Single battery

Abstract

The utility model provides a single battery. The single battery comprises a shell; the cover plate assembly is connected with the shell and forms a first accommodating cavity; the cover plate assembly is provided with a positive terminal assembly and a negative terminal assembly; the electrode assembly is electrically connected with the positive terminal assembly and the negative terminal assembly in the first accommodating cavity; the lithium supplementing structure is located in the first containing cavity and comprises a lithium source, an insulating support and a conductive part, and the insulating support is located between the negative terminal assembly and the electrode assembly; the conductive part is electrically connected with a lithium source tab extending from the lithium source, and is positioned between the insulating bracket and the negative terminal assembly; when the electrode assembly expands, the insulation support is pushed to drive the conductive part to be in contact with the negative terminal assembly for conduction. According to the lithium supplement structure, the electrode assembly is in contact conduction with the negative terminal assembly in the expansion process, so that lithium supplement is performed on the negative electrode to reduce lithium loss in the battery, the battery capacity is favorably maintained, and the service life of the battery is prolonged.

Description

Technical Field

[0001] This application relates to the field of battery cell technology, and more particularly to a single-cell battery. Background Technology

[0002] When a lithium-ion battery is activated, it consumes lithium ions inside the battery and forms an SEI (Solid Electrolyte Interphase) film on the surface of the negative electrode. However, during the battery's charge-discharge cycle, the SEI film on the negative electrode surface continues to thicken and continuously consumes lithium ions. If the battery is not replenished with lithium, its capacity and cycle performance will gradually decrease, thus affecting its lifespan. Utility Model Content

[0003] In view of the above, this application aims to provide a single-cell battery to solve some or all of the aforementioned technical problems.

[0004] For the purposes described above, this application provides a single-cell battery, comprising:

[0005] case;

[0006] A cover plate assembly is connected to the housing and forms a first receiving cavity; the cover plate assembly is provided with a positive terminal component and a negative terminal component;

[0007] The electrode assembly is electrically connected to the positive terminal assembly and the negative terminal assembly respectively within the first receiving cavity;

[0008] The lithium replenishment structure, located within the first accommodating cavity, includes a lithium source, an insulating support, and a conductive component. The insulating support is located between the negative terminal assembly and the electrode assembly. The conductive component is electrically connected to a lithium source tab extending from the lithium source and is connected to the end of the insulating support away from the electrode assembly.

[0009] When the electrode assembly expands, it pushes the insulating bracket to cause the conductive component to make contact with the negative terminal assembly and conduct electricity.

[0010] As can be seen from the above, the single-cell battery provided in this application has a lithium replenishment structure that includes a lithium source, an insulating support, and conductive components. The structure is simple and the assembly is relatively easy. After the battery has undergone multiple charge-discharge cycles, the electrode assembly expands compared to the activated state, which pushes the insulating support to move the conductive components toward the negative terminal assembly. Once the conductive components contact the negative terminal assembly, they are connected to the lithium source. After the connection is established, the lithium source can replenish lithium to the negative electrode, which can reduce lithium loss inside the battery, help maintain battery capacity, and extend its service life. In addition, since this lithium replenishment structure requires the electrode assembly to expand to trigger the lithium replenishment process, the lithium replenishment structure will not interfere with the electric cycling process. It also avoids premature connection between the lithium replenishment structure and the negative terminal assembly, which could lead to excessively high lithium ion concentration inside the battery and lithium plating, thus improving the performance and quality of the battery. Attached Figure Description

[0011] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0012] Figure 1 This is a perspective view of the battery in an embodiment of this application;

[0013] Figure 2 This is a partial cross-sectional view of the battery in an embodiment of this application;

[0014] Figure 3 This is a perspective view of the cover plate assembly in an embodiment of this application;

[0015] Figure 4 This is a bottom view of the cover plate assembly in an embodiment of this application;

[0016] Figure 5 This is a partial cross-sectional view of the cover plate assembly in an embodiment of this application;

[0017] Figure 6 This is a schematic diagram of the first lithium replenishment structure and negative terminal component in the embodiments of this application;

[0018] Figure 7 This is a schematic diagram of the second lithium replenishment structure and the negative terminal component in the embodiments of this application;

[0019] Figure 8 This is a schematic diagram of the third lithium replenishment structure and the negative terminal component in the embodiments of this application;

[0020] Figure 9 This is a schematic diagram showing the position of the metal spring in the second receiving cavity in an embodiment of this application;

[0021] Figure 10 This is a perspective view of the electrode assembly in an embodiment of this application;

[0022] Figure 11 This is a schematic diagram of the composition of the electrode assembly in an embodiment of this application;

[0023] Figure 12 This is a schematic diagram showing the positional relationship between the lithium source and the negative electrode in an embodiment of this application.

