Battery cell structure, method for manufacturing battery cell structure, battery and vehicle

Abstract

The invention discloses a battery cell structure, a manufacturing method of the battery cell structure, a battery and a vehicle. The battery cell structure comprises: a positive electrode cap; a negative electrode cap, provided with a liquid injection hole; an aluminum-plastic film, the aluminum-plastic film is in a cylindrical shape, the upper end of the aluminum-plastic film is sealed and connected to the positive electrode cap, the lower end of the aluminum-plastic film is sealed and connected to the negative electrode cap, the aluminum-plastic film, the positive electrode cap and the negative electrode cap form a sealed space, the liquid injection hole is connected to the sealed space, a winding core is provided in the sealed space, the winding core comprises a positive electrode ear and a negative electrode ear, the positive electrode ear is connected to the positive electrode cap, and the negative electrode ear is connected to the negative electrode cap; and a shell, the shell is in a cylindrical shape, the upper end of the shell is sealed and connected to the positive electrode cap, the lower end of the shell is sealed and connected to the negative electrode cap, and the aluminum-plastic film is located inside the shell. The above-mentioned battery cell structure can inject more electrolyte into the sealed space, thereby improving the performance of the battery cell structure.

Description

Technical Field

[0001] The present invention relates to the field of battery cell technology, and in particular to a battery cell structure, a method for manufacturing the battery cell structure, a battery and a vehicle. Background Art

[0002] At present, the battery cell structure is provided with pole pieces and electrolyte inside, and the pole pieces can react with the electrolyte to make the battery cell structure work. The amount of electrolyte injected will affect the performance of the battery cell structure. In the related art, the battery cell structure is limited by the structure of its steel shell, so that the amount of electrolyte injected is relatively small. Summary of the invention

[0003] The present invention provides a battery cell structure, a method for manufacturing the battery cell structure, a battery and a vehicle.

[0004] The present invention provides a battery cell structure comprising:

[0005] Positive electrode cap;

[0006] The negative electrode cap is provided with a liquid injection hole;

[0007] An aluminum-plastic film, wherein the aluminum-plastic film is in a cylindrical shape, the upper end of the aluminum-plastic film is sealed and connected to the positive electrode cap, the lower end of the aluminum-plastic film is sealed and connected to the negative electrode cap, the aluminum-plastic film, the positive electrode cap and the negative electrode cap form a sealed space, the injection hole is connected to the sealed space, a winding core is arranged in the sealed space, the winding core comprises a positive electrode tab and a negative electrode tab, the positive electrode tab is connected to the positive electrode cap, and the negative electrode tab is connected to the negative electrode cap; and

[0008] The shell is cylindrical, the upper end of the shell is sealed to the positive electrode cap, the lower end of the shell is sealed to the negative electrode cap, and the aluminum-plastic film is located inside the shell.

[0009] In the above-mentioned battery cell structure, the aluminum-plastic film, the positive electrode cap and the negative electrode cap form a sealed space, and electrolyte can be injected into the sealed space in advance before the shell is installed. Since the hardness of the aluminum-plastic film is smaller than that of the shell, more electrolyte can be injected into the sealed space, thereby improving the performance of the battery cell structure.

[0010] In certain embodiments, the positive electrode cap and the negative electrode cap both include:

[0011] A cover plate having a through hole;

[0012] A pole, wherein the through hole is passed through the pole, and the pole is connected to a pole ear of the winding core;

[0013] The inner insulating support is arranged on the inner side of the cover plate and is sealed and connected with the aluminum-plastic film.

[0014] In certain embodiments, the inner insulating support member is sealed to the aluminum-plastic film by heat sealing.

[0015] In some embodiments, a step region is formed on the periphery of the cover plate, and the upper end and the lower end of the shell are partially accommodated in the step region of the positive electrode cap and the step region of the negative electrode cap, respectively.

[0016] In certain embodiments, the positive electrode cap further includes a positive electrode sealing ring, and the positive electrode sealing ring seals and connects the electrode column and the hole wall of the through hole.

[0017] In certain embodiments, the positive electrode cap and the negative electrode cap further include: an external insulating support member, wherein the external insulating support member is sandwiched between the pole and the cover plate.

[0018] In some embodiments, the battery cell structure further includes a positive current collector and a negative current collector, the positive current collector connects the positive electrode column and the positive electrode tab, the negative current collector connects the negative electrode column and the negative electrode tab, and the positive current collector is connected to the positive electrode column by riveting.

[0019] In certain embodiments, the positive electrode current collector and the negative electrode current collector both include:

[0020] A first connecting portion connected to the pole;

[0021] A second connecting portion connected to the tab; and

[0022] The bending portion connects the first connecting portion and the second connecting portion, and the first connecting portion, the second connecting portion and the bending portion are arranged substantially in parallel.

[0023] In certain embodiments, the housing is sealed and connected to the positive electrode cap and the negative electrode cap by roll welding.

[0024] A method for manufacturing a battery cell structure according to an embodiment of the present invention includes:

[0025] The positive electrode cap and the negative electrode cap are respectively sealed and connected to the upper end and the lower end of the aluminum-plastic film, wherein the aluminum-plastic film, the positive electrode cap and the negative electrode cap form a sealed space, and a winding core is arranged in the sealed space;

[0026] injecting electrolyte into the sealed space through the injection hole of the negative electrode cap;

[0027] After the liquid injection is completed, the shell is arranged on the periphery of the aluminum-plastic film, and the upper end and the lower end of the shell are respectively sealed and connected to the positive electrode cap and the negative electrode cap.

[0028] In the above manufacturing method, an aluminum-plastic film is used to achieve a sealed environment for the core roll, and liquid injection can be performed in advance, thereby optimizing the process sequence of assembly and liquid injection, and more electrolyte can be injected, which helps to improve the structural performance of the battery cell.

