Battery case assembly and single battery

Abstract

The application relates to a battery shell assembly and a single battery. The battery shell assembly comprises an outer shell, an inner shell and a protection plate. The protection plate is arranged on the side of the inner shell facing the first opening and covers the first opening. The protection plate is welded with the outer shell and the inner shell. Since the protection plate is welded with the outer shell, a high-strength connecting structure is formed between the protection plate and the outer shell, which can effectively resist external impact and vibration, thereby preventing the protection plate and the outer shell from loosening, and ensuring the low resistance and high stability of the external conductive path of the battery, avoiding the decrease of the conductive performance caused by the loosening. Since the protection plate is welded with the inner shell, a high-strength connecting structure is formed between the protection plate and the inner shell, so that the protection plate and the inner shell are connected as a stable whole, effectively preventing the protection plate and the inner shell from loosening, ensuring the reliability of the connection between the protection plate and the inner shell, and avoiding the contact resistance existing in the mechanical connection, reducing energy loss and heat generation.

Description

Technical Field

[0001] This application relates to the field of battery technology, and in particular to a battery casing assembly and a single battery cell. Background Technology

[0002] With the widespread application of lithium-ion batteries in consumer electronics, electric vehicles, and energy storage systems, the requirements for battery safety, cycle life, and reliability are increasing. Cylindrical batteries have become a widely used battery type due to their mature structure, stable manufacturing process, and controllable cost. To improve battery safety, a protection board is typically added outside the cell to provide protection against overcharge, over-discharge, overcurrent, and short circuits.

[0003] Common cylindrical batteries typically employ a contact-type conductive method in their packaging structure to achieve electrical connection between the protection board and the internal battery components. However, during charging and discharging, batteries experience thermal expansion and contraction, which can lead to increased internal resistance or battery failure, and the protection board may also become loose. Utility Model Content

[0004] Therefore, it is necessary to provide a battery assembly and individual battery cells to improve the installation reliability of the protection board, and at the same time avoid the increase in internal resistance or failure of the battery due to thermal expansion and contraction during charging and discharging.

[0005] In a first aspect, this application provides a battery casing assembly, comprising:

[0006] The outer shell has a first receiving cavity and a first opening, the first receiving cavity being in communication with the first opening;

[0007] The inner housing is disposed in the first receiving cavity near the first opening and is connected to the outer housing; and

[0008] A protective plate that covers the first opening and is welded to the outer shell and the inner shell.

[0009] In one embodiment, the inner housing has a second opening, and a support portion is provided at one end of the inner housing having the second opening. The support portion extends outward from the second opening, and the protective plate is provided on the support portion. The support portion has a stop portion that extends in a direction away from the inner housing. A first metal piece is provided on the side of the protective plate, and the first metal piece is welded to at least one of the support portion and the stop portion.

[0010] In one embodiment, the first metal part is welded to the support portion on the side opposite to the first opening.

[0011] In one embodiment, the stop portion is provided with a welding groove, the welding groove having a first groove and a second groove, the first groove being located on the side of the stop portion away from the support portion, and the second groove being located on the side of the stop portion near the protective plate, the welding groove containing solder, and the stop portion being welded to the first metal part through the solder.

[0012] In one embodiment, the stop portion is provided with a welding notch that penetrates the stop portion along its thickness direction. The welding notch contains solder, and the stop portion is welded to the first metal part through the solder.

[0013] In one embodiment, the stop portion has an inclined surface. In the direction from the outer side to the inner side of the stop portion, the inclined surface slopes from the side of the stop portion away from the support portion toward the support portion. The space formed by the inclined surface and the first metal part is filled with solder, and the stop portion is welded to the first metal part by the solder.

[0014] In one embodiment, the protective plate has a second metal component on the side opposite to the inner shell; the outer shell has a first folded edge at one end with the first opening, the first folded edge extends into the first opening, and the first folded edge is pressed onto the second metal component and welded to the second metal component.

[0015] In one embodiment, the battery housing assembly further includes a seal disposed between the inner housing and the outer housing, the seal having a second folded edge disposed between the first folded edge and the edge of the protective plate.

[0016] In one embodiment, the protective plate has a positive electrode post on the side opposite to the inner shell; and / or, the protective plate also has a positive electrode test section.

