Lithium battery

Abstract

The lithium battery comprises a shell and a battery cell, the shell comprises a main shell body and a sealing cover plate, the main shell body comprises a bottom plate and a side wall vertically and annularly arranged on the periphery of the bottom plate, and the inner circumferential side of the top of the side wall extends downwards to form a step structure; the edge of the peripheral side of the sealing cover plate covers the step structure to form an accommodating space for placing the battery cell, and the step structure is an annular step formed by continuous extension or a plurality of step sections distributed at intervals. The lithium battery designed by the utility model has good structural strength, can meet the design requirement of compact space of an electronic product, and reduces the manufacturing and assembling difficulty of the lithium battery.

Description

Technical Field

[0001] This utility model relates to the field of energy storage device technology, and in particular to a lithium battery. Background Technology

[0002] Lithium-ion batteries are widely used in various fields such as electronic products, transportation, and industrial equipment due to their high energy density, long lifespan, and lightweight characteristics. Common lithium-ion batteries include square aluminum-cased lithium-ion batteries, cylindrical steel-cased lithium-ion batteries, and aluminum-plastic composite film soft-pack lithium-ion batteries. Aluminum-plastic composite film soft-pack lithium-ion batteries are widely used in electronic products due to their diverse shape designs, which can be designed into irregular structures to meet product space requirements. However, their structural strength is poor, making them easily punctured, resulting in a high number of product scraps due to lithium battery damage. Using standard square aluminum-cased or cylindrical steel-cased lithium-ion batteries in electronic products cannot effectively adapt to the compact internal space, increasing the product's size. Using irregularly shaped aluminum or steel-cased lithium-ion batteries to meet the compact space design requirements of electronic products to enhance structural strength presents challenges during manufacturing and assembly, leading to higher product defect rates during the casing welding process. Utility Model Content

[0003] To address the aforementioned problems, the purpose of this utility model is to design a lithium battery with good structural strength, which can meet the compact space design requirements of electronic products and reduce the difficulty of lithium battery manufacturing and assembly.

[0004] The objective of this utility model is achieved through the following technical solution:

[0005] Design a lithium battery including a casing and a cell. The casing includes a main shell and a sealing cover. The main shell includes a base plate and a side wall vertically arranged around the periphery of the base plate. The inner circumference of the top of the side wall extends downward to form a stepped structure. The edge of the sealing cover seals the stepped structure to form a receiving space for placing the cell. The stepped structure is a continuously extending annular step or a plurality of stepped sections distributed at intervals.

[0006] The lithium battery casing of this solution can be designed according to the spatial structure of the applicable electronic product, such as an irregular shape, to maximize the use of space. The main casing includes a base plate and sidewalls vertically arranged around the base plate. An open assembly surface is formed on one side in the thickness direction. This assembly surface is the largest surface area among the multiple surfaces of the main casing. The shape of the battery cell is the same as that of the base plate, thus the cell can be easily assembled into the receiving space, solving the problem of irregularly shaped cells being difficult to install in the casing, and effectively improving the utilization rate of the receiving space. After the cell is assembled into the receiving space, a sealing cover is used to seal it on the stepped structure, and the main casing and the sealing cover are welded together using laser welding to form a whole. To ensure the consistency of the connection position between the sealing cover and the main casing, a stepped structure is set downwards on the top of the inner side wall of the main casing near the receiving space to restrict and position the sealing cover, ensuring that there is no relative movement between the two during welding, improving welding quality, and thus enhancing the stability of the lithium battery. The lithium battery designed in this solution has good structural strength, can meet the compact space design requirements of electronic products, and reduces the difficulty of lithium battery manufacturing and assembly.

[0007] Furthermore, the base plate is an irregular shape formed by splicing together at least one of polygons, ellipses, and circles.

[0008] The shape of the base plate determines the basic shape of the battery. Depending on the spatial structure of the electronic product, the battery can be set to an irregular shape, such as a combination of one or more polygons, ellipses, or circles, to better adapt to the spatial structure of the electronic product.

[0009] Furthermore, the main housing and / or sealing cover are provided with explosion-proof wires.