[0029] A battery according to an embodiment of the present invention includes the battery cell structure according to any of the above embodiments or the battery cell structure manufactured by the above manufacturing method.

[0030] A vehicle according to an embodiment of the present invention includes the battery according to the above embodiment.

[0031] The above-mentioned batteries and vehicles can accommodate more electrolyte in the battery cell structure, thereby improving the performance of the battery cell structure.

[0032] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0034] Figure 1 is a three-dimensional schematic diagram of a battery cell structure according to an embodiment of the invention;

[0035] Figure 2 Schematic diagram of an unfolded portion of a shell and an aluminum-plastic film of a battery cell structure according to an embodiment of the present invention;

[0036] Figure 3 is a cross-sectional schematic diagram of a battery cell structure according to an embodiment of the present invention;

[0037] Figure 4 yes Figure 3 A magnified view of part A;

[0038] Figure 5 yes Figure 3 A magnified view of part B;

[0039] Figure 6 is a schematic diagram of the connection between the positive electrode cap and the positive electrode current collector according to an embodiment of the present invention;

[0040] Figure 7 is another schematic diagram of the connection between the positive electrode cap and the positive electrode current collector according to an embodiment of the present invention;

[0041] Figure 8 is a schematic diagram of the connection between the negative electrode cap and the negative electrode current collector according to an embodiment of the present invention;

[0042] Fig. 9 is another schematic diagram of the connection between the negative electrode cap and the negative electrode current collector according to an embodiment of the present invention;

[0043] Fig.10 Schematic diagram of the connection between the winding core and the positive electrode cap and the negative electrode cap according to an embodiment of the present invention;

[0044] Fig.11 is another schematic diagram of the connection between the winding core and the positive electrode cap and the negative electrode cap according to an embodiment of the present invention;

[0045] Fig.12 Schematic diagram of the structure of the aluminum-plastic film before rolling up according to an embodiment of the present invention. DETAILED DESCRIPTION

[0046] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals represent the same or similar elements or elements having the same or similar functions from beginning to end. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the embodiments of the present invention, and cannot be understood as limiting the embodiments of the present invention.

[0047] Please refer to Figures 1 to 3 A battery cell structure 100 provided in an embodiment of the present invention includes a positive electrode cap 12 , a negative electrode cap 14 , an aluminum-plastic film 16 and a shell 18 .

[0048] The negative electrode cap 14 is provided with a liquid injection hole 20. The aluminum-plastic film 16 is cylindrical, the upper end of the aluminum-plastic film 16 is sealed and connected to the positive electrode cap 12, and the lower end of the aluminum-plastic film 16 is sealed and connected to the negative electrode cap 14. The aluminum-plastic film 16, the positive electrode cap 12 and the negative electrode cap 14 enclose a sealed space 22, the liquid injection hole 20 is connected to the sealed space 22, and a winding core 24 is provided in the sealed space 22. The winding core 24 includes a positive electrode tab 26 and a negative electrode tab 28. The positive electrode tab 26 is connected to the positive electrode cap 12, and the negative electrode tab 28 is connected to the negative electrode cap 14.

[0049] The shell 18 is cylindrical, the upper end of the shell 18 is sealed to the positive electrode cap 12 , the lower end of the shell 18 is sealed to the negative electrode cap 14 , and the aluminum-plastic film 16 is located inside the shell 18 .

[0050] In the above-mentioned battery cell structure 100, the aluminum-plastic film 16, the positive electrode cap 12 and the negative electrode cap 14 enclose a sealed space 22, and the electrolyte can be injected into the sealed space 22 in advance before the housing 18 is installed. Since the hardness of the aluminum-plastic film 16 is smaller than that of the housing 18, more electrolyte can be injected into the sealed space 22, thereby improving the performance of the battery cell structure 100.

[0051] Specifically, the battery cell structure 100 can be a full-ear cylindrical battery cell structure 100. The shell 18 is located at the outermost side of the battery cell structure 100 to protect the internal structure of the battery cell structure 100. The aluminum-plastic film 16 can wrap the core 24 for 360-370°. The shell 18 wraps the core 24 for 360°. The shell 18 is usually relatively hard, and the hardness of the shell 18 is greater than the hardness of the aluminum-plastic film 16. Under the same force, the deformation of the shell 18 is less than the deformation of the aluminum-plastic film 16. Liquid can be first injected into the sealed space 22 surrounded by the aluminum-plastic film 16, the positive cap 12 and the negative cap 14, that is, the electrolyte is injected through the injection hole 20, and the electrolyte can be injected into the sealed space 22 using a large pressure. The aluminum-plastic film 16 can be deformed appropriately to accommodate more electrolyte. After the injection is completed, the injection hole 20 can be sealed and then put into the shell. During the liquid injection process and before the battery is placed in the shell, the winding core 24 can be infiltrated with more electrolyte, thereby improving the performance of the battery cell structure 100 .

[0052] The winding core 24 includes a positive electrode tab 26, a central hole 30 and a negative electrode tab 28. The tab can be flattened by kneading the tab to a height of 2-3 mm on one side, or flattened by patting the tab to a height of 2-3 mm on one side. No specific limitation is made here.

[0053] In certain embodiments, the positive electrode cap 12 and the negative electrode cap 14 both include:

[0054] A cover plate having a through hole;

[0055] A pole, the pole is provided with a through hole, and the pole is connected to the pole ear of the winding core 24;

[0056] The inner insulating support is arranged on the inner side of the cover plate and is sealed and connected with the aluminum-plastic film 16. In this way, a sealed connection can be achieved through the inner insulating support and the aluminum-plastic film 16, and the sealing effect is good.