[0017] Secondly, this application also provides a single battery cell, including a winding core and the aforementioned battery casing assembly, wherein the winding core is disposed within the first receiving cavity and is electrically connected to the protection plate.

[0018] The aforementioned battery casing assembly and individual cells, due to the welding of the protection board to the outer casing, form a high-strength connection structure, making the protection board and outer casing a stable whole. This effectively resists external impacts and vibrations, preventing the protection board from loosening from the outer casing. Simultaneously, it ensures low resistance and high stability of the battery's external conductive path, avoiding a decrease in conductivity due to loose connections. Similarly, the welding of the protection board to the inner casing creates a high-strength connection structure, making the protection board and inner casing a stable whole, effectively preventing loosening and ensuring the reliability of the connection. It also avoids contact resistance present in mechanical connections, reducing energy loss and heat generation. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of a single cell battery according to the first embodiment of this application.

[0020] Figure 2 for Figure 1 The top view of the single cell shown.

[0021] Figure 3 for Figure 2 Sectional view of AA.

[0022] Figure 4 for Figure 3 A magnified view of a portion of point A in the middle.

[0023] Figure 5 for Figure 1 The diagram shows an exploded view of the battery casing assembly of a single battery cell.

[0024] Figure 6 for Figure 5 The diagram shows the structural schematic of the inner casing of a single battery cell.

[0025] Figure 7 This is a cross-sectional view of a single cell battery according to the second embodiment of this application.

[0026] Figure 8 for Figure 7 A magnified view of a portion of point B in the middle.

[0027] Figure 9 This is an exploded view of the battery casing assembly of a single battery cell according to the second embodiment of this application.

[0028] Figure 10 for Figure 9 The diagram shows the structural schematic of the inner casing of a single battery cell.

[0029] Figure 11 This is a cross-sectional view of a single cell battery according to the third embodiment of this application.

[0030] Figure 12 for Figure 11 A magnified view of a portion of point C.

[0031] Figure 13 This is an exploded view of the battery casing assembly of a single battery cell according to the third embodiment of this application.

[0032] Figure 14 for Figure 13 The diagram shows the structural schematic of the inner casing of a single battery cell.

[0033] Explanation of icon numbers:

[0034] 10. Battery casing assembly; 11. Outer casing; 111. First receiving cavity; 112. First opening; 113. First folded edge; 12. Inner casing; 121. Second opening; 122. Second receiving cavity; 123. Support part; 124. Stop part; 1241. Welding groove; 12411. First groove; 12412. Second groove; 1242. Notch; 1243. Inclined surface; 13. Protective plate; 131. Second metal part; 132. Positive electrode post; 133. Positive electrode testing part; 134. First metal part; 14. Sealing part; 141. Second folded edge; 20. Battery body; 21. Core; 22. Positive electrode tab. Detailed Implementation

[0035] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0036] See Figure 1 , Figure 2 and Figure 3 One embodiment of this application provides a single-cell battery, including a battery casing assembly 10 and a battery body 20. The battery body 20 is disposed within the battery casing assembly 10.

[0037] In one embodiment, see Figure 5 The battery casing assembly 10 includes an outer casing 11, an inner casing 12, and a protective plate 13. The protective plate 13 is a PCB board, and both the outer casing 11 and the inner casing 12 are made of metal. Optionally, the outer casing 11 is made of steel, and the inner casing 12 is made of aluminum. Of course, in other embodiments, the outer casing 11 and the inner casing 12 may also be made of other metal materials, and are not limited thereto.

[0038] See Figure 3 and Figure 5 The outer casing 11 has a first receiving cavity 111 and a first opening 112, and the first receiving cavity 111 and the first opening 112 are connected. The battery body 20 is disposed in the first receiving cavity 111. In this embodiment, the outer casing 11 is a hollow cylinder, and the first opening 112 is disposed on one end face of the outer casing 11.

[0039] See Figure 4 and Figure 5 The inner housing 12 is located in the first receiving cavity 111 near the first opening 112 and is connected to the outer housing 11. The protective plate 13 is located on the side of the inner housing 12 facing the first opening 112 and covers the first opening 112. By providing the inner housing 12, the inner housing 12 can support the protective plate 13, increase the rigidity of the end of the battery case assembly 10 with the first opening 112, and improve the impact resistance of the protective plate 13.

