranged at intervals from the liquid inlet hole 102 and the explosion-proof fence 101. Specifically, one through hole 103 is located at the side of the liquid inlet hole 102 away from the explosion-proof fence 101, and the other through hole 103 is located at the side of the explosion-proof fence 101 away from the liquid inlet hole 102.

[0049] Please refer to Figure 4 and Figure 6 , Figure 6 is Figure 3 the structure diagram of the cover plate 20 and the explosion-proof valve 30 in the end cover assembly 120 shown in

[0050] The cover plate 20 is mounted on the second mounting surface 10b of the lower plastic 10. In the embodiment, the cover plate 20 includes a first surface 20a and a second surface 20b, which are arranged at an interval along the thickness direction (the Z-axis direction shown in the figure) of the cover plate 20. The first surface 20a is the side of the cover plate 20 facing the lower plastic 10, and the second surface 20b is the side of the cover plate 20 away from the lower plastic 10.

[0051] The cover plate 20 is further provided with an explosion-proof hole 201, a liquid injection hole 202 and two assembly holes 203. The explosion-proof hole 201, the liquid injection hole 202 and the two assembly holes 203 all penetrate the first surface 20a and the second surface 20b of the cover plate 20 and are arranged at intervals. Specifically, the explosion-proof hole 201 and the liquid injection hole 202 are both located at the middle of the cover plate 20. The explosion-proof hole 201 can communicate with the inside of the energy storage device 100 through the explosion-proof fence 101. Along the length direction (the X-axis direction shown in the figure) of the cover plate 20, the liquid injection hole 202 is located at one side of the explosion-proof hole 201. The liquid injection hole 202 communicates with the liquid inlet hole 102 of the lower plastic 10. The electrolyte can be injected into the accommodation cavity of the shell 110 (as shown in Figure 1 ) through the liquid injection hole 202 of the cover plate 20 and the liquid inlet hole 102 of the lower plastic 10 in sequence, so as to realize the perfusion of the electrolyte of the energy storage device 100.

[0052] Along the length direction of the energy storage device 100 (the direction of the X axis shown in the figure), the two assembly holes 203 are located at the edges of the cover plate 20, and are respectively located at the opposite sides of the explosion-proof hole 201 and the liquid injection hole 202. Specifically, one assembly hole 203 is located at the side of the liquid injection hole 202 away from the explosion-proof hole 201, and the other assembly hole 203 is located at the side of the explosion-proof hole 201 away from the liquid injection hole 202. Each assembly hole 203 is in communication with a through hole 103 of the lower plastic 10, so as to facilitate the installation of a pole unit 40.

[0053] Please continue to refer to Figure 4 and Figure 6 . The explosion-proof valve 30 is installed in the explosion-proof hole 201 and is fixedly connected to the hole wall of the explosion-proof hole 201. For example, the explosion-proof valve 30 can be fixedly connected to the hole wall of the explosion-proof hole 201 by welding to be installed in the explosion-proof hole 201. It can be understood that since the explosion-proof hole 201 is in communication with the inside and outside of the energy storage device 100, when the air pressure inside the energy storage device 100 is too large, the explosion-proof valve 30 will be broken under the action of the air pressure, and the gas inside the energy storage device 100 can be sequentially discharged to the outside of the energy storage device 100 through the explosion-proof fence 101 of the lower plastic 10 and the explosion-proof hole 201 in time, avoiding the explosion of the energy storage device 100 and improving the use reliability of the energy storage device 100.

[0054] In this embodiment, the two pole units 40 can have the same or similar structure. One of the pole units is a positive pole unit and is electrically connected to the positive tab of the battery cell. The other pole unit 40 is a negative pole unit and is electrically connected to the negative tab of the battery cell. Hereinafter, the structure of one pole unit 40 will be described in detail.