[0057] For details, please refer to Figure 4 The positive electrode cap 12 includes a positive electrode cover plate 32, the positive electrode cover plate 32 is provided with a first through hole 34, the positive electrode column 36 is provided with the first through hole 34, and the positive electrode column 36 is connected to the positive electrode ear 26 of the winding core 24. The positive electrode inner insulating support 38 is arranged on the inner side of the positive electrode cover plate 32, between the lower surface of the positive electrode cover plate 32 and the exposed part of the positive electrode column 36, and the positive electrode inner insulating support 38 is sealed and connected to the upper end of the aluminum-plastic film 16. In one embodiment, the positive electrode inner insulating support 38 can be a plastic part.

[0058] Please refer to Figure 5The negative electrode cap 14 includes a negative electrode cover plate 40, the negative electrode cover plate 40 is provided with a second through hole 42, the negative electrode pole 44 is penetrated by the second through hole 42, and the negative electrode pole 44 is connected to the negative electrode ear 28 of the winding core 24. The negative electrode inner insulating support 46 is arranged on the inner side of the negative electrode cover plate 40, and the negative electrode inner insulating support 46 is arranged between the upper surface of the negative electrode cover plate 40 and the exposed part of the negative electrode pole 44, and the negative electrode inner insulating support 46 is sealed and connected to the lower end of the aluminum-plastic film 16. In one embodiment, the negative electrode inner insulating support 46 can be a plastic part. The negative electrode pole 44 is interference-fitted with the second through hole 42 (center hole) of the negative electrode cover plate 40 to achieve electrical connection.

[0059] In some embodiments, the inner insulating support is sealed and connected to the aluminum-plastic film 16 by heat sealing, so that the positive electrode cap 12 and the negative electrode cap 14 are easily sealed and connected to the aluminum-plastic film 16.

[0060] Specifically, the outer peripheral wall of the positive electrode inner insulating support 38 is sealed and connected to the upper inner peripheral wall of the aluminum-plastic film 16 by heat sealing. The outer peripheral wall of the negative electrode inner insulating support 46 is sealed and connected to the lower inner peripheral wall of the aluminum-plastic film 16 by heat sealing.

[0061] The inner layer of the aluminum-plastic film 16 can be a polypropylene layer 62 (PP layer), and the inner insulating support can be a plastic part. The melting points of the two are close, and they can be sealed and connected by heat sealing. It is understood that in other embodiments, the inner layer of the aluminum-plastic film 16 can also be other materials, and the inner insulating support can also be other materials, as long as the melting points of the two are close.

[0062] In some embodiments, a step region is formed on the periphery of the cover plate, and the upper end and the lower end of the housing 18 are partially accommodated in the step region of the positive electrode cap 12 and the step region of the negative electrode cap 14, respectively. In this way, the housing 18 can be positioned conveniently.

[0063] Specifically, a first step region 48 is formed around the lower periphery of the positive electrode cover plate 32, and the lower diameter of the positive electrode cover plate 32 is 0.6-2 mm smaller than the upper diameter. The shell 18 may be 0.3-1 mm thick. The upper end of the shell 18 near the upper end surface is accommodated in the first step region 48.

[0064] A second step region 50 is formed around the upper periphery of the negative electrode cover plate 40. The upper diameter of the negative electrode cover plate 40 is 0.6-2 mm smaller than the lower diameter. The shell 18 may be 0.3-1 mm thick. The lower end of the shell 18 is accommodated in the second step region 50 near the lower end surface.

[0065] During installation, the upper end of the housing 18 may be positioned at the first step region 48 , and the lower end may be positioned at the second step region 50 , thereby achieving positioning of the housing 18 .

[0066] Furthermore, the width of the first step area 48 and the second step area 50 are substantially the same as the thickness of the shell 18, that is, the first step area 48 can accommodate the thickness of one layer of the shell 18, and the second step area 50 can accommodate the thickness of one layer of the shell 18, so that after the shell 18 is installed, it will not obviously protrude beyond the range of the positive electrode cap 12 and the negative electrode cap 14.

[0067] In addition, the diameter of the positive electrode inner insulating support 38 is 0.2-0.5 mm smaller than the diameter of the lower part of the positive electrode cover plate 32 to form a third step area, which can just accommodate the thickness of one layer of aluminum-plastic film 16. The thickness of the aluminum-plastic film 16 can be 0.1-0.25 mm.

[0068] The diameter of the negative electrode inner insulating support 46 is 0.2-0.5mm smaller than the upper diameter of the negative electrode cover 40 to form a fourth step area, which can just accommodate the thickness of a layer of aluminum-plastic film 16. The thickness of the aluminum-plastic film 16 can be 0.1-0.25mm. The negative electrode cover 40 is provided with an injection hole 20 at an eccentric position, and the injection hole 20 can be sealed by welding with a sealing nail.

[0069] In some embodiments, the positive electrode cap 12 further includes a positive electrode sealing ring 52, which seals and connects the electrode column with the hole wall of the through hole, so as to achieve insulation and sealing between the positive electrode column 36 and the positive electrode cap 32.

[0070] Specifically, the positive electrode column 36 includes a columnar portion 54 and two convex portions 56 respectively connected to the upper and lower ends of the columnar portion 54. The columnar portion 54 is located in the first through hole 34. The positive electrode sealing ring 52 is sleeved on the outer periphery of the columnar portion 54 and is clamped between the outer periphery of the columnar portion 54 and the hole wall of the first through hole 34. One of the convex portions 56 is located outside the sealed space 22, and the other convex portion 56 is located in the sealed space 22 and connected to the positive electrode ear 26 of the winding core 24.

