Energy storage device and electric equipment

Abstract

The invention discloses an energy storage device and electric equipment, the energy storage device comprises a shell and a current collecting disc, the shell comprises a side wall and an end wall connected with the side wall, the end wall comprises a body and a welding part, the body is connected with the side wall, the body is provided with a first surface and a second surface which are opposite in the thickness direction, the second surface faces the interior of the shell, and the welding part is welded to the first surface. The welding part protrudes towards the interior of the shell from the second surface; the flow collecting disc is arranged on one side of the second surface and contained in the shell, and the flow collecting disc is welded to the end wall. Therefore, the welding part protrudes towards the interior of the shell from the second surface, the current collecting disc is arranged on one side of the second surface and contained in the shell, and the current collecting disc is welded to the end wall, so that the current collecting disc does not need to penetrate into the end wall, the production process is simple, and the production yield of the energy storage device is improved.

Description

Technical Field

[0001] The present invention relates to the field of battery technology, and more specifically, to an energy storage device and an electrical equipment. Background Art

[0002] In the related art, the energy storage device includes a shell, an end cover, a current collecting plate and an electrode assembly, and one end of the shell is provided with an opening, and the end cover covers the opening. The end cover is provided with a through hole, and the current collecting plate is connected to the electrode assembly and at least partially penetrates through the through hole of the end cover. In the manufacturing process of the energy storage device, the current collecting plate is generally welded to the electrode assembly first, and then at least a part of the current collecting plate is penetrated through the through hole of the end cover, and then the edges of the through hole of the current collecting plate and the end cover are welded. However, due to the high degree of alignment requirements between the through hole of the current collecting plate and the end cover, it is difficult for at least a part of the current collecting plate to penetrate into the through hole of the end cover, which reduces the yield of the energy storage device. Summary of the invention

[0003] The embodiments of the present invention provide an energy storage device and an electrical equipment.

[0004] The energy storage device of the embodiment of the present application includes a shell and a collecting plate, the shell includes a side wall and an end wall connected to the side wall, the end wall includes a body and a welding portion, the body is connected to the side wall, the body has a first surface and a second surface opposite to each other in a thickness direction, the second surface faces the interior of the shell, and the welding portion protrudes from the second surface toward the interior of the shell; the collecting plate is arranged on one side of the second surface and accommodated in the shell, and the collecting plate is welded to the end wall.

[0005] In the energy storage device of the embodiment of the present application, the welding portion protrudes from the second surface toward the interior of the shell, the collecting plate is arranged on one side of the second surface and accommodated in the shell, and the collecting plate is welded to the end wall, so that the collecting plate does not need to penetrate into the end wall, the production process is simple, and the production yield of the energy storage device is improved.

[0006] In some embodiments, the end wall is provided with a recessed groove recessed from the first surface, and the welding portion and the recessed groove partially overlap in the thickness direction. In this way, the recessed groove can reduce the thickness of the end wall at the welding portion, which is beneficial for welding the welding portion to the current collecting plate.

[0007] In some embodiments, the welding portion is formed by a stamping process, so that the welding portion is easy to form, which can reduce the manufacturing cost of the housing.

[0008] In some embodiments, the welding part is provided with a through hole penetrating from the bottom surface of the sink and penetrating the welding part along the thickness direction of the end wall, and the energy storage device further comprises a plugging member, which is arranged in the sink and covers the through hole. In this way, the plugging member can block the through hole and reduce the risk of leakage of the energy storage device.

[0009] In some embodiments, the sink is a stepped sink and includes a first-level sink and a second-level sink, the first-level sink and the second-level sink are arranged in sequence from the second surface to the first surface, the through hole penetrates the welding part from the bottom surface of the first-level sink along the thickness direction of the end wall, and the plugging piece is arranged in the second-level sink. In this way, the plugging piece is arranged in the second-level sink, so that the plugging piece will not interfere with the welding part, effectively reducing the risk of slag generated in the welding part during the welding process interfering with the plugging piece and failing to weld or welding poorly.

