Secondary battery cell

Abstract

The utility model relates to a secondary battery monomer, which comprises a shell, an outer peripheral wall surrounded by a cavity, an end wall at least partially sealing the front end of the outer peripheral wall, an opening formed by penetrating through the rear end of the outer peripheral wall, and a mounting hole formed by penetrating through the end wall, the section of the opening is consistent with that of the cavity; the electrode assembly comprises a substrate with a first through hole formed in a penetrating manner and a pole fixed in the mounting hole; the top cover assembly is welded to the opening of the shell in a sealed mode. The front end and the rear end of the battery cell unit are electrically connected with the electrode assembly and the top cover assembly respectively; the battery cell unit is fixedly connected with the electrode assembly and the top cover assembly and is arranged in the cavity from one end of the opening, the edge of a substrate of the electrode assembly is limited on the inner side of the end wall of the periphery of the mounting hole and is welded with the end wall into a whole, and the top cover assembly is welded on the opening and seals the opening. According to the invention, the assembly process is simplified, and the efficiency is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of batteries, and in particular to a secondary battery cell. BACKGROUND

[0002] Secondary battery refers to a battery that can be repeatedly charged and discharged multiple times. At present, secondary batteries are widely used as automobile power devices and energy storage devices, which has brought significant changes to the energy structure of society and greatly reduced carbon emissions of automobiles. A plurality of secondary battery cells are combined into a battery pack to store and release electrical energy to an electrical device. Secondary battery cells include various types, such as cylindrical, square, blade-shaped, and various structures. The existing square battery generally includes a battery shell with two open ends and other closed surfaces, an electrode material mounted in the battery shell, and a battery top cover closing the two open ends of the battery shell. During assembly, the electrode material is first mounted in the space of the battery shell, and then two battery top covers are used to close the two open ends of the battery shell. Before closing the two open ends of the battery shell, the electrode material needs to be electrically connected to the pole column on the battery top cover. In this process, the electrode material is mounted in the space of the battery shell and then welded to the battery top cover, which has the problems of limited operation space and complicated process. It is necessary to optimize the product structure and develop a more simplified and easy-to-operate assembly method.

[0003] At the same time, the battery top cover of the traditional secondary battery is usually adhered to the outside of the battery shell from the open end of the battery shell and welded and sealed, which limits the battery shell with two open ends from being welded and fixed with the electrode before assembly, and only a certain welding space is left to weld the adapter piece and then buckle it to the outside of the battery shell for sealed welding. At the same time, part of the cylindrical pole column will also rotate, and the traditional method is to make part of the cylindrical surface into a straight surface shape to prevent rotation, but this will affect the current carrying capacity and strength of the product. CONTENT OF THE INVENTION

[0004] Therefore, it is necessary to provide a secondary battery cell that is easy to assemble and stable and reliable.

[0005] To solve the above technical problems, the application provides a secondary battery cell, which comprises a shell, an electrode assembly, a top cover assembly and an electric core unit.

[0006] Preferably, the electric core unit is fixed through a support, and the electrode assembly and the top cover assembly are respectively electrically connected to the electric core unit through adapter plates and then fixed to the support.

[0007] Preferably, the inner surface of the end wall located at the edge of the mounting hole is recessed to form an inner groove and a convex edge, the edge of the substrate of the electrode assembly is clamped into the inner groove and located inside the convex edge, and the edge of the substrate and the convex edge are welded together.

[0008] Preferably, the substrate of the electrode assembly comprises a base part, a first through hole formed through the base part, a first step part and a second step part arranged in the radial direction outward from the outer surface of the base part in sequence, the second step part is fitted into the inner groove of the end wall and abuts against the inside of the convex edge, the first step part is in the same horizontal plane as the outer surface of the end wall, the outer edge of the first step part abuts against the inner edge of the convex edge, and the abutting part of the first step part and the convex edge is welded and sealed.

[0009] Preferably, the convex edge and the outer edge of the first step part are provided with a groove structure, the groove structure is filled with solder, and the solder is melted to realize sealing and welding.

[0010] Preferably, the surface of the base part as the first step part or the outer surface of the base part is higher than the surface of the first step part.