[0071] It can be understood that in other embodiments, the negative electrode cap 14 can also include a negative electrode sealing ring, and the setting method of the negative electrode sealing ring is similar to the setting method of the positive electrode sealing ring 52. The structure of the negative electrode pole 44 is similar to the structure of the positive electrode pole 36, which will not be expanded in detail here.

[0072] In some embodiments, the positive electrode cap 12 and the negative electrode cap 14 further include an external insulating support member, which is sandwiched between the pole and the cover plate, so as to ensure the insulation between the pole and the cover plate.

[0073] Specifically, the positive electrode cap 12 includes a positive electrode outer insulating support 58, which is sandwiched between the positive electrode column 36 and the positive electrode cover plate 32. Specifically, the positive electrode outer insulating support 58 is annular and sleeved on the outer periphery of the columnar portion 54 of the positive electrode column 36. The positive electrode outer insulating support 58 is clamped by the convex portion 56 located outside the sealed space 22 and the positive electrode cover plate 32.

[0074] The positive electrode column 36 is installed at the center hole position of the positive electrode outer insulating support 58, the positive electrode cover plate 32 and the positive electrode inner insulating support 38.

[0075] The negative electrode cap 14 includes a negative electrode outer insulating support 60, which is sandwiched between the negative electrode column 44 and the negative electrode cover 40. Specifically, the negative electrode outer insulating support 60 is annular and sleeved on the outer periphery of the columnar portion 54 of the negative electrode column 44. The negative electrode outer insulating support 60 is clamped by the convex portion 56 located outside the sealed space 22 and the negative electrode cover 40.

[0076] In certain embodiments, see Fig.12 , along the radial direction from the inside to the outside of the battery cell structure 100, the aluminum-plastic film 16 includes a polypropylene layer 62, an aluminum layer 64 and a nylon layer 66 which are stacked in sequence. In this way, the aluminum-plastic film 16 has a simple structure and is easy to achieve a sealed connection with the positive electrode cap 12 and the negative electrode cap 14.

[0077] Specifically, the polypropylene layer 62 (PP layer) is the inner layer of the aluminum-plastic film 16, and the PP layer can be sealed and connected to the inner insulating support. Since the melting points of the PP layer and the inner insulating support are close, the aluminum-plastic film 16 and the positive electrode cap 12 and the negative electrode cap 14 can be sealed and connected by heat sealing. The sealing method is simple and easy to implement.

[0078] The aluminum layer 64 is the middle layer of the aluminum-plastic film 16 . The aluminum layer 64 can give the aluminum-plastic film 16 a certain shape and plasticity, which is suitable for the aluminum-plastic film 16 to be rolled up and maintain the current shape.

[0079] The nylon layer 66 is the outer layer of the aluminum-plastic film 16 . The nylon layer 66 has good properties such as impact resistance, puncture resistance, heat resistance, friction resistance and insulation, and can effectively protect the battery cell structure 100 and improve the safety of the battery cell structure 100 .

[0080] Please combine Fig.12Before rolling up, the aluminum-plastic film 16 is in the shape of a plate, and from top to bottom, it is composed of a nylon layer 66, an aluminum layer 64, and a PP layer. Most of the upper surface of the aluminum layer 64 is covered by the nylon layer 66, and another small part is covered by the PP layer. The advantage is that after the aluminum-plastic film 16 wraps the winding core 24 for one week, the upper PP layer can be connected with the lower PP layer, and then the two PP layers are connected by heat sealing to form a cylindrical aluminum-plastic film 16 shell with a circumferential side wall seal. The length of the upper PP layer can be 5-15 mm.

[0081] It can be understood that in other embodiments, the aluminum-plastic film 16 may also include other layer structures, and is not limited to the above three-layer structure and material.

[0082] In some embodiments, the battery cell structure 100 further includes a positive current collector 68 and a negative current collector 70, the positive current collector 68 connects the positive electrode post 36 and the positive electrode tab 26, the negative current collector 70 connects the negative electrode post 44 and the negative electrode tab 28, and the positive current collector 68 is connected to the positive electrode post 36 by riveting. In this way, the risk of cold welding caused by welding and the risk of particles such as dust generated during welding falling into the battery cell and causing a short circuit in the battery cell can be avoided.

[0083] Specifically, in the related art, the positive current collector is connected to the positive electrode column by laser penetration welding or torque welding. For laser penetration welding, during the welding process, the center pin is inserted from the center hole of the negative terminal winding core, pressing the welding part of the positive current collector column, and laser penetration welding is performed from the positive electrode column end, so that 100% of the positive electrode column and 40%-60% of the positive current collector are melted and connected at the same time. However, the welding area is inside the battery cell, and the welding effect cannot be checked in real time. When there is a gap between the contact surface of the positive current collector and the positive electrode column, there is a risk of the positive current collector penetrating less than 5%, resulting in a cold weld. For torque welding, during the welding process, the welding head is inserted from the center hole of the negative terminal winding core, pressing the welding part of the positive current collector column, and the welding seat presses the positive electrode column end for torque welding. The positive electrode column and the contact part of the positive current collector are connected by torsional friction. However, the welding area is inside the battery cell, and dust and other particles are generated during the torque welding process, which cannot be effectively detected and removed. There is a risk that particles fall into the battery cell and cause a short circuit in the battery cell.

[0084] In the embodiment of the present invention, the positive current collector 68 is connected to the positive electrode post 36 by riveting, without the need for laser penetration welding or torque welding, thereby solving the problem of cold welding and particles falling into the battery cell and causing the risk of short circuit in the battery cell.

[0085] Specifically, the positive current collector 68 is connected to the protrusion 56 of the positive electrode post 36 located in the sealed space 22 by riveting.