[0024] Explanation of reference numerals in the attached figures:

[0025] 1. Shell; 101. First receiving cavity;

[0026] 2. Cover plate assembly; 201. Positive terminal assembly; 202. Negative terminal assembly; 2021. Negative terminal; 2022. Negative terminal adapter piece; 210. Cover body; 220. Lower plastic; 222. Second receiving cavity;

[0027] 3. Electrode assembly; 310. Positive electrode plate; 311. Positive electrode tab; 320. Separator; 330. Negative electrode plate; 331. Negative electrode tab; 340. Active layer;

[0028] 4. Lithium replenishment structure; 410. Lithium source; 411. Lithium source tab; 420. Insulating support; 430. Conductive component; 431. Conductive connecting piece; 432. Metal spring;

[0029] 5. First shrapnel;

[0030] 6. Second shrapnel. Detailed Implementation

[0031] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with specific embodiments and the accompanying drawings.

[0032] It should be noted that, unless otherwise defined, the technical or scientific terms used in the embodiments of this application should have the ordinary meaning understood by one of ordinary skill in the art to which this application pertains. The terms "first," "second," and similar terms used in this application do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word covers the element or object listed following the word and its equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are only used to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0033] The lifespan of individual lithium-ion batteries is a crucial factor in evaluating their overall performance and cost-effectiveness. Specifically, both the electrolyte and the positive electrode of a lithium-ion battery contain lithium. During the initial charge activation, a dense SEI film forms on the surface of the negative electrode, allowing lithium ions to pass through and providing effective protection. However, as the number of battery cycles increases, the SEI film on the negative electrode surface thickens, causing the electrode assembly to expand and continuously consume lithium ions. This leads to a gradual decrease in the reversible lithium content within the battery, resulting in capacity decay and a shortened lifespan.

[0034] This application provides a single-cell battery, combined with Figures 1-12 The content shown provides a detailed description of the single battery cell.

[0035] A single-cell battery includes a housing 1, a cover assembly 2, an electrode assembly 3, and a lithium replenishment structure 4. The cover assembly 2 is connected to the housing 1 to form a first receiving cavity 101. The cover assembly 2 is provided with a positive terminal sub-assembly 201 and a negative terminal sub-assembly 202. The electrode assembly 3 is electrically connected to the positive terminal sub-assembly 201 and the negative terminal sub-assembly 202 respectively within the first receiving cavity 101. The lithium replenishment structure 4 is located within the first receiving cavity 101 and includes a lithium source 410, an insulating support 420, and a conductive component 430. The insulating support 420 is located between the negative terminal sub-assembly 202 and the electrode assembly 3. The conductive component 430 is electrically connected to a lithium source tab 411 extending from the lithium source 410 and is located between the insulating support 420 and the negative terminal sub-assembly 202. When the electrode assembly 3 expands, it pushes the insulating support 420 to cause the conductive component 430 to make contact with the negative terminal sub-assembly 202 and conduct electricity.

[0036] Specifically, such as Figure 1 and Figure 2 As shown, Figure 1 This is a perspective view of the battery in an embodiment of this application. Figure 2 This is a partial cross-sectional view of the battery in an embodiment of this application. The cover plate assembly 2, after being connected to the top of the housing 1, can form a sealed first receiving cavity 101 to accommodate the electrolyte, electrode assembly 3, lithium replenishment structure 4, and other components, providing a stable electrochemical environment for the electrode assembly 3.

[0037] For example, the housing 1 may be made of aluminum or its alloy, ensuring that the housing 1 has sufficient mechanical strength, provides excellent corrosion resistance, and also reduces the weight of the battery.

[0038] For example, the inner surface of the housing 1 may be coated with a chemically stable, corrosion-resistant and insulating coating such as polyurethane or ceramic coating, which is beneficial to extending the service life of the housing 1.