[0010] Explosion-proof lines are pre-designed mechanical weakening structures on the outer casing, designed to directionally rupture under abnormal conditions such as thermal runaway. When the internal pressure or temperature of the battery exceeds a threshold, the explosion-proof line, due to its lower structural strength, ruptures first, forming a controllable pressure relief channel and preventing the danger caused by random rupture of the entire casing. Explosion-proof lines are installed on the sealing cover, or on the side wall or bottom surface of the main casing. The shape of the explosion-proof line can be designed as straight, arc, wave, cross, etc., and the cross-section can be a V-groove or U-groove. The groove depth is designed according to the thickness of the sealing cover or main casing and the required pressure threshold.

[0011] Furthermore, the sealing cover plate is provided with a plurality of reinforcing ribs spaced apart on the side facing the main housing, and the explosion-proof line is located between two adjacent reinforcing ribs.

[0012] In this design, the thickness of the sealing cover is generally between 0.05-10mm. Due to its thinness, it is prone to deformation. Therefore, multiple reinforcing ribs are spaced apart on the side of the sealing cover facing the main housing. These ribs are in a straight line shape. After the sealing cover is welded to the main housing, the overall strength of the housing is also improved. In addition, the explosion-proof wire is located in the area between two adjacent reinforcing ribs to avoid the groove depth of the explosion-proof wire from adversely affecting the reinforcing ribs.

[0013] Furthermore, two connection holes are provided on the side wall, and the outer shell also includes two conductive components, which are respectively installed through the two connection holes.

[0014] Two connection holes are formed on the side wall of the main housing. These holes can be formed directly during the die-casting process of the main housing or formed through subsequent machining. The two conductive components are a positive and a negative conductive component, respectively, which are electrically connected to the positive and negative tabs of the battery cell. The conductive components are installed within the connection holes and are insulated from the main housing. The conductive components can be conductive post assemblies, riveted to the connection holes; or they can be conductive sheet assemblies, welded to the inner and outer surfaces of the connection holes. Both conductive components can be conductive post assemblies, or a combination of conductive post and conductive sheet assemblies can be used.

[0015] Furthermore, the sidewall is provided with an injection hole.

[0016] After the battery cell is installed in the casing and welded, electrolyte is injected through the injection port, and then sealed to prevent electrolyte leakage. The side wall of the main casing has an injection port, which can be formed directly during the die casting of the main casing or formed by subsequent machining. The size of the injection port is designed according to actual requirements.

[0017] Furthermore, the injection hole is located between the two connecting perforations.

[0018] In this design, the injection hole is located between the two connecting perforations, which improves the consistency of the outer shell's appearance. In addition, if the injection hole and the connecting perforations are generated by machining, the injection hole and the connecting perforations are located on the same side wall of the main shell, which helps to improve machining efficiency.

[0019] Furthermore, when the edge of the sealing cover is sealed onto the stepped structure, the top surface of the sealing cover away from the receiving space is flush with the top of the side wall of the main housing.

[0020] In this design, the shape of the sealing cover is the same as the shape of the assembly surface of the main housing, the thickness of the sealing cover is the same as the depth of the step, the sealing cover can be embedded and sealed on the step, the top surface of the sealing cover away from the receiving space is flush with the top of the side wall of the main housing, and during welding, the weld is located on the top surface of the outer shell.

[0021] Furthermore, the sealing cover protrudes from the side facing the receiving space to form an abutment platform, which abuts against the stepped structure.

[0022] In this design, the shape and size of the sealing cover are the same as the shape and size of the main housing assembly surface. The side of the sealing cover facing the receiving space protrudes to form an abutment platform, which abuts against the step. The side edge of the sealing cover is flush with the side wall of the main housing. The sealing cover covers the main housing, and during welding, the weld is located on the side of the outer shell.

[0023] Furthermore, the main housing is a die-cast part formed in one piece.

[0024] The lithium battery casing material of this solution can be selected from aluminum alloy and stainless steel. The main casing is cast by a one-piece die-casting process. Therefore, its shape and structure are not limited to the standard shape and structure of square aluminum-cased lithium batteries and cylindrical steel-cased lithium batteries. It can be designed according to the spatial structure of the electronic product to be adapted, such as designing it into an irregular shape, so as to make the most of the space of the electronic product.