[0086] In some embodiments, the negative current collector 70 is connected to the negative electrode post 44 by riveting, so as to avoid the risk of cold welding caused by welding and the risk of dust and other particles generated during welding falling into the battery cell and causing a short circuit in the battery cell.

[0087] Specifically, the negative electrode current collector 70 is connected to the protrusion 56 of the negative electrode post 44 located in the sealed space 22 by riveting.

[0088] In certain embodiments, the positive current collector 68 and the negative current collector 70 each include:

[0089] A first connecting portion connected to the pole;

[0090] A second connecting portion connected to the tab; and

[0091] The bending portion connects the first connecting portion and the second connecting portion, and the first connecting portion, the second connecting portion and the bending portion are substantially arranged in parallel. In this way, it is easy to realize the connection between the current collecting member and the corresponding cap.

[0092] Specifically, the first connection portion of the positive current collector 68 may be a first positive connection portion 72, the second connection portion of the positive current collector 68 may be a second positive connection portion 74, and the bent portion of the positive current collector 68 may be a positive bent portion 76. The first positive connection portion 72 is connected to the convex portion 56 of the positive electrode column 36 located in the sealed space 22 by riveting, and the second positive connection portion 74 is connected to the positive electrode tab 26 of the winding core 24. The second positive connection portion 74 and the positive electrode tab 26 of the winding core 24 may be connected by laser welding.

[0093] The first connection portion of the negative current collector 70 may be a first negative connection portion 78, the second connection portion of the negative current collector 70 may be a second negative connection portion 80, and the bent portion of the negative current collector 70 may be a negative bent portion 82. The first negative connection portion 78 is connected to the convex portion 56 of the negative electrode column 44 located in the sealed space 22 by riveting, and the second negative connection portion 80 is connected to the negative electrode tab 28 of the winding core 24. The second negative connection portion 80 and the negative electrode tab 28 of the winding core 24 may be connected by laser welding.

[0094] Please refer to Fig.10 Initially, the first positive electrode connection portion 72 is substantially perpendicular to the positive electrode bending portion 76, and the second positive electrode connection portion 74 is substantially perpendicular to the positive electrode bending portion 76. Moreover, the first positive electrode connection portion 72 and the second positive electrode connection portion 74 extend from the upper and lower ends of the positive electrode bending portion 76 in opposite directions. Fig.11, connect the first positive electrode connecting part 72 to the positive electrode column 36, connect the second positive electrode connecting part 74 to the positive electrode ear 26, and then bend the first positive electrode connecting part 72 and the positive electrode bending part 76 from a right angle to 0°, and bend the positive electrode bending part 76 and the second positive electrode connecting part 74 from a right angle to 0°, forming a structure in which the first positive electrode connecting part 72, the second positive electrode connecting part 74 and the positive electrode bending part 76 are basically arranged in parallel.

[0095] Please refer to Fig.10 Initially, the first negative electrode connection portion 78 is substantially perpendicular to the negative electrode bending portion 82, and the second negative electrode connection portion 80 is substantially perpendicular to the negative electrode bending portion 82. Moreover, the first negative electrode connection portion 78 and the second negative electrode connection portion 80 extend from the upper and lower ends of the negative electrode bending portion 82 in opposite directions. Fig.11 , connect the first negative electrode connecting part 78 to the negative electrode column 44, connect the second negative electrode connecting part 80 to the negative electrode ear 28, and then bend the first negative electrode connecting part 78 and the negative electrode bending part 82 from a right angle to 0°, and bend the negative electrode bending part 82 and the second negative electrode connecting part 80 from a right angle to 0°, forming a structure in which the first negative electrode connecting part 78, the second negative electrode connecting part 80 and the negative electrode bending part 82 are basically arranged in parallel.

[0096] In some embodiments, a compression strip is provided on the second connection portion, and the compression strip compresses the second connection portion and the tab, so that the connection strength between the second connection portion and the tab can be ensured.

[0097] For details, please refer to Figure 6 and Figure 7 A positive electrode pressing strip 84 is provided on the upper surface of the second positive electrode connecting portion 74, and the positive electrode pressing strip 84 presses the second positive electrode connecting portion 74 and the positive electrode tab 26. In the illustrated embodiment, three positive electrode pressing strips 84 are provided, which are distributed in a circle, and the second positive electrode connecting portion 74 is provided with a central hole to facilitate the electrolyte to flow into the central hole 30 of the winding core 24.

[0098] Please refer to Figure 8 and Fig. 9 A negative electrode pressing strip 86 is provided on the lower surface of the second negative electrode connecting portion 80, and the negative electrode pressing strip 86 presses the second negative electrode connecting portion 80 and the negative electrode tab 28. In the illustrated embodiment, three negative electrode pressing strips 86 are provided, which are distributed in a circle, and the second negative electrode connecting portion 80 is provided with a central hole to facilitate the electrolyte to flow into the central hole 30 of the winding core 24.

[0099] Furthermore, a positive electrode welding track 88 is provided on the upper surface of the second positive electrode connecting portion 74, and the positive electrode welding track 88 can be used for welding (for example, by laser welding) the second positive electrode connecting portion 74 to the positive electrode tab 26. In the illustrated embodiment, three positive electrode welding tracks 88 are provided, and each positive electrode welding track 88 is located between two adjacent positive electrode clamping strips 84.

[0100] A negative electrode welding track 90 is provided on the lower surface of the second negative electrode connecting portion 80, and the negative electrode welding track 90 can be used for welding (for example, by laser welding) the second negative electrode connecting portion 80 to the negative electrode tab 28. In the illustrated embodiment, three negative electrode welding tracks 90 are provided, and each negative electrode welding track 90 is located between two adjacent negative electrode clamping strips 86.