[0039] Specifically, such as Figures 1-5 As shown, Figure 3 This is a perspective view of the cover plate assembly 2 in the embodiments of this application. Figure 4 This is a bottom view of the cover plate assembly 2 in an embodiment of this application. Figure 5 This is a partial cross-sectional view of the cover plate assembly 2 in an embodiment of this application. In addition to sealing the first receiving cavity 101, the cover plate assembly 2 also includes a positive terminal assembly 201 and a negative terminal assembly 202. The positive terminal assembly 201 and the negative terminal assembly 202 are electrically connected to the positive electrode tab 311 and the negative electrode tab 331 extending from the electrode assembly 3, respectively. Through these two electrode terminal assemblies, the battery can be electrically connected to external electrical equipment to achieve energy storage or supply.

[0040] Specifically, such as Figure 2 As shown, the electrode assembly 3 is housed in the first receiving cavity 101 and is electrically connected to the positive terminal assembly 201 and the negative terminal assembly 202 through its extended positive electrode tab 311 and negative electrode tab 331, respectively.

[0041] Specifically, such as Figures 2-8 As shown, Figure 6 This is a schematic diagram of the first lithium replenishment structure 4 and the negative terminal component 202 in the embodiments of this application. Figure 7 This is a schematic diagram of the second lithium replenishment structure 4 and the negative terminal sub-component 202 in the embodiments of this application. Figure 8 This is a schematic diagram of the third lithium replenishment structure 4 and the negative terminal component 202 in the embodiments of this application.

[0042] More specifically, the lithium replenishment structure 4 in the first receiving cavity 101 includes a lithium source 410, an insulating support 420, and a conductive component 430. After the battery is activated, during a single charge and discharge cycle, although the SEI film formed on the surface of the negative electrode causes the electrode assembly 3 to expand, there is a gap between the conductive component 430 and the negative terminal assembly 202, and the two remain in a non-conductive state without lithium ion replenishment. With multiple charge and discharge cycles, the SEI film continues to thicken and is accompanied by the generation of side reaction gases, causing the volume of the electrode assembly 3 to expand further than when activated. At this time, the expanded electrode assembly 3 can push the insulating support 420 to move the conductive component 430 toward the negative terminal assembly 202, so that the conductive component 430 is close to the negative terminal assembly 202. When the two come into contact, the negative terminal assembly 202 can be interconnected with the lithium source 410, so that the lithium deposited in the first receiving cavity 101 by the lithium source 410 can replenish the negative electrode with lithium, thereby reducing the lithium loss inside the battery.

[0043] Furthermore, the lithium replenishment structure 4 is triggered by the expansion of the electrode assembly 3 after the battery has undergone multiple electrical cycles, which triggers the lithium source 410 to replenish lithium to the negative electrode of the battery. Therefore, in the early stage of battery use, the electrode assembly 3 will not trigger the lithium replenishment structure 4 to replenish lithium through the negative electrode. This will prevent the lithium ion concentration from becoming too high and causing lithium plating, which is beneficial to improving the performance and quality of the battery, as well as the reliability of lithium replenishment.

[0044] For example, the lithium source 410 can be disposed inside the electrode assembly 3 and adjacent to the negative electrode sheet 330 of the electrode assembly 3. Compared with spraying or coating the negative electrode current collector with a lithium metal layer, the problem of material shedding from the negative electrode can be avoided.

[0045] Furthermore, such as Figure 2 as well as Figures 4-8 As shown, the insulating bracket 420 is located between the negative terminal sub-assembly 202 and the electrode assembly 3. Therefore, in addition to supporting the conductive component 430, the insulating bracket 420 can also push the conductive part towards the negative terminal sub-assembly 202 when the electrode assembly 3 expands, until the conductive component 430 and the negative terminal sub-assembly 202 make contact and conduction, preventing the electrode assembly 3 from short-circuiting due to conduction between the electrode assembly 3 and the conductive component 430.

[0046] For example, the insulating support 420 can be made of a columnar structure using materials with excellent insulation and stability, such as plastic. This design not only effectively resists the corrosion of the electrolyte, but also separates the lithium replenishment structure 4 from the electrode assembly 3, thereby preventing the lithium replenishment structure 4 from participating in the battery's electrical cycling process, preventing interference with the normal charging and discharging function of the battery, and ensuring the stability and reliability of battery operation.

[0047] Furthermore, such as Figures 2-8As shown, the conductive component 430 is electrically connected to the lithium source tab 411 extending from the lithium source 410, and is connected to the end of the insulating support 420 away from the electrode assembly 3. In this way, when the expanded electrode assembly 3 pushes the conductive component 430 to contact and conduct with the negative terminal assembly 202 through the insulating support 420, the negative terminal assembly 202 and the lithium source 410 can form an electrical connection, so that the lithium source 410 can replenish lithium at the negative electrode of the battery.