[0011] Preferably, the base portion is provided with an inner ring groove and an outer ring groove on the inner and outer sides of the periphery of the first through hole respectively, the inner diameter of the inner ring groove is larger than the inner diameter of the outer ring groove, the electrode assembly further comprises an isolation pad limited in the outer ring groove and an insulating member limited in the inner ring groove, the pole post comprises a post body, a lower limiting portion protruding radially outward from the lower end of the post body and limited below the insulating member and the inner ring groove, an upper limiting portion outwardly folded from the upper end of the post body and pressed on the isolation pad and above the outer ring groove, and a sealing ring pressed between the lower limiting portion and the surface of the inner ring groove.

[0012] Preferably, the insulating member comprises a connecting body extending vertically, an isolation portion extending radially inward from the upper end of the connecting body, a third through hole formed through the isolation portion, and an insulating main body extending radially outward from the lower end of the connecting body, the connecting body and the isolation portion are limited in the inner ring groove, the isolation portion and the connecting body isolate the substrate and the pole post, the insulating main body covers the lower surface of the substrate, and the lower limiting portion is limited in the connecting body.

[0013] Preferably, the isolation pad comprises a horizontal pad ring supported on the surface of the outer ring groove, a second through hole formed through the horizontal pad ring, an outer edge upward extending portion extending upward from the outer edge of the horizontal pad ring, and an inner edge downward extending portion extending downward from the inner edge of the horizontal pad ring, the upper limiting portion of the pole post is pressed above the horizontal pad ring and is limited within the range of the outer edge upward extending portion, the inner edge downward extending portion extends along the hole wall of the first through hole, and the sealing ring comprises a first sealing ring body pressed between the inner ring groove and the lower limiting portion, and a second sealing ring body pressed between the lower limiting portion and the inner edge downward extending portion.

[0014] Preferably, the top cover assembly comprises a substrate and a pole post assembled on the substrate, an edge buckle groove is formed on the inner side of the outer edge of the substrate, the edge buckle groove is buckled on the peripheral wall of the shell and is welded and fixed together.

[0015] Compared with the prior art, the secondary battery cell of the application only needs to open a mounting hole on the closed end wall at one end of the shell, and the cell unit, the electrode assembly, and the top cover assembly are first electrically connected, then inserted and assembled from the opening at one end of the shell, and finally the electrode assembly and the top cover assembly are welded to the mounting hole and the opening, which simplifies the difficulty of assembly and improves the processing efficiency.

[0016] The main point is that the electrode assembly is attached from the inside to the outside of the end wall, and the laser welding is irradiated from the outside, which simplifies the assembly process and takes into account the feasibility of laser welding. Compared with the prior art, both top cover assemblies need to be installed and welded from the outside, making the welding of the adapter piece more simple and feasible. BRIEF DESCRIPTION OF DRAWINGS

[0017] The accompanying drawings, which are included to provide a further understanding of the application and are incorporated in and constitute a part of this application, illustrate embodiments of the application and serve to explain the principles of the application. In the drawings:

[0018] Figure 1 is a perspective assembly view of a secondary battery cell of the present application;

[0019] Figure 2 is another perspective assembly view of a secondary battery cell of the present application;

[0020] Figure 3 is another perspective assembly view of a secondary battery cell of the present application;

[0021] Figure 4 is an exploded perspective view of a secondary battery cell of the present application;

[0022] Figure 5 is another exploded perspective view of a secondary battery cell of the present application;

[0023] Figure 6 is a sectional view of a secondary battery cell of the present application along the A-A line shown in the drawing; Figure 1

[0024] Figure 7 is an enlarged view of the dotted circle A shown in the drawing; Figure 6

[0025] Figures 8 to 16 is an embodiment of an electrode assembly and / or a top cover assembly;

[0026] Figure 8 is a perspective assembly view of an electrode assembly of the present application;

[0027] Figure 9 is an exploded perspective view of an electrode assembly of the present application;

[0028] Figure 10 is a sectional perspective view of an electrode assembly of the present application;

[0029] Figure 11 is another sectional perspective view of an electrode assembly of the present application;

[0030] Figure 12 is a front sectional view of an electrode assembly of the present application; ​​

[0031] Figure 13 For Figure 6 partial enlarged view of the dashed circle B shown in the figure;

[0032] Figure 14 is a perspective view of the top cover assembly of the present application;

[0033] Figure 15 is a perspective sectional view of the top cover assembly of the present application;

[0034] Figure 16 is a front sectional view of the top cover assembly of the present application;

[0035] Figure 17 is a front sectional view of the electrode assembly and / or the top cover assembly of the second embodiment of the present application;

[0036] Figure 18 is a front sectional view of the electrode assembly and / or the top cover assembly of the third embodiment of the present application;

[0037] Figure 19 is a front sectional view of another actual mode of the electrode assembly combined with the shell of the present application.