[0025] Compared with the prior art, the beneficial effects of this utility model are:

[0026] The lithium battery casing of this solution can be designed according to the spatial structure of the applicable electronic product, such as an irregular shape, to maximize the use of space. The main casing includes a base plate and sidewalls vertically arranged around the base plate. An open assembly surface is formed on one side in the thickness direction. This assembly surface is the largest surface area among the multiple surfaces of the main casing. The shape of the battery cell is the same as that of the base plate, thus the cell can be easily assembled into the receiving space, solving the problem of irregularly shaped cells being difficult to install in the casing, and effectively improving the utilization rate of the receiving space. After the cell is assembled into the receiving space, a sealing cover is used to seal it on the stepped structure, and the main casing and the sealing cover are welded together using laser welding to form a whole. To ensure the consistency of the connection position between the sealing cover and the main casing, a stepped structure is set downwards on the top of the inner side wall of the main casing near the receiving space to restrict and position the sealing cover, ensuring that there is no relative movement between the two during welding, improving welding quality, and thus enhancing the stability of the lithium battery. The lithium battery designed in this solution has good structural strength, can meet the compact space design requirements of electronic products, and reduces the difficulty of lithium battery manufacturing and assembly. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the structure of a lithium battery according to an embodiment of the present invention. Figure 1 .

[0028] Figure 2 This is a schematic diagram of the structure of a lithium battery according to an embodiment of the present invention. Figure 2 .

[0029] Figure 3 This is a schematic diagram of the internal structure of a lithium battery according to an embodiment of the present invention.

[0030] Figure 4 This is a schematic diagram of the main housing structure according to an embodiment of the present invention. Figure 1 .

[0031] Figure 5 for Figure 4 Enlarged view of part A in the middle.

[0032] Figure 6 This is a schematic diagram of the main housing structure according to an embodiment of the present invention. Figure 2 .

[0033] Figure 7 This is a schematic diagram of the structure of a sealing cover plate according to an embodiment of the present invention. Figure 1 .

[0034] Figure 8 This is a schematic diagram of the structure of a sealing cover plate according to an embodiment of the present invention. Figure 2 .

[0035] Illustrations: 1. Outer shell; 11. Main shell; 12. Sealing cover; 13. Explosion-proof wire; 14. Conductive component; 111. Base plate; 112. Accommodation space; 113. Stepped structure; 114. Connection hole; 115. Liquid injection hole; 116. Side wall; 121. Reinforcing rib; 122. Abutment platform; 2. Battery cell. Detailed Implementation

[0036] To facilitate understanding of this invention, a more comprehensive description will be provided below with reference to the accompanying drawings. The drawings illustrate preferred embodiments of the invention. However, this invention can be implemented in many different forms and is not limited to the embodiments described herein.

[0037] like Figures 1 to 8As shown, this embodiment provides a lithium battery, including a casing 1 and a battery cell 2. The casing 1 includes a die-cast integral main casing 11 and a sealing cover 12. The main casing 11 includes a base plate 111 and sidewalls 116 vertically arranged around the periphery of the base plate 111. The shape of the base plate 111 is an irregular shape formed by at least one combination of polygons, ellipses, and circles. This embodiment uses an L-shaped base plate 111 as an example for illustration, therefore the projected shape of the main casing is L-shaped. The material of the main casing 11 can be aluminum alloy or stainless steel, and it is cast using a die-cast integral molding process. Compared with the stamping process, the die-cast integral molding process can manufacture parts with complex shapes. Therefore, the shape and structure of the main casing 11 can be an irregular irregular structure, such as a combination of one or more polygons, ellipses, and circles in projected shape, which can better adapt to the spatial structure of electronic products. The inner circumference of the top of the sidewall 116 extends downward to form a stepped structure 113. The edge of the sealing cover 12 seals the stepped structure 113 to form a receiving space 112 for placing the battery cell. The stepped structure 113 is a continuously extending annular step, or multiple steps spaced apart. In this embodiment, if the stepped structure 113 uses multiple steps spaced apart, the steps can be located at the intersection of the two sidewalls of the main housing 11. The thickness of the main housing 11 ranges from 3 to 1000 mm, the depth of the step ranges from 0.05 to 10 mm, the width of the bottom surface of the step ranges from 0.1 to 10 mm, and the thickness of the sealing cover 12 ranges from 0.05 to 10 mm. The specific dimensions are designed and selected according to the actual application.