[0048] For example, the conductive component 430 can be connected to the end of the insulating support 420 away from the electrode assembly 3. This can improve the stability of the lithium replenishment structure 4 inside the battery and prevent the conductive component 430 from falling off from the cover assembly 2 in environments with significant vibration, thereby improving the battery's environmental adaptability. In addition, a gap can be reserved between the conductive component 430 and the negative terminal assembly 202 in the early stages of battery application to prevent premature contact and premature lithium replenishment of the lithium replenishment structure 4.

[0049] In some embodiments, the cover assembly 2 includes a cover body 210 and a lower plastic 220; a positive terminal component 201 and a negative terminal component 202 are disposed on the cover body 210; the lower plastic 220 is disposed in a first receiving cavity 101 and is located between the cover body 210 and the electrode assembly 3; a second receiving cavity 222 is formed on the side of the lower plastic 220 facing the electrode assembly 3 for accommodating an insulating support 420 and a conductive component 430.

[0050] Specifically, such as Figures 2-8 As shown, the cover body 210 of the cover plate assembly 2 is located above the housing 1, so that the cover body 210 and the lower plastic 220 can be stacked on each other, and the cover body 210 presses the lower plastic 220 against the opening of the first receiving cavity 101, thereby achieving sealing and protection of the first receiving cavity 101; in addition, the positive terminal component 201 and the negative terminal component 202 are both exposed on the upper surface of the cover body 210, that is, the cover body 210 provides the installation position so as to achieve electrical connection with electrical equipment through the positive terminal component 201 and the negative terminal component 202.

[0051] More specifically, such as Figures 2-8 As shown, the lower plastic 220 of the cover assembly 2 is located between the cover body 210 and the housing 1. The lower plastic 220 can isolate the lower surface of the cover body 210 from the housing 1 and seal the opening of the first receiving cavity 101. In addition, the bottom of the lower plastic 220 is recessed towards the cover body 210 to form a second receiving cavity 222. The second receiving cavity 222 can accommodate the insulating support 420 and conductive component 430 of the lithium replenishment structure 4, reduce the encroachment of the insulating support 420 and conductive component 430 on the internal space of the first receiving cavity 101, increase the proportion of the electrode assembly 3 in the first receiving cavity 101 and ensure the battery capacity.

[0052] For example, the cover 210 can be formed of aluminum and its alloys, which helps to control the weight of the battery and ensure its overall strength. Since the positive terminal component 201 and the negative terminal component 202 are exposed relative to the cover 210, in order to avoid direct contact between the two and the cover 210, an insulating plastic layer can be provided on the upper surface of the cover 210 to prevent the cover 210 from short-circuiting with at least one of the positive terminal component 201 and the negative terminal component 202.

[0053] In some embodiments, the battery further includes a first spring sheet 5, the two ends of which are fixed to the lower plastic 220 extending in a first direction and connected to the conductive component 430 and the lithium source tab 411, respectively.

[0054] Specifically, such as Figure 2 as well as Figures 4-8 As shown, the first spring piece 5 spans across the second receiving cavity 222 in the first direction, and its two ends are fixedly connected to the lower plastic 220 respectively. In this way, the first spring piece 5 can not only establish a reliable electrical connection with the conductive component 430, but also provide corresponding support for the conductive component 430 to prevent it from falling into the first receiving cavity 101 and short-circuiting with the electrode assembly 3, thereby ensuring the safety of the battery. More specifically, the lower surface of the first spring piece 5 can provide a larger connection area for the lithium source electrode tab 411, which can reduce the connection difficulty between the lithium source electrode tab 411 and the conductive component 430 and improve the assembly efficiency.

[0055] Furthermore, the first spring 5 is located between the positive terminal component 201 and the negative terminal component 202 in the second direction, and between the lower plastic 220 and the electrode component 3 in the third direction; the first direction, the second direction, and the third direction are the width direction, the length direction, and the thickness direction of the cover plate component 2, respectively.

[0056] Specifically, Figure 2 as well as Figures 4-8 As shown, when the first spring 5 is disposed between the positive terminal assembly 201 and the negative terminal assembly 202 in the second direction, and disposed between the lower plastic 220 and the electrode assembly 3 in the third direction, it can ensure that the first spring 5 establishes a good electrical connection with the conductive component 430 and the lithium source electrode 411 at the same time, and prevent the conductive component 430 or the lithium source electrode 411 from contacting the positive terminal assembly 201 and the negative terminal assembly 202 and interfering with the normal operation of the battery; more specifically, this design can improve the internal compactness of the battery internal structure, enhance the rationality of the utilization of the internal space of the casing 1, and reduce the waste of internal space.