[0038] Explanation of Reference Signs

[0039] Shell-10; cavity-11; mounting hole-12; opening-13; end wall-14; convex edge-141; inner groove-142; outer peripheral wall-15; battery cell assembly-40; battery cell unit-41; adapter tab-42; bracket-43; rupture disc-50; electrode assembly-20; top cover assembly-30; base plate-21; base body-211; inner ring groove-212; outer ring groove-213; first step-214; second step-215; first through hole-216; inner ring groove protrusion-217; pole post-22; cylinder-221; lower limiting portion-222; upper limiting portion-223; anti-rotation notch-224; isolation pad-23; horizontal pad ring-231; inner edge lower extension-232; outer edge upper extension-233; second through hole-236; sealing ring-24; first sealing ring body-241; second sealing ring body-242; insulating member-25; connecting body-251; isolation portion-252; insulating main body-253; anti-rotation groove-254; anti-rotation protrusion-255; third through hole-256; edge buckle groove-218; steel pad-26; steel pad ring body-261; steel pad flange-262; welding area-S. DETAILED DESCRIPTION

[0040] In order to make the purpose, technical solutions and advantages of the present application clearer, the technical solutions of the present application will be described clearly and completely below in combination with the specific embodiments of the present application and corresponding drawings. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments.

[0041] The present application is related to Figure 1 The X direction is the front-rear direction, the Y direction is the lateral direction, and the Z direction is the up-down direction.

[0042] Please refer to Figure 1 , Figure 2 , Figures 4 to 6 As shown in the drawings, the secondary battery cell of the present application includes a shell 10 having a cavity 11 formed hollow in the front-rear direction and an opening 13 formed open at one end, an electrode assembly 20 loaded into the cavity 11 from the opening 13, a top cover assembly 30 closing the opening 13, and an electric core assembly 40.

[0043] The shell 10 includes a peripheral wall 15 formed by rotating the center axis in the X direction for one turn, the cavity 11 formed in the peripheral wall 15, an end wall 14 formed at the front end of the peripheral wall 15, a mounting hole 12 penetrating through the end wall 14, and the opening 13 formed open at the rear end. The shell 10 is one of a square structure, a circular structure, or a blade structure, and is made of any one of aluminum alloy, stainless steel, titanium alloy, and the like. In the square structure or the blade structure, an anti-explosion piece 50 is arranged on the side of the peripheral wall 15 with a smaller area. The anti-explosion piece 50 can be formed on the side of the peripheral wall 15 by etching, such as laser ablation. The anti-explosion piece 50 can also be formed by first stamping an anti-explosion notch, then opening an anti-explosion hole on the side of the peripheral wall 15, and finally welding the stamped anti-explosion piece 50 on the anti-explosion hole.

[0044] The shell of the secondary battery cell of the present application has multiple forming methods, and different manufacturing processes can be used for different metal materials. If the shell is made of aluminum alloy, it is preferable to use an aluminum alloy plate to form the shell by stamping and stretching. If the shell is made of stainless steel, the thickness of the shell will be greatly reduced, and it will be more difficult to use the stretching process. At this time, the thin steel plate can be bent and spliced into a predetermined shape and then welded and sealed. The titanium alloy material can also be formed by splicing and welding.

[0045] The electric core assembly 40 includes an electric core unit 41 in the middle, a conversion piece 42 connected to the electric core unit 41 at both front and rear ends, and a support 43 supporting the electric core unit 41 at both front and rear ends. The electrode assembly 20 is electrically connected to the front end of the electric core unit 41 through at least one conversion piece 42, and the top cover assembly 30 is electrically connected to the rear end of the electric core unit 41 through at least one conversion piece 42. The support 43 is used to fix the electric core unit 41 in the cavity 11 of the shell 10 to prevent the electric core unit 41 from shaking.