[0055] Please continue to refer to Figure 4 , Figure 7 and Figure 8 , Figure 7 is Figure 3 the exploded structural schematic view of the pole unit 40 in the end cover assembly 120 shown in Figure 8 is Figure 7 the sectional structural schematic view of the upper plastic 41 of the pole unit 40 along the B-B section shown in

[0056] The pole unit 40 includes an upper plastic 41, a pole 42, a sealing element 43, and a compression ring 44. The upper plastic 41, the sealing element 43, and the compression ring 44 are all sleeved on the pole 42 and are all arranged around the pole 42. Among them, the upper plastic 41 is located between the cover plate 20 and the pole 42 to avoid the short circuit problem caused by the direct contact between the pole 42 and the cover plate 20.

[0057] Specifically, the upper plastic 41 is arranged in a mounting hole 203 of the cover plate 20. The upper plastic 41 is provided with a mounting hole 411 and a matching groove 412. The mounting hole 411 penetrates the upper plastic 41 along the thickness direction of the upper plastic 41, and is coaxial and communicated with the mounting hole 203 of the cover plate 20. The opening of the matching groove 412 is located on the surface of the upper plastic 41 away from the cover plate 20. The matching groove 412 is recessed from the surface of the upper plastic 41 away from the cover plate 20 towards the cover plate 20, and penetrates the hole wall of the mounting hole 411 and is communicated with the mounting hole 411.

[0058] The upper plastic 41 further includes a main body part 413 and an extension part 414 fixedly connected to the main body part 413. Specifically, the main body part 413 is provided with the matching groove 412 and the mounting hole 411. The opening of the matching groove 412 is located on the surface of the main body part 413 away from the cover plate 20. The extension part 414 is fixedly connected to one side of the main body part 413 towards the cover plate 20. The extension part 414 is arranged around the peripheral side of the mounting hole 411. Specifically, the extension part 414 is arranged in the mounting hole 203 of the cover plate 20.

[0059] Please refer to Figure 7 and Figure 9 , Figure 9 is Figure 7 the sectional structure schematic diagram of the pole 42 of the pole unit 40 shown in FIG. 4 along C-C.

[0060] The pole 42 is arranged in the mounting hole 411 of the upper plastic 41, the mounting hole 203 of the cover plate 20 and the through hole 103 of the lower plastic 10. The pole 42 includes a flange part 42c, a matching part 42b and a fixed part 42a, and the matching part 42b and the fixed part 42a are located on one side of the thickness direction of the flange part 42c. Specifically, the flange part 42c of the pole 42 is located in the matching groove 412 of the upper plastic 41. In other words, the flange part 42c of the upper plastic 41 is between the cover plate 20. The matching part 42b is fixedly connected to the flange part 42c, and is arranged in the mounting hole 411 of the upper plastic 41, the mounting hole 203 of the cover plate 20 and the through hole 103 of the lower plastic 10. In other words, the extension part 414 of the upper plastic 41 is connected between the peripheral side surface of the matching part 42b of the pole 42 and the hole wall surface of the mounting hole 203. The peripheral side surface of the flange part 42c is protruded relative to the peripheral side surface of the matching part 42b. The fixed part 42a is fixedly connected to one side of the matching part 42b away from the flange part 42c. The peripheral side surface of the matching part 42b is protruded relative to the peripheral side surface of the fixed part 42a. In the embodiment, the fixed part 42a is used for welding and fixing the compression ring 44. The fixed part 42a includes a welding surface 422 away from the first surface 20a of the cover plate 20. The welding surface 422 can be used for laser welding with the compression ring 44 and the adapter sheet of the energy storage device 100.

[0061] The pole post 42 is further provided with a groove 421. An opening of the groove 421 is located on a surface of the pole post 42 away from the first surface 20a of the cover plate 20. The groove 421 penetrates through a circumferential surface of the pole post 42 and is arranged around the pole post 42. Specifically, the fixing portion 42a is provided with the groove 421, and an opening of the groove 421 is located on a surface of the fixing portion 42a away from the matching portion 42b. The groove 421 is recessed from the surface of the fixing portion 42a away from the matching portion 42b to the direction of the matching portion 42b, penetrates through the circumferential surface of the fixing portion 42a, and is arranged around the fixing portion 42a.