[0057] Furthermore, since the two ends of the first spring sheet 5 are fixed to the peripheral wall of the second receiving cavity 222 and extend along the first direction, when the electrode assembly 3 expands, the first spring sheet 5 will generate an upward elastic deformation under pressure and effectively block the electrode assembly 3. This design allows the electrode assembly 3 to enter the second receiving cavity 222, thereby avoiding interference of the lithium replenishment structure 4 with the normal operation of the battery.

[0058] For example, for the cover plate assembly 2, its first direction, second direction and third direction can be the width direction, length direction and thickness direction of the cover plate assembly 2, respectively; for the sake of facilitating a detailed description of the battery structure, the first direction, second direction and third direction can be made to be perpendicular to each other, which will not be elaborated here.

[0059] In some embodiments, the negative terminal assembly 202 of the battery can be electrically connected to the electrode assembly 3 via the positive electrode tab 311 to form the negative electrode structure of the battery. The negative terminal assembly 202 includes a negative terminal 2021, which penetrates both the cover 210 and the lower plastic 220, and is electrically connected to the negative electrode tab 331 extending from the electrode assembly 3. Furthermore, there is a gap between the negative terminal 2021 and the first spring tab 5 in the second direction.

[0060] Specifically, such as Figures 5-7 As shown, the negative terminal assembly 202 may include a negative terminal 2021 that passes through the cover 210 and the lower plastic 220 in sequence, i.e., an integrated negative terminal 2021. This reduces the difficulty of installing the negative terminal assembly 202 on the cover assembly 2 during battery assembly. In addition, the gap between the negative terminal 2021 and the first spring 5 can be used to accommodate the conductive component 430.

[0061] As an alternative embodiment, the negative terminal assembly 202 further includes a negative terminal 2021 and a negative terminal adapter 2022. The negative terminal 2021 penetrates the cover 210 and the lower plastic 220 respectively. The negative terminal adapter 2022 is electrically connected to the side of the negative terminal 2021 near the electrode assembly 3, and there is a gap between the negative terminal adapter 2022 and the first spring 5 in the second direction.

[0062] Specifically, such as Figure 8As shown, the negative terminal assembly 202 may further include a negative terminal 2021 that passes through the cover 210 sequentially, and a negative electrode adapter 2022 connected to the end of the negative terminal 2021 near the electrode assembly 3. When the negative terminal assembly 202 is constructed using the negative terminal 2021 and the negative electrode adapter 2022, the negative electrode adapter 2022 can provide a larger connection area for the negative electrode tab 331 and the conductive component 430, ensuring a good connection between the negative electrode adapter 2022 and the negative electrode tab 331, and also ensuring that the electrode assembly 3 can be fully connected to the conductive component 430 after expansion. In addition, the gap between the negative terminal 2021 and the first spring 5 can be used to accommodate the conductive component 430.

[0063] For example, the negative terminal 2021 and the negative terminal adapter 2022 can be connected by welding, which will not be described in detail here.

[0064] In some embodiments, the battery further includes a second spring 6, which is located between the electrode assembly 3 and the insulating support 420 to support the insulating support 420. The two ends of the second spring 6 are fixed to the peripheral wall of the second receiving cavity 222 and extend along the first direction.

[0065] Specifically, such as Figure 2 as well as Figures 4-8 As shown, in the battery, the second spring 6 extends in the first direction and its two ends are fixed to the peripheral wall of the second receiving cavity 222. It is positioned between the electrode assembly 3 and the insulating support 420 in the third direction. This design allows the second spring 6 to provide stable support for the insulating support 420. When the electrode assembly 3 expands, it contacts the lower surface of the second spring 6 and causes the second spring 6 to produce uniform elastic deformation. This elastic deformation allows the second spring 6 to apply a balanced thrust to the insulating support 420, thereby ensuring that the movement trajectory of the insulating support 420 is stable and reliable, which is beneficial to improving the lithium replenishment effect of the lithium replenishment structure 4.

[0066] Furthermore, since the second spring 6 extends in the first direction and spans the second receiving cavity 222, when the two ends of the first spring 5 are fixed to the peripheral wall of the second receiving cavity 222 of the lower plastic 220, the expanding electrode assembly 3 can be blocked, preventing the electrode assembly 3 from intruding into the second receiving cavity 222.