[0046] Please continue to refer to Figure 7As shown, the mounting hole 12 on the end wall 14 of the housing 10 is adapted to the electrode assembly 20. The end wall 14 is recessed on the inner side of the periphery of the mounting hole 12 to form an inner groove 142 surrounding the mounting hole 12, and a protruding edge 141 is formed on the outer side of the inner groove 142.

[0047] The electrode assembly 20 can be circular or racetrack-shaped, such as... Figure 1 , Figure 2 The diagram shows a runway-shaped structure. Figure 3 The diagram shows a circular structure; the electrode assembly 20 can also be square or other structures, but the electrode assembly 20 of this application can take many different shapes, although their internal structural principles are basically the same. The electrode assembly 20 of this application serves as the positive electrode of the secondary battery cell, and the top cover assembly 30 serves as the negative electrode of the secondary battery cell. However, the electrode assembly 20 and the top cover assembly 30 can also be used in reverse, serving as the negative and positive electrodes, respectively.

[0048] Please continue reading. Figures 8 to 12 As shown, for ease of description, the electrode assembly 20 of this application is referred to as... Figure 8 The L1 direction is defined as the radial direction, and the L2 direction is defined as vertically upward. The electrode assembly 20 of this application is assembled within the mounting hole 12 on the end wall 14 of the housing 10. The electrode assembly 20 includes a substrate 21 through which a first through hole 216 is formed, an electrode post 22 assembled within the first through hole 216, a sealing ring 24 pressed between the electrode post 22 and the substrate 21, an insulating pad 23 isolating the electrode post 22 and the substrate 21, and an insulating member 25.

[0049] Specifically, the substrate 21 includes a base portion 211, a first step portion 214 and a second step portion 215 arranged radially outward from the outer end face of the base portion 211, the first through hole 216 penetrating the base portion 211, an outer annular groove 213 formed on the outer side of the base portion 211 around the first through hole 216, and an inner annular groove 212 formed on the inner side of the base portion 211 around the first through hole 216. The inner diameter of the inner annular groove 212 is larger than the inner diameter of the outer annular groove 213. The inner surfaces of the first step portion 214 and the second step portion 215 are flush with the inner surface of the base portion 211, that is, the thickness of the first step portion 214 is greater than the thickness of the second step portion 215, and the inner diameter of the inner annular groove 212 is limited to the range of the outer diameter of the base portion 211.

[0050] The insulation 25 includes a connecting body 251 fitted on the radially inner wall surface of the inner ring groove 212, an isolation portion 252 extending radially inward from the top of the connecting body 251, an insulation main body 253 extending radially outward from the bottom of the connecting body 251 to cover the bottom surface of the substrate 21, and a third through hole 256 formed through the isolation portion 252. The third through hole 256 of the insulation 25 has a larger inner diameter than the first through hole 216 of the mounting hole substrate 21, and the isolation portion 252 is fitted on the top surface of the inner ring groove 212.

[0051] The pole 22 includes a pole body 221, a lower limiting portion 222 extending radially outward from the bottom of the pole body 221, and an upper limiting portion 223 folded radially outward from the top of the pole body 221. The middle portion of the pole body 221 protrudes outward beyond the surface of the upper limiting portion 223. The sealing ring 24 includes a first sealing ring body 241 and a second sealing ring body 242 protruding upward from the inner side of the first sealing ring body 241, and the radial thickness of the second sealing ring body 242 is smaller than the vertical thickness of the first sealing ring body 241.

[0052] The isolation pad 23 is arranged on the outer ring groove 213 around the first through hole 216 of the substrate 21 to support and isolate the upper limiting portion 223. Specifically, the isolation pad 23 includes a horizontal pad ring 231 fitted on the surface of the outer ring groove 213, an inner edge downward portion 232 extending downward from the inner side of the horizontal pad ring 231 to the inner wall surface of the first through hole 216, and an outer edge upward portion 233 extending upward along the edge of the outer ring groove 213 from the outer side of the horizontal pad ring 231.