[0010] In some embodiments, the plugging member includes an edge portion and a middle portion connected to the edge portion, the edge portion is welded to the body to form a connection portion, and the edge portion is provided with a groove located between the connection portion and the middle portion. In this way, the plugging member is welded to the end wall by welding, which can increase the connection strength between the plugging member and the shell. In addition, the groove can release the stress generated by the welding of the plugging member, thereby improving the stability of the welding between the plugging member and the end wall.

[0011] In some embodiments, the upper surface of the edge portion is flush with the first surface, and the upper surface of the middle portion protrudes from the first surface. Thus, the upper surface of the middle portion protrudes from the first surface of the end wall, which facilitates the connection between the blocking member and the external conductive member.

[0012] In some embodiments, the upper surface of the middle portion protrudes from the first surface by a dimension greater than or equal to 0.1 mm, so that the blocking member is easily connected to the external conductive member.

[0013] In some embodiments, the collector plate includes a plate body and a protrusion protruding from the plate body toward the end wall, and the protrusion is welded to the welding portion. Thus, the arrangement of the protrusion makes it easier to weld and fix the collector plate and the end wall, thereby improving the stability of the connection between the collector plate and the end wall.

[0014] In some embodiments, the welding portion includes a first welding surface facing the current collecting plate, the current collecting plate includes a second welding surface facing the welding portion, and the first welding surface is welded to the second welding surface. In this way, the current collecting plate does not need to penetrate into the end wall, and the center alignment of the current collecting plate and the end wall is not required during the welding process, which improves the welding efficiency.

[0015] The electrical equipment according to the embodiment of the present invention includes the energy storage device described above.

[0016] 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

[0017] 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:

[0018] Figure 1 is a three-dimensional schematic diagram of an energy storage device according to an embodiment of the present invention;

[0019] Figure 2 yes Figure 1 A schematic cross-sectional view of the energy storage device along the AA direction;

[0020] Figure 3 is a three-dimensional schematic diagram of a blocking member according to an embodiment of the present invention;

[0021] Figure 4 It is a three-dimensional schematic diagram of an electrical device according to an embodiment of the present invention.

[0022] Description of reference numerals:

[0023] 100-energy storage device, 10-shell, 11-side wall, 12-end wall, 121-main body, 1211-first surface, 1212-second surface, 122-welding portion, 1221-first welding surface, 123-sink, 1231-first-level sink, 1232-second-level sink, 124-through hole, 20-collecting plate, 21-plate body, 22-protrusion, 23-second welding surface, 30-electrode assembly, 40-sealing member, 41-edge portion, 42-middle portion, 43-connecting portion, 44-groove, 400-electrical equipment. DETAILED DESCRIPTION

[0024] The embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0025] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0026] The disclosure below provides many different embodiments or examples for realizing different structures of the present invention. In order to simplify the disclosure of the present invention, the components and settings of specific examples are described below. Of course, they are merely examples, and the purpose is not to limit the present invention. In addition, the present invention may repeat reference numbers and / or reference letters in different examples, and such repetition is for the purpose of simplification and clarity, and does not itself indicate the relationship between the various embodiments and / or settings discussed. In addition, the present invention provides various specific examples of processes and materials, but those of ordinary skill in the art may appreciate the application of other processes and / or the use of other materials.

[0027] See also Figure 1 and Figure 2 The energy storage device 100 of the embodiment of the present application includes a shell 10 and a collecting plate 20, the shell 10 includes a side wall 11 and an end wall 12 connected to the side wall 11, the end wall 12 includes a body 121 and a welding portion 122, the body 121 is connected to the side wall 11, the body 121 has a first surface 1211 and a second surface 1212 opposite to each other in the thickness direction, the second surface 1212 faces the interior of the shell 10, and the welding portion 122 protrudes from the second surface 1212 toward the interior of the shell 10; the collecting plate 20 is arranged on one side of the second surface 1212 and accommodated in the shell 10, and the collecting plate 20 is welded to the end wall 12.