[0062] In the embodiment, the groove wall surface of the groove 421 includes a first groove wall surface 421a and a second groove wall surface 421b. Specifically, the first groove wall surface 421a is located on one side of the circumferential surface of the fixing portion 42a of the pole post 42 away from the circumferential surface of the matching portion 42b. The second groove wall surface 421b is arranged opposite to the opening of the groove 421 and is connected between the circumferential surface of the pole post 42 and the first groove wall surface 421a. Specifically, the second groove wall surface 421b is connected between the circumferential surface of the fixing portion 42a and the first groove wall surface 421a. Wherein, from the circumferential surface of the fixing portion 42a of the pole post 42 to the direction of the first groove wall surface 421a, the distance between the second groove wall surface 421b and the welding surface 422 gradually decreases. That is, the second groove wall surface 421b is an inclined surface.

[0063] In the embodiment, the pole post 42 is a negative pole post. In some other embodiments, the pole post 42 can also be a positive pole post, and the embodiments of the present application do not make strict limitation thereon. In the embodiment, the pole post 42 further includes a first metal portion 423 and a second metal portion 424. Along the thickness direction of the end cover assembly 120, the first metal portion 423 is located on one side of the second metal portion 424 and covers the surface of the second metal portion 424 facing the first metal portion 423. Wherein, the outer circumferential surface of the first metal portion 423 is the outer circumferential surface of the pole post 42, and the first metal portion 423 is provided with the groove 421. Specifically, the first metal portion 423 is made of copper metal material, and the second metal portion 424 is made of aluminum metal material.

[0064] In the embodiment, the first metal portion 423 and the second metal portion 424 are integrally formed. Specifically, the first metal portion 423 and the second metal portion 424 are integrally formed through a stamping process. In the manufacturing process of the pole post 42, a solid-liquid composite manufacturing process is adopted to pour molten aluminum liquid onto a copper plate and roll to combine into a copper-aluminum composite plate. At this time, the copper-aluminum combination interface is planar, and the internal force is intermolecular, which is tightly occluded. Finally, the copper-aluminum composite plate is stamped to form the pole post. Under this setting, the processing technology of the pole post 42 is simple, the production efficiency is high, and the manufacturing cost of the pole post 42 can be effectively reduced.

[0065] Please refer to Figures 10 to 12 , Figure 10 is Figure 7A structural schematic view of the pressure ring 44 in the pole post unit 40 shown, Figure 11 is Figure 10 A structural schematic view of the pressure ring 44 shown at another angle, Figure 12 is Figure 10 A sectional structural schematic view of the pressure ring 44 along D-D.

[0066] In this embodiment, the pressure ring 44 is located on the side of the first surface 20a of the cover plate 20 away from the second surface 20b. Specifically, the pressure ring 44 is installed on the side of the lower plastic 10 away from the cover plate 20. It can be understood that by installing the pressure ring 44 on the side of the lower plastic 10 away from the cover plate 20, the short circuit problem caused by the direct contact between the pressure ring 44 and the cover plate 20 can be avoided, thereby helping to improve the safety performance of the end cover assembly 120.

[0067] Specifically, the pressure ring 44 includes a pressure ring body 44a and a protruding portion 44b, and the protruding portion 44b is fixedly connected to the pressure ring body 44a. The pressure ring body 44a includes a third surface 441 and a fourth surface 442. The third surface 441 faces the cover plate 20. The fourth surface 442 is arranged opposite to the third surface 441 along the thickness direction of the pressure ring body 44a. The pressure ring body 44a is provided with a matching hole 448. The matching hole 448 penetrates the third surface 441 and the fourth surface 442 of the pressure ring body 44a and communicates with one assembly hole 203 of the cover plate 20, so as to facilitate the installation of the pole post 42. For example, the matching hole 448 is a circular hole. The protruding portion 44b is fixedly connected to the hole wall surface of the matching hole 448 and is arranged around the center of the matching hole 448. The protruding portion 44b is located on the side of the third surface 441 away from the fourth surface 442.

[0068] When the pressure ring 44 is assembled with the pole post 42, the pole post 42 also penetrates the matching hole 448 of the pressure ring body 44a. Specifically, the fixed portion 42a of the pole post 42 penetrates the matching hole 448 of the pressure ring body 44a. The protruding portion 44b is installed in the groove 421 and is welded to the groove wall surface of the groove 421 and is arranged around the pole post 42.