[0038] The outer casing 1 is equipped with an explosion-proof line 13. The explosion-proof line 13 is a pre-designed mechanical weakening structure on the outer casing 1, designed for directional rupture under abnormal conditions such as thermal runaway. When the internal pressure or temperature of the battery exceeds a threshold, the explosion-proof line 13, due to its lower structural strength, ruptures first, forming a controllable pressure relief channel and preventing the danger caused by random rupture of the entire casing. The shape of the explosion-proof line 13 can be designed as a straight line, arc, wave, cross, etc., and the cross-section of the explosion-proof line 13 can be a V-groove or a U-groove, with the groove depth designed according to the required pressure threshold. Figure 1 and Figure 2 As shown, the explosion-proof line 13 can be disposed on the sealing cover plate 12, or on the side wall or bottom surface of the main housing 11. The explosion-proof line 13 can be formed directly during the die-casting of the main housing 11, or it can be processed later by laser, stamping, or etching. In this embodiment, the explosion-proof line 13 is disposed on the sealing cover plate 12.

[0039] like Figure 7 and Figure 8As shown, the sealing cover 12 has multiple reinforcing ribs 121 spaced apart on the side facing the main housing 11, and the explosion-proof line 13 is located between two adjacent reinforcing ribs 121. The thickness of the sealing cover 12 is generally within 0.05-10mm. Because its thickness is relatively thin, it is prone to deformation. Therefore, multiple reinforcing ribs 121 are spaced apart on the side of the sealing cover 12 facing the main housing. The reinforcing ribs 121 are in a straight line shape. After the sealing cover 12 is welded to the main housing 11, it can also improve the overall strength of the outer shell 1. In addition, the explosion-proof line 13 is located in the area between two adjacent reinforcing ribs 121 to avoid the groove depth of the explosion-proof line 13 from having an adverse effect on the reinforcing ribs 121.

[0040] like Figures 1 to 6 As shown, two connecting holes 114 are formed on the side wall 116 of the main housing 11. The outer shell 1 also includes two conductive components 14, which are respectively installed through the two connecting holes 114. The connecting holes 114 can be formed directly during the die-casting of the main housing 11, or they can be formed by subsequent machining. The two conductive components 14 are a positive conductive component and a negative conductive component, respectively. The positive and negative conductive components are electrically connected to the positive and negative electrodes of the battery cell 2, respectively. The conductive components 14 are installed through the connecting holes and are insulated from the main housing 11. The conductive components 14 can be conductive post assemblies, installed on the connecting holes 114 by riveting; or they can be conductive sheet assemblies, welded to the inner and outer surfaces of the connecting holes 114 by welding. Both conductive components 14 can be conductive post assemblies, or they can be conductive post assemblies and conductive sheet assemblies respectively. In addition, according to actual needs, the explosion-proof wire 13 can also be processed on the conductive components 14.

[0041] like Figure 4 and Figure 6 As shown, a liquid injection hole 115 is provided on the side wall 116 of the main housing 11, located between two connecting holes 114. After the battery cell 2 is installed into the housing 1 and welded, electrolyte is injected through the liquid injection hole 115, and the system is sealed after injection to prevent electrolyte leakage. The liquid injection hole 115 can be formed directly during the die casting of the main housing 11 or by subsequent machining. The size of the liquid injection hole 115 is designed according to actual requirements. In this embodiment, the liquid injection hole 115 is located between the two connecting holes 114, which can improve the uniformity of the appearance of the housing 1. In addition, if the liquid injection hole 115 and the connecting holes 114 are generated by machining, the liquid injection hole 115 and the connecting holes 114 are located on the same side wall 116 of the main housing 11, which is beneficial to improving processing efficiency.