[0028] In the energy storage device 100 of the embodiment of the present application, the welding portion 122 protrudes from the second surface 1212 toward the inside of the shell 10, the collecting plate 20 is arranged on one side of the second surface 1212 and accommodated in the shell 10, and the collecting plate 20 is welded to the end wall 12, so that the collecting plate 20 does not need to penetrate into the end wall 12, and the center alignment is not required during the welding process of the collecting plate 20 and the end wall 12, the production process is simple, and the production yield of the energy storage device 100 is improved.

[0029] Specifically, the energy storage device 100 may be a cylindrical energy storage device 100 or the like. Figure 2As shown, the energy storage device 100 may also include an electrode assembly 30, and the electrode assembly 30 may include a positive electrode sheet, a negative electrode sheet, and a separator. The energy storage device 100 mainly relies on the movement of metal ions between the positive electrode sheet and the negative electrode sheet to work. The positive electrode sheet includes a positive electrode collector and a positive electrode active material layer, the positive electrode active material layer is coated on the surface of the positive electrode collector, the positive electrode collector not coated with the positive electrode active material layer protrudes from the positive electrode collector coated with the positive electrode active material layer, and the positive electrode collector not coated with the positive electrode active material layer serves as a positive electrode tab.

[0030] Taking lithium-ion batteries as an example, the material of the positive electrode collector can be aluminum, and the positive electrode active material can be lithium cobalt oxide, lithium iron phosphate, ternary lithium or lithium manganese oxide, etc. The negative electrode sheet includes a negative electrode collector and a negative electrode active material layer. The negative electrode active material layer is coated on the surface of the negative electrode collector. The negative electrode collector not coated with the negative electrode active material layer protrudes from the negative electrode collector coated with the negative electrode active material layer. The negative electrode collector not coated with the negative electrode active material layer serves as the negative electrode ear. The material of the negative electrode collector can be copper, and the negative electrode active material can be carbon or silicon, etc. The material of the isolation film can be PP or PE, etc. In addition, the electrode assembly 30 can be a winding structure or a laminated structure, and the embodiments of the present application are not limited to this.

[0031] The shell 10 is an external part of the energy storage device 100. The shell 10 can be made of a relatively strong material such as aluminum alloy. The shell 10 can form the overall shape of the energy storage device 100. For example, when the shell 10 is cylindrical, the energy storage device 100 is also roughly cylindrical. The end of the shell 10 corresponding to the end wall 12 is a closed end, and the end opposite to the end wall 12 is an open end. In other words, Figure 1 As shown, an opening 111 is provided at one end of the side wall 11 opposite to the end wall 12 , and the opening 111 allows components such as the electrode assembly 30 to be installed in the housing 10 .

[0032] The side wall 11 may be cylindrical or square. In one example, the end wall 12 and the side wall 11 may be formed by using the same plate material through a process such as stamping and stretching, so that the end wall 12 and the side wall 11 are an integrally formed structure.

[0033] The edge of the body 121 of the end wall 12 is connected to the side wall 11, and the welding portion 122 of the end wall 12 can be located at the center of the body 121. The welding portion 122 protrudes from the second surface 1212 of the body 121 into the shell 10, so that the end wall 12 is easy to contact with the collecting plate 20, so that the end wall 12 and the collecting plate 20 can be welded by welding methods such as penetration welding, without the need to penetrate the collecting plate 20 into the end wall 12.

[0034] The current collecting plate 20 is a part used to gather the current formed by the electrode assembly 30, so the current collecting plate 20 can be made of metal materials such as copper. The shape of the current collecting plate 20 is similar to the shape of the end wall 12, thereby improving the compactness of the cooperation between the current collecting plate 20 and the end wall 12. For example, the current collecting plate 20 and the end wall 12 can both be parts similar to a disc. The current collecting plate 20 is located on the side of the second surface 1212 of the body 121, that is, the current collecting plate 20 will not be partially embedded in the end wall 12.