[0053] Please refer to Figure 12As shown, when assembling the electrode assembly 20, the sealing ring 24 is first sleeved from top to bottom outside the column body 221 of the pole 22, and the first sealing ring body 241 of the sealing ring 24 is attached to the surface of the lower limiting portion 222, and the inner wall surface of the first sealing ring body 241 and the second sealing ring body 242 is attached to the outer surface of the column body 221; the insulating piece 25 is installed on the inner ring groove 212 inside the base plate 21, at this time, the connecting body 251 and the top surface of the isolation portion 252 are attached to the inner surface of the inner ring groove 212, but the isolation portion 252 only covers the inner surface of the inner ring groove 212 on the radial outer side, and the insulating main body 253 covers a certain area of the lower surface of the base plate 21; it should be noted that before assembly, the upper limiting portion 223 is not outwardly folded, but is flush with the outer surface of the column body 221 or does not exceed the outer surface of the column body 221 on the radial outer side, in this step, the unturned pole 22 is passed upward through the third through hole 256 and the first through hole 216, and the lower limiting portion 222 is received into the groove on the lower side of the isolation portion 252, that is, the lower limiting portion 222 and the insulating main body 253 at least partially overlap in the radial direction; the isolation pad 23 is sleeved from top to bottom outside the column body 221, specifically, the horizontal pad ring 231 of the isolation pad 23 is supported on the outer ring groove 213, and the inner edge lower extension portion 232 is attached to the outer surface of the column body 221 and extends downward into the first through hole 216 to isolate the column body 221 from the base plate 21; finally, the upper limiting portion 223 in the vertical state is outwardly folded by a tool to be pressed on the horizontal pad ring 231. After riveting is completed, the vertical thickness of the first sealing ring body 241 of the sealing ring 24 is thinned and expanded on the radial outer side, and finally, the outer edge of the first sealing ring body 241 will generate a certain extrusion force on the inner edge of the isolation portion 252 of the insulating piece 25 to achieve complete sealing, and the second sealing ring body 242 is extruded downward by the inner edge lower extension portion 232 of the isolation pad 23 to achieve sealing. The upper limiting portion 223 is at least partially wrapped by the outer edge upper extension portion 233.

[0054] It should be noted that the electrode assembly of the present application Figure 8 、 Figure 9 is a racetrack-shaped structure, Figure 10 、 Figure 11 is a cross-sectional perspective view of a circular structure, and Figure 12 the cross-sectional view is the same as that of the racetrack-shaped structure and the circular structure. Because the racetrack-shaped structure has a straight edge on the outer periphery, there is no need to worry about the rotation of the internal components, while the circular electrode assembly needs to ensure that the internal components do not rotate.

[0055] Please refer to Figure 10 、 Figure 11As shown, when the electrode assembly 20 is circular, an anti-rotation structure is required. Specifically, the base body part 211 of the base plate 21 is protruded towards the inner side of the radial direction to form an inner ring groove protrusion 217 in the inner ring groove 212. The connecting part 251 of the insulating part 25 is recessed inward to form an anti-rotation recess 254 and an anti-rotation protrusion 255 protruding to the lower side of the isolation part 252 at the position corresponding to the inner ring groove protrusion 217. The outer periphery of the lower limiting part 222 of the pole column 22 is formed with an anti-rotation notch 224 on the anti-rotation protrusion 255. After assembly, the base plate 21 is buckled into the anti-rotation recess 254 of the insulating part 25 to prevent rotation of the two, and the anti-rotation protrusion 255 of the insulating part 25 is clamped into the anti-rotation notch 224 outside the lower limiting part 222 of the pole column 22 to prevent rotation of the two. In this way, the electrode assembly 20 can effectively prevent the insulating part 25 and the pole column 22 from rotating relative to the base plate 21.

[0056] The electrode assembly 20 of the present application is provided with an anti-rotation notch 224 on the outer periphery of the lower limiting part 222 of the pole column 22 to cooperate with the insulating part 25 and the base plate 21, thereby achieving stability among the three. Compared with the conventional anti-rotation structure of the pole column 22 provided on the outer surface of the column body 221, the integrity of the column body 221 can be achieved, the transmission and carrying capacity of the column body 221 can be avoided from being damaged, and the processing difficulty and complexity of the pole column 22 can be effectively reduced, thereby reducing the manufacturing cost.