[0101] In some embodiments, the shell 18 is sealed and connected to the positive electrode cap 12 and the negative electrode cap 14 by roll welding. In this way, the problem of poor shell insertion can be solved.

[0102] Specifically, in the related art, after the positive / negative current collectors are welded to the winding core, the shelling process begins. The coaxiality of the positive current collector and the winding core, as well as the coaxiality of the negative current collector and the winding core will affect the shelling, especially the coaxiality of the negative current collector and the winding core, because the negative current collector and the inner wall of the shell are interference fit. Once the coaxiality is poor, it will lead to poor shelling (NG), resulting in the scrapping of the battery cell.

[0103] In this embodiment, the shell 18 is sealed and connected to the positive electrode cap 12 and the negative electrode cap 14 by roll welding. Even if the coaxiality between the positive electrode collector 68 and the winding core 24 and the coaxiality between the negative electrode collector 70 and the winding core 24 are poor, it will basically not affect the insertion into the shell, or the impact on the insertion into the shell will be small.

[0104] The shell 18 can be made of steel sheet, which wraps the winding core 24 and the aluminum-plastic film 16 360° around. The upper end of the steel sheet is connected to the positive electrode cover plate 32 by first pulse spot welding and then continuous full welding. The lower end of the steel sheet is connected to the negative electrode cover plate 40 by first pulse spot welding and then continuous full welding. After the steel sheet is spliced ​​from head to tail, it is connected by first pulse spot welding and then continuous full welding. The "steel sheet rolling welding" is used instead of the traditional shell entry to solve the problem of poor shell entry caused by poor coaxiality between the positive current collector 68 and the winding core 24 and the poor coaxiality between the negative current collector 70 and the winding core 24.

[0105] After the seam welding is completed, a connection structure is formed at the connection of the steel sheet at both ends, the connection structure extends along the axial direction of the battery cell structure 100, and the connection structure connects the two sides (i.e., the two sides at the beginning and the end) of the shell 18 along the circumference of the battery cell structure 100. In other words, the shell 18 can be formed into a cylindrical shell 18 with a relatively sealed circumferential wall through the connection structure.

[0106] In summary, the battery cell structure 100 according to the embodiment of the present invention can at least achieve the following technical effects:

[0107] 1. The positive electrode cap 12 is connected to the positive electrode collector 68 by riveting, the positive electrode collector 68 is connected to the positive electrode tab 26 of the winding core 24 by laser welding, the negative electrode cap 14 is connected through the negative electrode collector 70 by riveting, the negative electrode collector 70 is connected to the negative electrode tab 28 of the winding core 24 by laser welding, and the riveting method is used instead of the penetration welding and torque welding connection methods of the positive electrode column 36, which solves the problems of cold welding and particles falling into the inside of the winding core 24.

[0108] 2. The present invention adopts a shell 18 (such as steel sheet) to wrap the winding core 24 and the aluminum-plastic film 16 for 360°. The upper end of the shell 18 is connected to the positive electrode cover plate 32 by first pulse spot welding and then continuous full welding. The lower end of the shell 18 is connected to the negative electrode cover plate 40 by first pulse spot welding and then continuous full welding. The "roll welding" method is used instead of the traditional shell entry, which solves the problem of poor shell entry caused by poor coaxiality between the positive current collector 68 and the winding core 24 and the poor coaxiality between the negative current collector 70 and the winding core 24.

[0109] 3. The present invention uses an aluminum-plastic film 16 to wrap the winding core 24 for 360-370° in one circle. The upper end of the aluminum-plastic film 16 is connected to the positive electrode inner insulating support 38 by heat sealing, and the lower end of the aluminum-plastic film 16 is connected to the negative electrode inner insulating support 46 by heat sealing. The head and tail sides of the aluminum-plastic film 16 are connected by heat sealing. The present invention uses the aluminum-plastic film 16 to achieve a sealed environment for the winding core 24, which can be injected in advance, and optimizes the process sequence of assembly and injection.

[0110] A method for manufacturing a battery cell structure 100 provided in an embodiment of the present invention includes:

[0111] The positive electrode cap 12 and the negative electrode cap 14 are respectively sealed and connected to the upper end and the lower end of the aluminum-plastic film 16, and the aluminum-plastic film 16, the positive electrode cap 12 and the negative electrode cap 14 enclose a sealed space 22, and a winding core 24 is arranged in the sealed space 22;

[0112] Inject electrolyte into the sealed space 22 through the injection hole 20 of the negative electrode cap 14;

[0113] After the liquid injection is completed, the housing 18 is arranged on the outer periphery of the aluminum-plastic film 16, and the upper end and the lower end of the housing 18 are respectively sealed and connected to the positive electrode cap 12 and the negative electrode cap 14.

[0114] In the above manufacturing method, the aluminum-plastic film 16 is used to achieve a sealed environment for the winding core 24, and liquid injection can be performed in advance, thereby optimizing the process sequence of assembly and liquid injection, and more electrolyte can be injected, which helps to improve the performance of the battery cell structure 100.

[0115] Specifically, before forming the sealed space 22, the manufacturing method includes:

[0116] 1. The positive electrode cap 12 is connected to the positive electrode current collector 68 by riveting, and the negative electrode cap 14 is connected to the negative electrode current collector 70 by riveting;

[0117] 2. The positive electrode current collector 68 is connected to the positive electrode tab 26 of the winding core 24 by laser welding, and the negative electrode current collector 70 is connected to the negative electrode tab 28 of the winding core 24 by laser welding;

[0118] 3. The first positive electrode connection portion 72 and the positive electrode bending portion 76 are bent from a right angle to 0°, the positive electrode bending portion 76 and the second positive electrode connection portion 74 are bent from a right angle to 0°, the first negative electrode connection portion 78 and the negative electrode bending portion 82 are bent from a right angle design to 0°, and the negative electrode bending portion 82 and the second negative electrode connection portion 80 are bent from a right angle design to 0°.