[0040] In one embodiment, the protective plate 13 is also welded to the inner housing 12. Specifically, a first metal member 134 is provided on the side of the protective plate 13, and the first metal member 134 is welded to the inner housing 12. Optionally, the first metal member 134 is annular and located on the outer periphery of the protective plate 13. In this way, a high-strength connection structure is formed between the protective plate 13 and the inner housing 12, making the protective plate 13 and the inner housing 12 a stable whole, effectively preventing the protective plate 13 from loosening from the inner housing 12, and ensuring the reliability of the connection between the protective plate 13 and the inner housing 12. In addition, since the protective plate 13 and the inner housing 12 are connected by welding, the contact resistance present in mechanical connections can be avoided, reducing energy loss and heat generation. At the same time, welding is a permanent connection, which can effectively resist the loosening of the connection caused by mechanical vibration and thermal cycle stress.

[0041] In one embodiment, see Figure 4 The inner shell 12 is provided with a second receiving cavity 122. The protective plate 13 is provided with a positive input terminal, which is located in the second receiving cavity 122.

[0042] Further, see Figure 6 The inner shell 12 is also provided with a second opening 121, which communicates with the second receiving cavity 122. In this embodiment, the inner shell 12 is a hollow cylinder, and the second opening 121 is provided on one end face of the inner shell 12 near the first opening 112.

[0043] In one embodiment, see Figure 4 and Figure 6The inner shell 12 has a support portion 123 at one end with a second opening 121. The support portion 123 extends outward from the second opening 121, and the protective plate 13 is provided on the support portion 123. By providing the support portion 123, the support portion 123 provides a mounting reference surface for the protective plate 13, so as to provide stable and uniform support for the protective plate 13, avoiding deformation or stress concentration caused by insufficient support. At the same time, the support portion 123 can restrict the movement of the protective plate 13 away from the first opening 112.

[0044] Furthermore, the edge of the support portion 123 is provided with a stop portion 124, which extends in a direction away from the inner housing 12. By providing the stop portion 124 extending away from the inner housing 12 in the support portion 123, the stop portion 124 can limit the movement of the protective plate 13, preventing the protective plate 13 from radially displacing along the inner housing 12 in the support portion 123. At the same time, during the assembly of the protective plate 13, the annular stop portion 124 can guide the protective plate 13, ensuring that the protective plate 13 can be quickly and accurately installed in place. In addition, under the action of the stop portion 124, the positive terminal 132 can be kept concentric with the outer housing 11.

[0045] Optionally, the protective plate 13 is welded to at least one of the support portion 123 and the stop portion 124. For example, the first metal part 134 is welded to the support portion 123; or, the first metal part 134 is welded to the stop portion 124; or, the first metal part 134 is welded to both the support portion 123 and the stop portion 124.

[0046] In one embodiment, see Figures 11 to 14 The first metal part 134 is welded to the support part 123 on the side opposite to the first opening 112. In this way, the protective plate 13 is welded to the support part 123 through the first metal part 134, realizing the axial connection between the two. This makes the protective plate 13 and the inner shell 12 have a good shear resistance connection, providing stable planar support for the protective plate 13. At the same time, the protective plate 13 can be directly placed on the support part 123 for welding, which is simple and reliable in positioning and helps to improve production efficiency.

[0047] In one embodiment, see Figures 7 to 9 The stop portion 124 is provided with a welding groove 1241. Specifically, the welding groove 1241 is located on the side of the stop portion 124 opposite to the support portion 123. (See reference...) Figure 10 The welding groove 1241 has a first groove 12411 and a second groove 12412. The first groove 12411 is located on one side of the stop portion 124 away from the support portion 123, and the second groove 12412 is located on the inner side of the stop portion 124.

[0048] It should be noted that the inner side of the stop part 124 refers to the side of the stop part 124 that is close to the protective plate 13.

[0049] Understandably, the first slot 12411 serves as the injection port of the welding tank 1241. During welding, solder can be injected into the welding tank 1241 through the first slot 12411. The second slot 12412 serves as the overflow port of the welding tank 1241. When the amount of solder in the welding tank 1241 reaches a certain level, the solder flows through the second slot 12412 to the periphery of the first metal part 134 under pressure, thereby realizing the welding of the protective plate 13 and the inner shell 12.