[0069] In this embodiment, the protruding portion 44b comprises a first side surface 445, a second side surface 446 and a fifth surface 447. Specifically, the first side surface 445 faces and is welded to the first slot wall surface 421a, the second side surface 446 is connected between the hole wall surface of the matching hole 448 and the first side surface 445 and faces the second slot wall surface 421b and is welded to the second slot wall surface 421b. The fifth surface 447 is the surface of the protruding portion 44b facing away from the cover plate 20. The distance between the second side surface 446 and the fifth surface 447 gradually decreases from the hole wall surface of the matching hole 448 to the first side surface 445. That is, the second side surface 446 of the protruding portion 44b is a bevel. With this arrangement, the structural features of the two sides of the thickness direction of the compression ring 44 are obviously different, so that the compression ring 44 can be effectively prevented from being installed in reverse during assembly, and the compression ring 44 and the pole piece 42 can be quickly assembled, thereby improving the production efficiency of the end cover assembly 120.

[0070] It should be appreciated that when the compression ring 44 and the pole piece 42 are laser welded, the laser is easy to enter the assembly gap between the pole piece 42 and the compression ring 44. In this embodiment, by providing the protruding portion 44b on the compression ring 44 and the groove 421 on the pole piece 42, and locating the protruding portion 44b in the groove 421 of the pole piece 42, on the one hand, the laser leakage path in the assembly gap between the pole piece 42 and the compression ring 44 can be extended, and the laser burn of the upper plastic 41 can be avoided, thereby avoiding the welding burst point problem caused by the heat melting burn of the upper plastic 41, and further helping to improve the welding yield of the compression ring 44 and the pole piece 42, and reducing the scrap rate of the energy storage device 100 process. On the other hand, the area of the matching surface of the compression ring 44 and the pole piece 42 can be increased, and the assembly reliability between the pole piece 42 and the compression ring 44 can be improved. At the same time, during the assembly of the pole piece 42 and the compression ring 44, since the second slot wall surface 421b of the pole piece 42 is a bevel, the second slot wall surface 421b of the pole piece 42 can guide the assembly of the compression ring 44, facilitating the quick assembly and positioning of the compression ring 44 and the pole piece 42, thereby helping to improve the production and assembly efficiency of the end cover assembly 120.

[0071] On this basis, by locating the protruding portion 44b on the side of the third surface 441 facing the fourth surface 442, the surface of the compression ring 44 facing the cover plate 20 can be distributed in a stepped manner, thereby further extending the laser leakage path in the assembly gap between the pole piece 42 and the compression ring 44, avoiding the laser burn of the upper plastic 41, thereby further preventing the welding burst point problem caused by the heat melting burn of the upper plastic 41, improving the welding yield of the compression ring 44 and the pole piece 42, and further helping to reduce the scrap rate of the energy storage device 100 process.

[0072] Please continue to refer to Figures 10 to 12The compression ring body 44a is further provided with a protruding rib 443. The protruding rib 443 is arranged around the matching hole 448 and abuts against the surface of the matching part 42b of the pole 42 towards the fixing part 42a. Exemplarily, the protruding rib 443 is in the shape of a ring. After the end cover assembly 120 is assembled, the protruding rib 443 is located on the side of the extending part 414 of the upper plastic 41 towards the pole 42. In this arrangement, the protruding rib 443 can block the laser light entering the assembly gap between the compression ring 44 and the pole 42, thereby further preventing the laser light from burning the upper plastic 41, solving the problem of welding burst caused by the burning of the upper plastic 41 due to heat melting, improving the welding yield of the compression ring 44 and the pole 42, and reducing the scrap rate of the energy storage device 100.

[0073] The protruding rib 443 is provided with a notch 443a penetrating the protruding rib 443 along the width direction of the protruding rib 443. The width direction of the protruding rib 443 is parallel to the proceeding direction of the matching hole 448. In this arrangement, the notch 443a can prevent the matching part 42b of the pole 42 and the compression ring body 44a from being pressed too tightly, prevent the formation of a false sealing state between the pole 42 and the compression ring 44, and avoid the identification of poor welding between the pole 42 and the compression ring 44, thereby helping to detect products with abnormal sealing states, preventing unqualified products from flowing out, and further helping to improve the production quality of the products.