[0119] When the sealed space 22 is formed, the aluminum-plastic film 16 wraps the winding core 24 for 360-370°, the upper end of the aluminum-plastic film 16 is connected to the positive electrode inner insulating support 38 by heat sealing, the lower end of the aluminum-plastic film 16 is connected to the negative electrode inner insulating support 46 by heat sealing, and the front and rear sides of the aluminum-plastic film 16 are connected by heat sealing;

[0120] After the injection is completed, the shell 18 is located outside the aluminum-plastic film 16, and the shell 18 wraps the winding core 24 and the aluminum-plastic film 16 360 degrees, and the upper and lower ends of the shell 18 are sealed and connected to the positive electrode cap 12 and the negative electrode cap 14 respectively.

[0121] The explanation of the implementation and beneficial effects of the above-mentioned battery cell structure 100 are also applicable to the manufacturing method of this embodiment, and will not be elaborated here in detail to avoid redundancy.

[0122] In some embodiments, the aluminum-plastic film 16 is sealed and connected with the positive electrode cap 12 and the negative electrode cap 14 by heat sealing. In this way, the positive electrode cap 12 and the negative electrode cap 14 are easily sealed and connected with the aluminum-plastic film 16.

[0123] In certain embodiments, the manufacturing method further comprises:

[0124] The battery cell structure 100 with the housing 18 is subjected to a chemical formation process, so that the active material of the battery cell structure 100 can be activated.

[0125] Specifically, in this embodiment, the chemical formation process can be performed after shelling, that is, the manufacturing method of the battery cell structure 100 of this embodiment can be summarized as: aluminum-plastic film 16 sealing → liquid injection → shelling → chemical formation. In addition, in order to achieve better performance of the battery cell structure 100, after liquid injection, an infiltration process can be added, that is, in one embodiment, the manufacturing method of the battery cell structure 100 can be summarized as: aluminum-plastic film 16 sealing → liquid injection → infiltration → shelling → chemical formation.

[0126] In one embodiment, the formation process adopts a negative pressure formation process. It is understood that in other embodiments, the formation process can also adopt a high temperature formation process, a low temperature formation process, a high current formation process, a low current formation process, an open formation process or a closed formation process.

[0127] In some embodiments, after the injection is completed and before the housing 18 is disposed on the periphery of the aluminum-plastic film 16, the manufacturing method further includes:

[0128] The battery cell structure 100 is subjected to a forming process.

[0129] In this way, the active material of the battery cell structure 100 can be activated.

[0130] Specifically, in this embodiment, the chemical formation process can be performed before shelling, that is, the manufacturing method of the battery cell structure 100 of this embodiment can be summarized as: aluminum-plastic film 16 sealing → liquid injection → chemical formation → shelling. In addition, in order to achieve better performance of the battery cell structure 100, after liquid injection, an infiltration process can be added, that is, in one embodiment, the manufacturing method of the battery cell structure 100 can be summarized as: aluminum-plastic film 16 sealing → liquid injection → infiltration → chemical formation → shelling.

[0131] In one embodiment, the formation process adopts a negative pressure formation process. It is understood that in other embodiments, the formation process can also adopt a high temperature formation process, a low temperature formation process, a high current formation process, a low current formation process, an open formation process or a closed formation process.

[0132] In some embodiments, the housing 18 is disposed on the periphery of the aluminum-plastic film 16, and the upper end and the lower end of the housing 18 are respectively sealed and connected to the positive electrode cap 12 and the negative electrode cap 14, including:

[0133] The upper end of the plate is connected to the cover plate of the positive electrode cap 12 by spot welding followed by continuous full welding, and the lower end of the plate is connected to the cover plate of the negative electrode cap 14 by pulse spot welding followed by continuous full welding, and then the two sides of the plate along the circumference of the battery cell structure 100 are welded. In this way, the shell 18 can be set by roll welding, which solves the problem of poor shell entry in the traditional way.

[0134] Specifically, in one embodiment, the plate material may be a steel sheet, that is, it may be inserted into the shell by “steel sheet roll welding”, thereby solving the problem of poor insertion into the shell due to poor coaxiality between the positive electrode current collector 68 and the winding core 24 and poor coaxiality between the negative electrode current collector 70 and the winding core 24 .

[0135] A battery according to an embodiment of the present invention includes the battery cell structure 100 according to any of the above embodiments or a battery cell structure manufactured by the manufacturing method according to any of the above embodiments.

[0136] Specifically, the battery may further include a related protection circuit or other structures. The battery may be formed into a cylindrical battery.

[0137] A vehicle according to an embodiment of the present invention includes the battery according to the above embodiment.

[0138] In the above-mentioned battery and vehicle, the battery cell structure 100 can accommodate more electrolyte, thereby improving the performance of the battery cell structure 100.

[0139] Specifically, multiple batteries (two or more than two batteries) can form a battery pack, and the multiple batteries are connected in series, parallel or series-connected, and the battery pack can be used as a power battery for a vehicle. The vehicle includes but is not limited to a pure electric vehicle, a hybrid vehicle, an extended-range electric vehicle, etc.