[0057] Please continue to refer to Figures 13 to 16 As shown, the top cover assembly 30 is basically similar in structure to the electrode assembly 20, except that the base plate 21 of the top cover assembly 30 is wider in area to cover the opening 13 at one end of the shell 10, and the inner side of the outer edge of the base plate 21 is provided with an edge buckle groove 218 to be fitted on the outer peripheral wall 15 of the shell 10 to achieve welding fixation. The base plate 21 has some differences in structure, specifically, the design of the second step part 215 is cancelled, and the rest of the structure is basically the same.

[0058] The adapter plate 42 is welded to the bottom surface of the pole column 22 of the electrode assembly 20 and the top cover assembly 30.

[0059] Please continue to refer to Figure 17 , Figure 18 As shown, the electrode assembly 20 and the top cover assembly 30 of the present application also include other embodiments. In order to ensure the gripping force of the upper limiting part 223 of the pole column 22, a steel pad 26 is clamped between the horizontal pad ring 231 of the isolation pad 23 and the upper limiting part 223. The steel pad 26 is a sheet structure (such as Figure 17As shown in the figure, the upper limiting part 223 is pressed against the horizontal gasket ring 231 through the steel gasket 26, so as to disperse the pressing force of the upper limiting part 223 against the horizontal gasket ring 231, and avoid damaging the isolation gasket 23. The steel gasket 26 further comprises a horizontal steel gasket ring body 261 and a steel gasket flange 262 which is folded upward from the outer edge of the steel gasket ring body 261 (as shown in the figure). The presence of the steel gasket flange 262 can limit the calendering range of the upper limiting part 223 when it is pressed and folded, so as to avoid damage to the outer edge upper extending part 233 caused by excessive pressing. Figure 18 As shown in the figure, the upper limiting part 223 is pressed against the horizontal gasket ring 231 through the steel gasket 26, so as to disperse the pressing force of the upper limiting part 223 against the horizontal gasket ring 231, and avoid damaging the isolation gasket 23. The steel gasket 26 further comprises a horizontal steel gasket ring body 261 and a steel gasket flange 262 which is folded upward from the outer edge of the steel gasket ring body 261 (as shown in the figure). The presence of the steel gasket flange 262 can limit the calendering range of the upper limiting part 223 when it is pressed and folded, so as to avoid damage to the outer edge upper extending part 233 caused by excessive pressing.

[0060] Please continue to refer to Figures 1 to 18 As shown in the figure, the following will be described in detail the assembling method of the secondary battery cell of the present application:

[0061] S10: The different adapter plates 42 are respectively welded and fixed to the pole 22 of the electrode assembly 20 and the top cover assembly 30; at the same time, the battery cell unit 41 is fixed to the bracket 43;

[0062] In this step, the adapter plate 42 is attached to the lower surface of the pole body 221 of the pole 22 and is welded and fixed together on one side of the adapter plate 42.

[0063] S20: The adapter plate 42 connected to the electrode assembly 20 and the top cover assembly 30 is electrically connected to the two poles of the battery cell unit 41 through the bracket 43; the electrode assembly 20 is fixed to the front end surface of one bracket 43, and the top cover assembly 30 is temporarily fixed to the rear end surface of the other bracket 43, so that the electrode assembly 20, the top cover assembly 30 and the battery cell unit 41 become a combined body through the bracket 43.

[0064] S30: The combined body obtained in step S20 is pushed into the cavity 11 from the opening 13 at the rear end of the shell 10;

[0065] In this step, the two brackets 43 are respectively provided with a fixing structure for fixing the electrode assembly 20 and the top cover assembly 30, and the fixing structure comprises a buckle structure or a glue bonding structure, etc., and the longitudinal two ends of the battery cell unit 41 are respectively fixed by a pair of brackets 43. The electrode assembly 20, the top cover assembly 30 and the battery cell unit 41 become a relatively stable overall structure. After the above combined body is pushed into the cavity 11, the electrode assembly 20 is correspondingly pushed to the mounting hole 12 of the end wall 14 on the front side of the shell 10, and the outer shape structure of the bracket 43 corresponds to the shape of the cavity 11, so that the combined body is kept in a predetermined position after being pushed in.