[0074] In this embodiment, the notch 443a has a plurality of notches. The plurality of notches 443a are arranged at intervals. In this embodiment, the number of notches 443a is less than or equal to 8, so as to avoid the abnormal sealing between the pole 42 and the compression ring 44 caused by too many notches 443a. Exemplarily, the number of notches 443a is 4.

[0075] The compression ring body 44a is further provided with a positioning groove 444. The opening of the positioning groove 444 is located on the fourth surface 442. The positioning groove 444 is recessed from the fourth surface 442 towards the third surface 441. The positioning groove 444 is arranged around the protruding part 44b and is arranged at intervals with the protruding part 44b. Along the thickness direction of the compression ring body 44a, the positioning groove 444 is arranged corresponding to the protruding rib 443. The positioning groove 444 can engage with the adapter tab with a protruding structure to provide quick positioning for the adapter tab and improve the assembly precision between the adapter tab and the compression ring 44 and the pole 42. In this embodiment, the positioning groove 444 can be formed by stamping the adapter tab 50 from the fourth surface 442 towards the third surface 441, and the protruding rib 443 is formed on the third surface 441, that is, the protruding rib 443 and the positioning groove 444 are formed at the same time in one stamping process, thereby simplifying the manufacturing process of the compression ring 44 and reducing the production cost of the compression ring 44.

[0076] In addition, along the thickness direction of the end cover assembly 120, the fourth surface 442 and the fifth surface 447 of the compression ring 44 are both located on the side of the welding surface 422 of the pole post 42 facing the first surface 20a. It should be understood that the welding surface 422 of the pole post 42 is usually also welded with the adapter tab of the energy storage device 100 to realize the electrical connection between the pole post 42 and the battery cell of the energy storage device 100. By locating the fourth surface 442 and the fifth surface 447 on the side of the welding surface 422 facing the first surface 20a, it can be prevented that the fourth surface 442 and the fifth surface 447 of the compression ring 44 are higher than the welding surface 422, so as to avoid the interference of the compression ring 44 to the welding between the adapter tab and the pole post 42, and thus the smooth welding between the pole post 42 and the adapter tab can be ensured.

[0077] Please refer again to Figure 4 . The sealing member 43 is sleeved on the extension portion 414 of the upper plastic 41 and clamped between the compression ring body 44a of the compression ring 44 and the cover plate 20. It can be understood that the sealing member 43 not only can keep the assembly stability between the compression ring 44 and the cover plate 20, but also can avoid the direct contact and conduction between the compression ring body 44a and the cover plate 20, so as to realize the insulation between the compression ring 44 and the cover plate 20.

[0078] In the assembly process of the end cover assembly 120, the pole post 42 is first arranged in one assembly hole 203 of the cover plate 20, and then the upper plastic 41 is sleeved on the pole post 42. At this time, the flange portion 42c of the pole post 42 is installed in the matching groove 412 of the upper plastic 41, and the matching portion 42b of the pole post 42 is arranged in the mounting hole 411 of the upper plastic 41. Then, the cover plate 20 is sleeved on the extension portion 414 of the upper plastic 41. Next, the lower plastic 10 is installed on the first surface 20a of the cover plate 20. At this time, the matching portion 42b of the pole post 42 and the extension portion 414 of the upper plastic 41 are both arranged in one through hole 103 of the lower plastic 10 and are both in clearance fit with the through hole 103. After that, the sealing member 43 is installed in one through hole 103 of the lower plastic 10 and is sleeved on the extension portion 414 of the upper plastic 41. Finally, the compression ring 44 is sleeved on the pole post 42. At this time, the protruding portion 44b of the compression ring 44 is installed in the groove 421 of the pole post 42, and the protruding rib 443 of the compression ring 44 abuts against the surface of the matching portion 42b of the pole post 42 facing the fixed portion 42a. At the same time, the upper plastic 41 is located on the side of the third surface 441 of the compression ring 44 away from the fourth surface 442. In addition, the sealing member 43 is clamped between the cover plate 20 and the compression ring body 44a of the compression ring 44 to realize the sealing between the compression ring 44 and the cover plate 20.