[0035] See also Figure 2 In some embodiments, the end wall 12 is provided with a recessed groove 123 which is recessed from the first surface 1211, and the welding portion 122 and the recessed groove 123 partially overlap in the thickness direction. In this way, the recessed groove 123 can reduce the thickness of the end wall 12 at the welding portion 122, which is conducive to welding the welding portion 122 to the collecting plate 20.

[0036] Specifically, the sink 123 may be in a circular groove or other shapes. The sink 123 may be located at the center of the end wall 12, and the welding portion 122 may also be located at the center of the end wall 12, so that the end wall 12 has a larger welding area. The center of the end wall 12 refers to the area around the center of the end wall 12, and the center of the end wall 12 may be the center of gravity or the geometric center of the end wall 12. The notch side of the sink 123 faces away from the collecting plate 20.

[0037] In some embodiments, the welding portion 122 is a structure formed by a stamping process. In other words, the welding portion 122 can be formed by a stamping process. After the end wall 12 is stamped, a sink 123 is formed on one side of the end wall 12, and the welding portion 122 is formed on the other side. In this way, the welding portion 122 is easy to form, which can reduce the manufacturing cost of the housing 10.

[0038] See also Figure 1 and Figure 2 In some embodiments, the welding portion 122 is provided with a through hole 124 which penetrates the welding portion 122 along the thickness direction of the end wall 12 from the bottom surface of the sinking groove 123, and the energy storage device 100 further includes a blocking member 40 which is disposed in the sinking groove 123 and covers the through hole 124. In this way, the blocking member 40 can block the through hole 124, thereby reducing the risk of leakage of the energy storage device 100.

[0039] Specifically, the plugging member 40 can also be called a sealing nail, and the through hole 124 can be set at the center of the welding portion 122. The through hole 124 can be used as the injection hole of the energy storage device 100, or in other words, during the production process of the energy storage device 100, the electrolyte can be injected into the shell 10 through the injection hole. After the injection is completed, the plugging member 40 can be used to block the through hole 124 to prevent liquid leakage. It can be understood that the plugging member 40 is sealed and connected to the side and / or bottom of the sink 123, so as to achieve the effect of the plugging member 40 covering the through hole 124.

[0040] The shape of the blocking member 40 matches the shape of the sink 123 . For example, when the sink 123 is a circular groove, the blocking member 40 can be a circular member, thereby improving the sealing performance of the connection between the blocking member 40 and the end wall 12 .

[0041] See also Figure 2 In some embodiments, the groove 123 is a stepped groove and includes a first-level groove 1231 and a second-level groove 1232. The first-level groove 1231 and the second-level groove 1232 are arranged in sequence from the second surface 1212 to the first surface 1211. The through hole 124 penetrates the welding portion 122 from the bottom surface of the first-level groove 1231 along the thickness direction of the end wall 12, and the sealing member 40 is arranged in the second-level groove 1232.

[0042] In this way, the blocking piece 40 is arranged in the second-level sink 1232, so that the blocking piece 40 will not interfere with the welding part 122, effectively reducing the risk of slag generated by the welding part 122 during the welding process interfering with the blocking piece 40 and causing failure to weld or poor welding.

[0043] Specifically, the first stage sink 1231 and the second stage sink 1232 can be formed by two stretchings, and the size of the first stage sink 1231 is smaller than that of the second stage sink 1232. The blocking member 40 can abut against the bottom surface of the second stage sink 1232, so that the blocking member 40 can be installed more stably.

[0044] See also Figure 1-Figure 3 In some embodiments, the blocking member 40 includes an edge portion 41 and a middle portion 42 connected to the edge portion 41 . The edge portion 41 is welded to the body 121 to form a connecting portion 43 . The edge portion 41 is provided with a groove 44 between the connecting portion 43 and the middle portion 42 .