[0066] Please refer to Figure 17As shown, the second stepped portion 215 of the substrate 21 of the electrode assembly 20 is received within the inner groove 142 of the end wall 14 and overlaps with the lower side of the protruding edge 141. The bottom surface of the second stepped portion 215 of the substrate 21 is flush with the inner wall surface of the end wall 14, and the top surface of the first stepped portion 214 is flush with the outer surface of the end wall 14. That is, the thickness of the first stepped portion 214 is the same as the thickness of the end wall 14, and the edge of the first stepped portion 214 is in close contact with the edge of the mounting hole 12. There is a certain gap between the edge of the second stepped portion 215 and the edge of the inner groove 142.

[0067] Key references Figure 6 , Figure 13 As shown, the base plate 21 of the top cover assembly 30 closes the opening 13 of the outer shell 10, and the edge fastening groove 218 fits against the edge of the opening 13 of the outer shell 10 for limiting.

[0068] S40: The substrate 21 of the electrode assembly 20 is welded and fixed together with the end wall 14, and the substrate 21 of the top cover assembly 30 is welded and fixed together with the edge of the opening 13 of the outer shell 10.

[0069] In this step, the electrode assembly 20 is irradiated with a laser from the front side of the end wall 14 at the contact point between the first step portion 214 and the mounting hole 12, and a welding zone S is formed by welding around the perimeter, so that the substrate 21 of the electrode assembly 20 and the end wall 14 are sealed and fixed as a whole.

[0070] During laser irradiation, the second stepped portion 215 can block leaked laser light, preventing it from leaking into the cavity 11 and damaging the battery cell 41. Simultaneously, the second stepped portion 215, when in contact with the protruding edge 141, also serves as an initial positioning element.

[0071] In one embodiment, the protruding edge 141 and the upper end of the first stepped portion 214 are provided with a groove structure, and solder is added in the groove structure to increase the stability and operability of the welding.

[0072] The welding of the top cover assembly 30 to the edge of the opening 13 is prior art. For details, please refer to the applicant's published patent technology 202323075601.2, which will not be repeated here.

[0073] Compared with the prior art, the electrode assembly, the secondary battery cell and the manufacturing method thereof of the application, by only setting the opening 13 at one end of the shell 10 and the closed end wall 14 at the other end, only the mounting hole 12 needs to be opened on the end wall 14, so that the cell unit 41, the electrode assembly 20 and the top cover assembly 30 are first electrically connected through the adapter piece 42 and then inserted and assembled from one end of the shell 10, and finally the electrode assembly 20 and the top cover assembly 30 are welded to the mounting hole 12 and the opening 13, which simplifies the assembly difficulty and improves the processing efficiency.

[0074] The main point is that the electrode assembly 20 is attached on the end wall 14 from the inside to the outside, and is welded by external laser irradiation, which simplifies the assembly process and takes into account the feasibility of laser welding. Compared with the prior art, both top cover assemblies 30 need to be externally mounted and welded, so that the welding of the adapter piece 42 is simpler and more feasible.

[0075] In another embodiment, as shown in Figure 19 The end wall 14 is shown as a point edge folded inward from the outer peripheral wall 15 of the shell to support the electrode assembly 20 inserted from the inside to the outside, that is, the mounting hole 12 is a square hole or other larger shape hole and is adapted to the shape of the shell 10, that is, the shape of the electrode assembly 20 is closer to the shape of the top cover assembly 30. However, regardless of the manifestation, the focus of the application is that the electrode assembly 20 is inserted from one side of the opening 13 end of the shell 10 to the mounting hole 12 at the other end opposite to the opening 13.

[0076] The application also provides a power utilization equipment, which is an electric vehicle, an energy storage equipment or the like.

[0077] The technical features of the above embodiments can be combined in any way. In order to make the description concise, not all possible combinations of the technical features in the above embodiments are described, but as long as the combinations of the technical features do not exist contradictory, they should be considered as the scope of the description.

[0078] The above embodiments only express the preferred implementation of the application, and the description is more specific and detailed, but it should not be understood as a limitation on the scope of the application. It should be noted that for ordinary skilled persons in the art, without departing from the concept of the application, a number of modifications and improvements can be made, which are within the scope of the application. Therefore, the protection scope of the application patent should be subject to the appended claims.