[0079] Please refer to Figure 13 , Figure 13 is Figure 4 the structural schematic view of the end cover assembly 120 after the welding is completed.

[0080] After the end cover assembly 120 is assembled, the pole 42 and the compression ring 44 are laser welded. During the laser welding of the pole 42 and the compression ring 44, the edge of the protruding portion 44b of the compression ring 44 facing the groove wall surface of the groove 421 of the pole 42 and the edge of the fixed portion 42a of the pole 42 facing the protruding portion 44b are melted together by laser energy injection, and then cooled to form a fusion portion 45. It can also be understood that the end cover assembly 120 further comprises the fusion portion 45, and the fusion portion 45 is formed by fusion of the portion of the protruding portion 44b close to the pole 42 and the portion of the pole 42 close to the protruding portion 44b. Specifically, the fusion portion 45 is located on the side of the third surface 441 facing the fourth surface 442, and on the side of the protruding portion 44b facing the groove wall surface of the groove 421, and is connected to the fixed portion 42a of the pole 42.

[0081] It can be understood that, since the upper plastic 41 is located on the side of the third surface 441 of the compression ring 44 away from the fourth surface 442, the distance between the upper plastic 41 and the fusion portion 45 welded between the compression ring 44 and the pole 42 is long, which can reduce the laser heat received by the upper plastic 41 during welding, thereby avoiding the upper plastic 41 from being burned and melted, preventing welding spatter, and further helping to improve the welding yield of the compression ring 44 and the pole 42, and reducing the scrap rate of the energy storage device 100.

[0082] Please refer to Figures 14 to 16 , Figure 14 is Figure 2 the cross-sectional structure schematic view of the end cover assembly 120 shown in FIG. 2 along A-A in the second embodiment, Figure 15 is Figure 14 the cross-sectional structure schematic view of the pole 42 in the end cover assembly 120 shown in FIG. 2, Figure 16 is Figure 14 the cross-sectional structure schematic view of the compression ring 44 in the end cover assembly 120 shown in FIG. 2.

[0083] The end cover assembly 120 shown in the embodiment is different from the end cover assembly 120 shown in the first embodiment in that, from the direction of the peripheral surface of the pole 42 to the first groove wall surface 421a, the distance between the second groove wall surface 421b and the welding surface 422 is unchanged. From the direction of the hole wall surface of the mating hole 448 to the first side surface 445, the distance between the second side surface 446 and the fifth surface 447 is unchanged.

[0084] In this arrangement, the assembly gap between the pole 42 and the compression ring 44 can be extended to avoid laser leakage, so as to avoid the laser burn of the upper plastic 41, and thus to avoid the welding burst problem caused by the laser burn of the upper plastic 41, and to improve the welding yield of the compression ring 44 and the pole 42, and to reduce the scrap rate of the energy storage device 100. At the same time, the area of the fitting surface of the compression ring 44 and the pole 42 can be increased, and the assembly reliability of the pole 42 and the compression ring 44 can be improved.

[0085] Please refer to Figure 17 and Figure 18 , Figure 17 is Figure 2 the cross-sectional structure of the end cover assembly 120 shown in FIG. 1 along A-A in the third embodiment, Figure 18 is Figure 17 the cross-sectional structure of the pole 42 in the end cover assembly 120 shown in FIG. 1.

[0086] The end cover assembly 120 shown in the embodiment is different from the end cover assembly 120 shown in the first embodiment in that the pole 42 further comprises a chamfered portion 42d. The chamfered portion 42d is located on the side of the fitting portion 42b away from the fixed portion 42a, and is connected between the flange portion 42c and the fitting portion 42b. The diameter of the chamfered portion 42d gradually decreases from the flange portion 42c to the fitting portion 42b. The peripheral side surface of the first metal portion 423 comprises the peripheral side surface of the chamfered portion 42d.