[0045] Thus, the blocking member 40 is welded to the end wall 12 by welding, which can increase the connection strength between the blocking member 40 and the housing 10. In addition, the groove 44 can release the stress generated by the welding of the blocking member 40 and improve the stability of the welding between the blocking member 40 and the end wall 12.

[0046] Specifically, along the radial direction of the end wall 12, the width of the edge portion 41 is smaller than the width of the middle portion 42. The edge portion 41 can be welded to the body 121 of the end wall 12 along its circumferential edge, and the formed weld can seal the gap formed between the blocking piece 40 and the sink, so that the blocking piece 40 can block the through hole 124.

[0047] The groove 44 may be an annular groove. During the welding process of the edge portion 41, the edge portion 41 near the groove 44 is easily deformed, thereby releasing the stress formed during the welding process of the edge portion 41, reducing the stress concentration in the edge portion 41, and reducing the risk of cracking of the sealing component 40 caused by welding.

[0048] See also Figure 2 In some embodiments, the upper surface of the edge portion 41 is flush with the first surface 1211, and the upper surface of the middle portion 42 protrudes from the first surface 1211. In this way, the upper surface of the middle portion 42 protrudes from the first surface 1211 of the end wall 12, which facilitates the connection between the blocking member 40 and the external conductive member.

[0049] Specifically, the plugging member 40 is a conductive element. For example, the plugging member 40 can be made of a conductive material such as aluminum alloy, so that the plugging member 40 can be conductively connected to the shell 10. The upper surface of the edge portion 41 is flush with the first surface 1211 of the body 121, so that the edge portion 41 can be more easily welded to the body 121 of the end wall 12. As mentioned above, the shell 10 can be used as the positive or negative electrode of the energy storage device 100, and the upper surface of the middle portion 42 can be connected to a conductive member such as an aluminum sheet to achieve the effect of connecting multiple energy storage devices 100 in series or in parallel.

[0050] It should be noted that, in this embodiment, “upper” refers to the side that the first surface 1211 faces.

[0051] In some embodiments, the dimension of the upper surface of the middle portion 42 protruding from the first surface 1211 is greater than or equal to 0.1 mm. For example, the dimension of the upper surface of the middle portion 42 protruding from the first surface 1211 is 0.1 mm, 0.2 mm, 0.3 mm, etc. In this way, it is convenient to connect the blocking member 40 with the external conductive member.

[0052] In some embodiments, the thickness of the middle portion 42 is greater than or equal to 0.8 mm. In this way, the middle portion 42 can meet the welding requirements, reduce welding defects such as perforations after welding, and improve the production yield of the energy storage device 100.

[0053] See also Figure 2In some embodiments, the current collecting plate 20 includes a plate body 21 and a protrusion 22 protruding from the plate body 21 toward the end wall 12, and the protrusion 22 is welded to the welding portion 122. In this way, the setting of the protrusion 22 makes it easier to weld and fix the current collecting plate 20 and the end wall 12, thereby improving the stability of the connection between the current collecting plate 20 and the end wall 12.

[0054] Specifically, along the radial direction of the current collecting plate 20, the size of the protrusion 22 may be smaller than the size of the welding portion 122. The transverse size of the protrusion 22 may be larger than the size of the bottom surface of the first-stage sink 1231, so that the protrusion 22 can be welded to the bottom surface of the first-stage sink 1231 by penetration welding.

[0055] In some embodiments, the welding portion 122 includes a first welding surface 1221 facing the current collecting plate 20, and the current collecting plate 20 includes a second welding surface 23 facing the welding portion 122, and the first welding surface 1221 is welded to the second welding surface 23. In this way, the current collecting plate 20 does not need to penetrate into the end wall 12, and the center alignment of the current collecting plate 20 and the end wall 12 is not required during the welding process, and the welding efficiency is higher. It can be understood that, as discussed above, the welding portion 122 and the current collecting plate 20 can be welded by penetration welding, so the first welding surface 1221 and the second welding surface 23 are welded during the welding process of the welding portion 122 and the current collecting plate 20.