[0050] Furthermore, at least two welding grooves 1241 are provided, and the at least two welding grooves 1241 are arranged circumferentially around the stop portion 124. In this way, there are at least two welding positions between the protective plate 13 and the stop portion 124, which can improve the firmness of the connection between the protective plate 13 and the inner shell 12.

[0051] In this embodiment, see Figure 10 There are two welding grooves 1241, which are arranged symmetrically.

[0052] In one embodiment, see [reference] Figures 3 to 5 The stop portion 124 is provided with a welding notch 1242, which penetrates the inner and outer surfaces of the stop portion 124 along its thickness direction. It should be noted that the outer surface of the stop portion 124 refers to the side of the stop portion 124 facing away from the protective plate 13. Thus, after the solder fills the welding notch 1242, a through welding pin can be formed, achieving mechanical interlocking, reducing the risk of connection failure, and allowing welding to be completed from a single side, reducing the requirements for the precision and complexity of the welding fixture, simplifying operation, and improving production efficiency.

[0053] Furthermore, at least two welding notches 1242 are provided, and the at least two welding notches 1242 are spaced apart circumferentially along the stop portion 124. In this way, there are at least two welding positions between the protective plate 13 and the stop portion 124, which can improve the firmness of the connection between the protective plate 13 and the inner shell 12.

[0054] Optionally, two welding notches 1242 are provided, and the two welding notches 1242 are symmetrically arranged. Of course, in other embodiments, see [reference needed]. Figure 6 A welding notch 1242 can also be set.

[0055] In another embodiment, see [reference] Figure 12 and Figure 14The stop portion 124 is provided with an inclined surface 1243. In the direction from the outer side to the inner side of the stop portion 124, the inclined surface 1243 slopes from the side of the stop portion 124 away from the support portion 123 toward the support portion 123. In this way, the space formed between the inclined surface 1243 and the first metal part 134 can be used to accommodate the solder, thereby realizing the welding of the inner shell 12 and the protective plate 13.

[0056] In one embodiment, the protective plate 13 is welded to the outer casing 11. This forms a high-strength connection between the protective plate 13 and the outer casing 11, making them a stable whole. This effectively resists external impacts and vibrations, preventing the protective plate 13 from loosening. Simultaneously, the welded joint between the protective plate 13 and the outer casing 11 achieves a microscopic metallurgical bond, forming a reliable gas-liquid seal, preventing electrolyte leakage and the intrusion of external moisture, oxygen, etc., ensuring a stable internal environment for long-term battery operation. Furthermore, because the protective plate 13 and the outer casing 11 are securely connected by welding, the low resistance and high stability of the battery's external conductive path are ensured, avoiding a decrease in conductivity due to loose connections.

[0057] Further, see Figure 4 and Figure 5 A second metal piece 131 is provided on the side of the protective plate 13 facing away from the inner shell 12. A first flange 113 is provided at one end of the outer shell 11 with a first opening 112. The first flange 113 extends into the first opening 112 and is pressed onto and welded to the second metal piece 131. By pressing the first flange 113 onto the second metal piece 131, the first flange 113 can resist displacement of the protective plate 13 due to internal pressure or external impact, thus improving the structural strength and impact resistance of the battery. By welding the first flange 113 to the second metal piece 131, a permanent airtight seal is formed between the protective plate 13 and the outer shell 11, preventing electrolyte leakage and the intrusion of external contaminants. Simultaneously, under the combined action of pressing contact and welding, a stable electrical connection with low resistance and high current capability is ensured between the outer shell 11 and the protective plate 13.

[0058] In one embodiment, see Figure 4 The battery housing assembly 10 also includes a seal 14. The seal 14 is disposed between the inner housing 12 and the outer housing 11. By providing the seal 14, on the one hand, the inner housing 12 and the outer housing 11 are sealed together, and on the other hand, the inner housing 12 and the outer housing 11 are insulated from each other.

[0059] Furthermore, the seal 14 is provided with a second folded edge 141. The second folded edge 141 covers the edge of the protective plate 13, and the first folded edge 113 presses against the edge of the protective plate 13 through the second folded edge 141, so that the first folded edge 113 applies force to the protective plate 13 through a flexible intermediate layer. This can automatically compensate for dimensional tolerances and assembly errors between parts, and ensure that the sealing pressure is evenly distributed across the entire edge of the protective plate 13, thereby forming a stable and reliable airtight seal.