Claims

1. A secondary battery cell, characterized by comprising: Comprising The shell comprises a peripheral wall surrounding a cavity, an end wall at least partially closing the front end of the peripheral wall, an opening formed through the rear end of the peripheral wall, and a mounting hole formed through the end wall; the cross section of the opening is consistent with the cross section of the cavity; The electrode assembly comprises a substrate with a first through hole formed therethrough, and a pole column fixed in the mounting hole; The top cover assembly is welded to the opening of the shell; The battery cell unit is electrically connected to the electrode assembly and the top cover assembly at the front and rear ends, respectively; The battery cell unit, the electrode assembly, and the top cover assembly are fixed together and loaded into the cavity from one end of the opening, the edge of the substrate of the electrode assembly is limited inside the end wall of the peripheral edge of the mounting hole and is welded integrally with the end wall, and the top cover assembly is welded to the opening and closes the opening.

2. The secondary battery cell according to claim 1, characterized by The front and rear ends of the battery cell unit are fixed by a support, and the electrode assembly and the top cover assembly are respectively electrically connected to the battery cell unit by an adapter piece and then fixed to the support.

3. The secondary battery cell according to claim 1, characterized by The inner surface of the end wall at the edge of the mounting hole is recessed to form an inner groove and a convex edge, the edge of the substrate of the electrode assembly is clamped into the inner groove and is limited inside the convex edge, and the edge of the substrate is welded and fixed with the convex edge.

4. The secondary battery cell according to claim 3, characterized by The substrate of the electrode assembly comprises a base part, a first through hole formed through the base part, a first step part and a second step part arranged in the radial direction outward from the outer surface of the base part in sequence, the second step part is fitted in the inner groove of the end wall and is attached inside the convex edge, the first step part is in the same horizontal plane as the outer surface of the end wall, and the outer edge of the first step part is attached with the inner edge of the convex edge, and the first step part and the convex edge are welded and sealed at the attachment position.

5. The secondary battery cell according to claim 4, characterized by The convex edge and the outer edge of the first step part are provided with a groove structure, the groove structure is filled with solder, and the solder is melted to achieve sealed welding.

6. The secondary battery cell according to claim 4, wherein The surface of the first step part or the outer surface of the base part is higher than the surface of the first step part.

7. The secondary battery cell according to claim 4, wherein The inner and outer sides of the base part at the peripheral edge of the first through hole are respectively provided with an inner ring groove and an outer ring groove, the inner diameter of the inner ring groove is greater than the inner diameter of the outer ring groove, the electrode assembly further comprises a separation pad limited in the outer ring groove and an insulating member limited in the inner ring groove, and the pole column comprises a column body, a lower limiting part protruding radially outward from the lower end of the column body and limited below the insulating member and the inner ring groove, an upper limiting part folded outward from the upper end of the column body and pressed on the separation pad and above the outer ring groove, and a sealing ring pressed between the lower limiting part and the surface of the inner ring groove.

8. The secondary battery cell according to claim 7, characterized by The insulating member comprises a vertically extending connecting body, a separation part extending radially inward from the upper end of the connecting body, a third through hole formed through the separation part, and an insulating main body extending radially outward from the lower end of the connecting body, the connecting body and the separation part are limited in the inner ring groove, the separation part and the connecting body separate the substrate and the pole column, the insulating main body covers the lower surface of the substrate, and the lower limiting part is limited in the connecting body.

9. The secondary battery cell according to claim 7, wherein The isolation pad comprises a horizontal pad ring supported on the outer ring groove surface, a second through hole formed through the horizontal pad ring, an upper edge extension part extending upward from the outer edge of the horizontal pad ring, and a lower edge extension part extending downward from the inner edge of the horizontal pad ring, the upper limiting part of the pole post is crimped above the horizontal pad ring and is limited within the range of the upper edge extension part, the lower edge extension part extends along the hole wall of the first through hole, and the sealing ring comprises a first sealing ring body crimped between the inner ring groove and the lower limiting part and a second sealing ring body crimped between the lower limiting part and the lower edge extension part.

10. The secondary battery cell according to claim 1, wherein The top cover assembly comprises a base plate and a pole post assembled on the base plate, an edge buckle groove is formed on the inner side outer edge of the base plate, the edge buckle groove is buckled on the outer peripheral wall of the shell and is welded and fixed together.

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