[0056] In one embodiment, the protrusion 22 mentioned above may include a second welding surface 23 .

[0057] In one embodiment, the weld marks formed on the first welding surface 1221 and the second welding surface 23 after welding are located in the area corresponding to the first-level groove 1231. This can reduce the risk of slag generated during the welding process of the first welding surface 1221 and the second welding surface 23 interfering with the sealing part 40 and making it impossible to weld or welding poorly.

[0058] In summary, in one embodiment, the assembly process of the energy storage device 100 is as follows: first, the current collecting plate 20 and the electrode assembly 30 are welded, and then the current collecting plate 20 and the electrode assembly 30 are integrally installed in the shell 10, and then the end wall 12 of the shell 10 and the current collecting plate 20 are welded by penetration welding, and finally the sealing member 40 is sealed with the through hole 124 and welded to the end wall 12.

[0059] See also Figure 4 The electric device 400 of the embodiment of the present invention includes the above energy storage device 100. In this way, the energy storage device 100 can supply power to the electric device 400. The electric device 400 includes but is not limited to a vehicle and an energy storage device.

[0060] In the description of the embodiments of the present invention, the terms "first" and "second" are used for descriptive purposes only and are not to be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the embodiments of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0061] 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" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example 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.

[0062] 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. An energy storage device, characterized in that: include: A shell, the shell comprising a side wall and an end wall connected to the side wall, the end wall comprising a body and a welding portion, the body being connected to the side wall, the body having a first surface and a second surface opposite to each other in a thickness direction, the second surface facing the interior of the shell, and the welding portion protruding from the second surface toward the interior of the shell; A current collecting plate is arranged on one side of the second surface and accommodated in the shell, and the current collecting plate is welded to the end wall.

2. The energy storage device according to claim 1, characterized in that: The end wall is provided with a recessed groove which is recessed from the first surface, and the welding portion and the recessed groove partially overlap in the thickness direction.

3. The energy storage device according to claim 2, characterized in that: The welding portion is a structure formed by a stamping process.

4. The energy storage device according to claim 2, characterized in that: The welding part is provided with a through hole which penetrates from the bottom surface of the sink and passes through the welding part along the thickness direction of the end wall. The energy storage device also includes a blocking member which is arranged in the sink and covers the through hole.

5. The energy storage device according to claim 4, characterized in that: The groove is a stepped groove and includes a first-level groove and a second-level groove. The first-level groove and the second-level groove are arranged in sequence from the second surface to the first surface. The through hole penetrates the welding part from the bottom surface of the first-level groove along the thickness direction of the end wall, and the sealing piece is arranged in the second-level groove.

6. The energy storage device according to claim 4, characterized in that: The blocking member comprises an edge portion and a middle portion connected to the edge portion, the edge portion is welded to the body to form a connecting portion, and the edge portion is provided with a groove located between the connecting portion and the middle portion.

7. The energy storage device according to claim 6, characterized in that: The upper surface of the edge portion is flush with the first surface, and the upper surface of the middle portion is protruding from the first surface.

8. The energy storage device according to claim 7, characterized in that: The dimension by which the upper surface of the middle portion protrudes from the first surface is greater than or equal to 0.1 mm.

9. The energy storage device according to claim 1, characterized in that: The current collecting plate includes a plate body and a protruding portion protruding from the plate body toward the end wall, and the protruding portion is welded to the welding portion.

10. The energy storage device according to claim 1, characterized in that: The welding portion includes a first welding surface facing the current collecting plate, the current collecting plate includes a second welding surface facing the welding portion, and the first welding surface is welded to the second welding surface.

11. An electrical device, characterized in that: The electrical equipment comprises the energy storage device according to any one of claims 1-10.

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