[0087] It should be understood that in the existing pole 42, the connection between the part of the first metal portion 423 forming the flange portion 42c and the part of the first metal portion 423 forming the fitting portion 42b is the weakest position in the pole 42. In the mass production process, the first metal portion 423 is prone to breakage at this weak position, resulting in separation of the first metal portion 423 and the second metal portion 424. In the embodiment, by providing the chamfered portion 42d between the flange portion 42c and the fitting portion 42b, the thickness of the first metal portion 423 at the weak position of the pole 42 can be increased, so as to prevent the first metal portion 423 from breaking in the mass production process of the pole 42, and thus to improve the production yield of the pole 42.

[0088] Please refer to Figure 17 , Figure 19 and Figure 20 , Figure 19 is Figure 17 the structure of the upper plastic 41 in the end cover assembly 120 shown in FIG. 1, Figure 20 is Figure 19 the cross-sectional structure of the upper plastic 41 shown in FIG. 1 along E-E.

[0089] In the embodiment, the inner circumferential surface of the upper plastic 41 comprises a first portion 41a, a second portion 41b, a third portion 41c and a fourth portion 41d. Specifically, the first portion 41a is arranged towards and around the circumferential surface of the fitting portion 42b. The second portion 41b is connected to one side of the first portion 41a along the thickness direction of the end cover assembly 120, arranged towards and around the circumferential surface of the chamfer portion 42d. The third portion 41c is connected to one side of the second portion 41b away from the first portion 41a, arranged towards the surface of the flange portion 42c facing the cover plate 20 and around the chamfer portion 42d. The fourth portion 41d is connected to one side of the third portion 41c away from the second portion 41b, arranged towards the circumferential surface of the flange portion 42c and around the flange portion 42c. The diameter of the second portion 41b gradually decreases from the third portion 41c to the first portion 41a. With the above arrangement, the inner circumferential surface of the upper plastic 41 can be adapted to the circumferential surface of the pole 42, thereby enhancing the assembly reliability between the upper plastic 41 and the pole 42.

[0090] The application further provides a power consuming device, which comprises the above-mentioned energy storage device 100, and the energy storage device 100 supplies power to the power consuming device. The power consuming device can be a new energy vehicle, a power storage station, a server or other devices requiring power supply.

[0091] The above description is only a specific embodiment of the application, but the protection scope of the application is not limited thereto, and any person skilled in the art can easily think of changes or replacements within the technical scope disclosed in the application, which should be covered in the protection scope of the application. In the case of no conflict, the embodiments of the application and the features in the embodiments can be combined with each other. Therefore, the protection scope of the application should be subject to the protection scope of the claims.

Claims

1. An end cap assembly for use in an energy storage device, characterized by, The end cover assembly comprises a cover plate, a pole, an upper plastic, a compression ring and a welding part, the cover plate comprises a first surface and a second surface, the first surface and the second surface are oppositely arranged along the thickness direction of the cover plate, the cover plate is provided with an assembly hole penetrating through the first surface and the second surface; The compression ring is located on the side of the first surface away from the second surface, the compression ring comprises a compression ring body and a protruding part, the compression ring body comprises a third surface and a fourth surface, the third surface faces the cover plate, the fourth surface is oppositely arranged with the third surface along the thickness direction of the compression ring body, the compression ring body is provided with a matching hole penetrating through the third surface and the fourth surface and communicating with the assembly hole, and the protruding part is arranged on the hole wall surface of the matching hole and surrounds the center of the matching hole, wherein the protruding part is located on the side of the third surface facing the fourth surface; The pole is arranged in the assembly hole and the matching hole, the pole is provided with a groove, the opening of the groove is located on the surface of the pole away from the first surface, the groove penetrates through the surface of the pole facing the hole wall surface of the matching hole and surrounds the pole, wherein the protruding part is mounted in the groove and welded on the groove wall surface and surrounds the pole; The welding part is located on the side of the third surface facing the fourth surface and the side of the protruding part facing the groove wall surface of the groove and is connected to the pole; The upper plastic is located on the side of the third surface away from the fourth surface and is arranged in the assembly hole, the upper plastic surrounds the pole and is located between the pole and the cover plate.