[0060] In one embodiment, see Figure 5 The protective plate 13 has a positive terminal 132 on the side opposite to the inner casing 12. Thus, the positive terminal 132 is the positive output terminal of the single battery cell, which facilitates quick connection with external circuits.

[0061] In one embodiment, see Figure 2 and Figure 5 The protection board 13 also includes a positive electrode testing section 133. Optionally, the positive electrode testing section 133 can be a point. During battery assembly or testing, the positive electrode testing section 133 can be connected to measuring instruments (such as a multimeter, internal resistance meter, or charge / discharge testing equipment) to evaluate the electrical performance of the battery's positive electrode. In this way, the electrical performance of the battery semi-finished or finished product can be tested without damaging the individual cells or performing final packaging.

[0062] In one embodiment, see Figure 3 The battery body 20 includes a winding core 21, a positive electrode tab 22, and a negative electrode nickel sheet. The winding core 21 is disposed within the first receiving cavity 111, and the negative electrode nickel sheet is disposed on the side of the winding core 21 facing away from the inner shell 12, and is electrically connected to the outer shell 11 and the winding core 21. The positive electrode tab 22 is disposed between the winding core 21 and the inner shell 12, and is electrically connected to both the winding core 21 and the inner shell 12.

[0063] In the description of this application, it should be understood that if terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" appear, these terms indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application 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, and therefore should not be construed as a limitation of this application.

[0064] Furthermore, where the terms "first" and "second" appear, these terms are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, where the term "multiple" appears, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0065] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0066] In this application, unless otherwise expressly specified and limited, the use of descriptions such as "above" or "below" the second feature indicates that the first and second features are in direct contact or indirect contact via an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. Similarly, "below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0067] It should be noted that if an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. If an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. If so, the terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used in this application are for illustrative purposes only and do not represent the only possible implementation.

[0068] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0069] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A battery casing assembly, characterized in that, include: The outer shell has a first receiving cavity and a first opening, the first receiving cavity being in communication with the first opening; An inner housing is disposed in the first receiving cavity near the first opening and is connected to the outer housing. as well as A protective plate that covers the first opening and is welded to the outer shell and the inner shell.

2. The battery casing assembly according to claim 1, characterized in that, The inner shell has a second opening, and a support portion is provided at one end of the inner shell with the second opening. The support portion extends outward from the second opening, and the protective plate is provided on the support portion. The support portion has a stop portion that extends away from the inner shell. The protective plate has a first metal part on its side, and the first metal part is welded to at least one of the support part and the stop part.

3. The battery casing assembly according to claim 2, characterized in that, The first metal part is welded to the support portion on the side opposite to the first opening.

4. The battery casing assembly according to claim 2, characterized in that, The stop portion is provided with a welding groove, which has a first groove and a second groove. The first groove is located on the side of the stop portion away from the support portion, and the second groove is located on the side of the stop portion near the protective plate. The welding groove contains solder, and the stop portion is welded to the first metal part through the solder.

5. The battery casing assembly according to claim 2, characterized in that, The stop portion is provided with a welding notch, which penetrates the stop portion along the thickness direction. The welding notch is filled with solder, and the stop portion is welded to the first metal part through the solder.

6. The battery casing assembly according to claim 2, characterized in that, The stop portion has an inclined surface. In the direction from the outer side to the inner side of the stop portion, the inclined surface slopes from the side of the stop portion away from the support portion toward the support portion. The space formed by the inclined surface and the first metal part is filled with solder. The stop portion is welded to the first metal part through the solder.

7. The battery casing assembly according to claim 1, characterized in that, The protective plate has a second metal component on the side opposite to the inner shell; The outer shell has a first folded edge at one end with the first opening. The first folded edge extends into the first opening and is pressed onto the second metal part and welded to the second metal part.

8. The battery casing assembly according to claim 7, characterized in that, The battery casing assembly further includes a sealing element disposed between the inner casing and the outer casing. The sealing element has a second folded edge disposed between the first folded edge and the edge of the protective plate.

9. The battery casing assembly according to any one of claims 1 to 8, characterized in that, The protective plate has a positive electrode post on the side opposite to the inner shell; and / or, the protective plate also has a positive electrode test section.

10. A single-cell battery, characterized in that, It includes a winding core and a battery casing assembly as described in any one of claims 1 to 9, wherein the winding core is disposed within the first receiving cavity and is electrically connected to the protective plate.

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