[0140] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples" or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiments or examples are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0141] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A battery cell structure, characterized in that: include: Positive electrode cap (12); A negative electrode cap (14) provided with a liquid injection hole (20); an aluminum-plastic film (16), the aluminum-plastic film (16) being in a cylindrical shape, the upper end of the aluminum-plastic film (16) being sealedly connected to the positive electrode cap (12), the lower end of the aluminum-plastic film (16) being sealedly connected to the negative electrode cap (14), the aluminum-plastic film (16), the positive electrode cap (12) and the negative electrode cap (14) enclosing a sealed space (22), the injection hole (20) being connected to the sealed space (22), a winding core (24) being arranged in the sealed space (22), the winding core (24) comprising a positive electrode tab (26) and a negative electrode tab (28), the positive electrode tab (26) being connected to the positive electrode cap (12), and the negative electrode tab (28) being connected to the negative electrode cap (14); and A shell (18), the shell (18) being cylindrical, the upper end of the shell (18) being sealedly connected to the positive electrode cap (12), the lower end of the shell (18) being sealedly connected to the negative electrode cap (14), and the aluminum-plastic film (16) being located inside the shell (18); The aluminum-plastic film (16) comprises a first polypropylene layer (62), a second polypropylene layer, an aluminum layer (64) and a nylon layer (66); the first polypropylene layer (62), the aluminum layer (64) and the nylon layer (66) are stacked in sequence; the first polypropylene layer (62) covers one side surface of the aluminum layer (64); a portion of the other side surface of the aluminum layer (64) is covered by the nylon layer (66) and another portion is covered by the second polypropylene layer; the coverage area of ​​the nylon layer (66) on the aluminum layer (64) is greater than the coverage area of ​​the second polypropylene layer on the aluminum layer (64); the aluminum-plastic film (16) is configured to be wound into a cylindrical shape with a plate-like structure, so that the first polypropylene layer (62) located on the inner side of the aluminum-plastic film (16) cylinder is butted against the second polypropylene layer located on the outer side of the aluminum-plastic film (16) cylinder.

2. The battery cell structure according to claim 1, characterized in that: The positive electrode cap (12) and the negative electrode cap (14) both include: A cover plate having a through hole; A pole, the pole passing through the through hole, the pole being connected to a pole ear of the winding core (24); An inner insulating support member is arranged on the inner side of the cover plate and is sealed and connected to the aluminum-plastic film (16).

3. The battery cell structure according to claim 2, characterized in that: The inner insulating support member is sealed to the aluminum-plastic film (16) by heat sealing.

4. The battery cell structure according to claim 2, characterized in that: A step region is formed on the periphery of the cover plate, and the upper end and the lower end of the shell (18) are partially accommodated in the step region of the positive electrode cap (12) and the step region of the negative electrode cap (14), respectively.

5. The battery cell structure according to claim 2, characterized in that: The positive electrode cap (12) further comprises a positive electrode sealing ring (52), wherein the positive electrode sealing ring (52) seals and connects the electrode column and the hole wall of the through hole.

6. The battery cell structure according to claim 2, characterized in that: The positive electrode cap (12) and the negative electrode cap (14) further include: an external insulating support member, wherein the external insulating support member is sandwiched between the pole and the cover plate.

7. The battery cell structure according to claim 2, characterized in that: The battery cell structure (100) further comprises a positive current collector (68) and a negative current collector (70), wherein the positive current collector (68) connects the positive electrode column (36) and the positive electrode tab (26), and the negative current collector (70) connects the negative electrode column (44) and the negative electrode tab (28), and the positive current collector (68) and the positive electrode column (36) are connected by riveting.

8. The battery cell structure according to claim 7, characterized in that: The positive electrode current collector (68) and the negative electrode current collector (70) both include: A first connecting portion connected to the pole; A second connecting portion connected to the tab; and The bending portion connects the first connecting portion and the second connecting portion, and the first connecting portion, the second connecting portion and the bending portion are arranged substantially in parallel.

9. The battery core structure according to claim 1, characterized in that: The shell (18) is hermetically connected to the positive electrode cap (12) and the negative electrode cap (14) by means of roll welding.

10. A method for manufacturing a battery core structure, characterized in that: include: The positive electrode cap (12) and the negative electrode cap (14) are respectively sealed and connected to the upper end and the lower end of the aluminum-plastic film (16); the aluminum-plastic film (16), the positive electrode cap (12) and the negative electrode cap (14) enclose a sealed space (22); a winding core (24) is provided in the sealed space (22); injecting electrolyte into the sealed space (22) through the injection hole (20) of the negative electrode cap (14); After the liquid injection is completed, the shell (18) is arranged on the outer periphery of the aluminum-plastic film (16), and the upper end and the lower end of the shell (18) are respectively sealed and connected to the positive electrode cap (12) and the negative electrode cap (14); The aluminum-plastic film (16) comprises a first polypropylene layer (62), a second polypropylene layer, an aluminum layer (64) and a nylon layer (66); the first polypropylene layer (62), the aluminum layer (64) and the nylon layer (66) are stacked in sequence; the first polypropylene layer (62) covers one side surface of the aluminum layer (64); a portion of the other side surface of the aluminum layer (64) is covered by the nylon layer (66) and another portion is covered by the second polypropylene layer; the coverage area of ​​the nylon layer (66) on the aluminum layer (64) is greater than the coverage area of ​​the second polypropylene layer on the aluminum layer (64); the aluminum-plastic film (16) is configured to be wound into a cylindrical shape with a plate-like structure, so that the first polypropylene layer (62) located on the inner side of the aluminum-plastic film (16) cylinder is butted against the second polypropylene layer located on the outer side of the aluminum-plastic film (16) cylinder.

11. A battery, characterized in that: A battery cell structure (100) comprising the battery cell structure (100) according to any one of claims 1 to 9 or a battery cell structure (100) manufactured by the manufacturing method according to claim 10.

12. A vehicle, characterized in that: Comprising the battery of claim 11.

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