2. The end cap assembly of claim 1, wherein, The pole comprises a welding surface, the welding surface is located on the side of the first surface away from the second surface, and the welding surface is used for welding with the adapter sheet of the energy storage device; The groove wall surface comprises a first groove wall surface and a second groove wall surface, the first groove wall surface is located on the side of the circumferential surface of the pole away from the hole wall surface of the matching hole, the second groove wall surface is oppositely arranged with the opening of the groove and is connected between the circumferential surface of the pole and the first groove wall surface, and the distance between the second groove wall surface and the welding surface gradually decreases from the circumferential surface of the pole to the first groove wall surface; The protruding part comprises a fifth surface, a first side surface and a second side surface connected in sequence, the first side surface faces the first groove wall surface and is welded on the first groove wall surface, the second side surface is connected between the hole wall surface of the matching hole and the first side surface and faces the second groove wall surface and is welded on the second groove wall surface, and the fifth surface is the surface of the protruding part away from the cover plate, and the distance between the second side surface and the fifth surface gradually decreases from the hole wall surface of the matching hole to the first side surface.

3. The end cap assembly of claim 2, wherein, The distance between the second groove wall surface and the welding surface is constant from the circumferential surface of the pole to the first groove wall surface. The distance between the second side and the fifth surface is constant from the direction of the hole wall of the fitting hole facing the first side.

4. An end cap assembly according to claim 2 or 3, wherein, The pole includes a fixed part and a fitting part connected with each other, the fitting part is arranged in the assembly hole, the fixed part is located on the side of the first surface away from the second surface, is fixedly connected with the fitting part, and is arranged in the fitting hole, the fixed part includes the welding surface, the fixed part is provided with the groove, the opening of the groove is located on the welding surface, the groove penetrates through the circumferential surface of the fixed part, and surrounds the fixed part, wherein the circumferential surface of the fitting part protrudes relative to the circumferential surface of the fixed part.

5. The end cap assembly of claim 4, wherein, The third surface is provided with a protruding rib, the protruding rib is arranged around the fitting hole, and abuts against the surface of the fitting part facing the fixed part.

6. The end cap assembly of claim 5, wherein, The protruding rib is provided with a notch, and the notch penetrates through the protruding rib along the width direction of the protruding rib.

7. The end cap assembly of claim 5, wherein, The compression ring body is further provided with a positioning groove, the opening of the positioning groove is located on the fourth surface, the positioning groove is arranged around the protruding part and is spaced apart from the protruding part, and the positioning groove is arranged corresponding to the protruding rib along the thickness direction of the compression ring body.

8. The end cap assembly of claim 4, wherein, The pole further includes a flange part and a chamfer part, the flange part and the chamfer part are located on the side of the fitting part away from the fixed part, the chamfer part is connected between the flange part and the fitting part, and the diameter of the chamfer part gradually decreases from the flange part to the fitting part. The inner circumferential surface of the upper plastic includes a first part, a second part, a third part and a fourth part, the first part faces the circumferential surface of the fitting part and surrounds the fitting part, the second part is connected to one side of the first part and faces the circumferential surface of the chamfer part and surrounds the chamfer part along the thickness direction of the end cover assembly, the third part is connected to one side of the second part away from the first part and faces the surface of the flange part facing the cover plate and surrounds the chamfer part, and the fourth part is connected to one side of the third part away from the second part and faces the circumferential surface of the flange part and surrounds the flange part, wherein the diameter of the second part gradually decreases from the third part to the first part.

9. The end cap assembly of claim 8, wherein, The pole includes a first metal part and a second metal part, the first metal part is located on one side of the second metal part and covers the surface of the second metal part facing the first metal part along the thickness direction of the end cover assembly, the first metal part is provided with the groove, and the circumferential surface of the first metal part includes the circumferential surface of the chamfer part.

10. The end cap assembly of claim 2 or 3, wherein, The fourth surface and the fifth surface are located on the side of the welding surface facing the first surface along the thickness direction of the end cover assembly.

11. An energy storage device, characterized by, The end cover assembly as claimed in any one of claims 1 to 10 is mounted in the housing and seals the opening of the housing.

12. An electrical device, characterized by The energy storage device as claimed in claim 11 is used to supply power to the electric device.

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