[0042] like Figure 1 and Figure 2As shown, when the sealing cover 12 is placed on the stepped structure 113, the top surface of the sealing cover 12 facing away from the receiving space 112 is flush with the top of the side wall of the main housing 11. In this embodiment, the shape of the sealing cover 12 is the same as the shape of the bottom plate 111 of the main housing 11, and the thickness of the sealing cover 12 is the same as the depth of the step. The sealing cover 12 can be embedded and sealed on the step. The top surface of the sealing cover 12 facing away from the receiving space 112 is flush with the top of the side wall 116 of the main housing 11. During welding, the weld is located on the top surface of the outer shell 1. In other possible embodiments, the side of the sealing cover 12 facing the receiving space 112 protrudes to form an abutment platform 122, which abuts against the stepped structure 113. The sealing cover 12 has the same shape and size as the bottom plate 111 of the main housing 11. The side of the sealing cover 12 facing the receiving space 112 protrudes to form an abutment platform 122, which abuts against the step. The side edge of the sealing cover 12 is flush with the side wall 116 of the main housing 11. The sealing cover 12 covers the main housing 11. During welding, the weld is located on the side of the outer shell 1.

[0043] In this embodiment, the casing 1 of the lithium battery can be made of aluminum alloy or stainless steel. The main casing 11 is cast using an integral die-casting process. Therefore, its shape is not limited to the standard shapes of square aluminum-cased lithium batteries and cylindrical steel-cased lithium batteries. It can be designed according to the spatial structure of the electronic product, such as an irregular shape, to make the most of the space in the electronic product. An open assembly surface is formed on one side of the main casing 11 in the thickness direction. The assembly surface is the surface with the largest area among the multiple surfaces of the main casing 11. The shape of the battery cell 2 is the same as the shape of the assembly surface. Therefore, the battery cell 2 can be easily assembled into the receiving space, and the utilization rate of the receiving space 112 can be effectively improved. After the battery cell 2 is assembled into the receiving space 112, the assembly surface is sealed with a sealing cover plate 12, and the main casing 11 and the sealing cover plate 12 are welded together by laser welding to form a whole. To ensure the consistency of the connection position between the sealing cover 12 and the main housing 11, a stepped structure 113 is provided downwards on the top of the inner side of the side wall of the main housing 11 near the receiving space 112. This step restricts and positions the sealing cover 12, preventing relative movement during welding, improving welding quality, and thus enhancing the stability of the lithium battery. The lithium battery designed in this embodiment has good structural strength, meeting the compact space design requirements of electronic products, while reducing the difficulty of lithium battery manufacturing and assembly.

[0044] In the description of this utility model, it should be understood that terms such as "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0045] Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, the inclusion of "first," "second," etc., in a feature may explicitly or implicitly include one or more of that feature. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.

[0046] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A lithium battery comprising a housing and an electric cell, characterized in that, The shell comprises a main shell and a sealing cover plate, the main shell comprises a bottom plate and a sidewall vertically annularly arranged around the periphery of the bottom plate, the inner periphery of the top of the sidewall extends downward to form a stepped structure, the edge of the periphery of the sealing cover plate is covered on the stepped structure to form a containing space for placing the battery cell, the stepped structure is an annular step continuously extended or a plurality of steps spacedly arranged.

2. The lithium battery of claim 1, wherein, The bottom plate is irregularly shaped in at least one of the following combinations: polygon, ellipse, circle.

3. The lithium battery of claim 1, wherein, The main shell and / or the sealing cover plate is provided with an anti-explosion wire.

4. The lithium battery of claim 3, wherein, The sealing cover plate is provided with a plurality of reinforcing ribs spacedly arranged on the side facing the main shell, and the anti-explosion wire is located between two adjacent reinforcing ribs.

5. The lithium battery of claim 1, wherein, The sidewall is provided with two connecting perforations, and the shell further comprises two conductive components, and the two conductive components are respectively arranged in the two connecting perforations.

6. The lithium battery of claim 5, wherein, The sidewall is provided with a liquid injection hole.

7. The lithium battery of claim 6, wherein, The liquid injection hole is located between the two connecting perforations.

8. The lithium battery of claim 1, wherein, When the edge of the periphery of the sealing cover plate is covered on the stepped structure, the top surface of the sealing cover plate away from the containing space is flush with the top of the sidewall of the main shell.

9. The lithium battery of claim 1, wherein, The side of the sealing cover plate facing the containing space is convexly formed with an abutting table abutting on the stepped structure.

10. The lithium battery of claim 1, wherein, The main shell is an integrally formed die casting.

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