[0067] In some embodiments, the conductive component 430 is a conductive connecting piece 431, one end of which is located between the negative terminal assembly 202 and the insulating support 420, and the other end is electrically connected to the lithium source electrode tab 411.

[0068] Specifically. For example... Figure 7As shown, the conductive component 430 may include a conductive connecting piece 431 located within the second receiving cavity 222. One end of the conductive connecting piece 431 is located between the negative terminal assembly 202 and the insulating support 420. When the electrode assembly 3 expands and applies pressure to the insulating support 420 through the second spring 6, the conductive connecting piece 431 can be pushed to bring the conductive connecting piece 431 and the negative terminal assembly 202 closer together and make contact. More specifically, since the other end of the conductive connecting piece 431 is electrically connected to the lithium source tab 411 extending from the lithium source 410, the negative terminal assembly 202 is made to be connected to the lithium source 410 through the conductive component 430, thereby ensuring the reliability of the connection between the lithium replenishment structure 4 and the negative terminal assembly 202.

[0069] For example, one end of the conductive connecting piece 431 is connected to the end of the insulating support 420 away from the electrode assembly 3. This not only enhances the structural stability of the conductive connecting piece 431 in the second receiving cavity 222, but also ensures that the end of the conductive connecting piece 431 moves synchronously with the insulating support 420, thereby improving the coordination and reliability of the lithium replenishment structure 4.

[0070] For example, one end of the conductive connecting piece 431 can be disposed between the negative terminal component 202 and the insulating support 420, and the other end can be integrally connected to the first spring piece 5, so that at least a portion of the conductive connecting piece 431 overlaps the end of the insulating support 420; this not only reduces the assembly difficulty, but also improves the overall assembly efficiency of the battery.

[0071] As an alternative embodiment, the conductive component 430 includes a conductive connecting piece 431 and a metal spring piece 432. One end of the conductive connecting piece 431 is electrically connected to the lithium source electrode tab 411, and the other end is connected to the metal spring piece 432. The metal spring piece 432 is located between the negative terminal component 202 and the insulating support 420. Its two ends are fixed to the peripheral wall of the second receiving cavity 222 and extend along the first direction. When the electrode component 3 expands, it pushes the insulating support 420 to drive the metal spring piece 432 to switch from the first state to the second state. When the metal spring piece 432 is in the first state, there is a gap between it and the negative terminal component 202. When it is in the second state, it is in contact with the negative terminal component 202 and conducts electricity.

[0072] Specifically, such as Figure 2 , Figure 5 , Figure 8 as well as Figure 9As shown, the conductive component 430 may further include a conductive connecting piece 431 and a metal spring piece 432 located in the second receiving cavity 222; wherein, when the metal spring piece 432 is in the first state, there is a gap between the metal spring piece 432 and the negative terminal component 202, and at this time the lithium replenishment structure 4 is not connected to the negative terminal component 202, so it will not replenish lithium to the negative electrode; when the metal spring piece 432 is in the second state, the metal spring piece 432 is in contact with the negative terminal component 202, so that an electrical connection relationship is established between the metal spring piece 432, the conductive connecting piece 431, the lithium source tab 411 and the lithium source 410, and the lithium replenishment structure 4 is triggered to replenish lithium to the negative electrode of the battery.

[0073] More specifically, the metal spring 432 is located between the negative terminal assembly 202 and the insulating support 420. Its two ends are fixed to the lower plastic 220 in a first direction. When the electrode assembly 3 expands, the insulating support 420 can apply a pushing force to the metal spring 432. Because the metal spring 432 is elastic, its elasticity allows it to deform significantly towards the negative terminal assembly 202, causing it to abut against the lower surface of the negative terminal assembly 202. This allows the negative terminal assembly 202 to become conductive with the lithium source 410 when the metal spring 432 switches from the first state to the second state. Therefore, the metal spring 432 increases the reliability of the connection between the negative terminal assembly 202 and the conductive component 430, ensuring continuous conductivity between the negative terminal assembly 202 and the lithium source 410.

[0074] For example, the conductive connecting piece 431 and the metal spring piece 432 can be connected by an integral molding process to ensure that the conductive component 430 has good mechanical strength and conductive reliability.

[0075] For example, the conductive connecting piece 431 and the first spring piece 5 can be connected by a welding process, which can reduce the assembly difficulty between the conductive connecting piece 431 and the first spring piece 5.

[0076] In some embodiments, the electrode assembly 3 includes a positive electrode 310, a separator 320, and a negative electrode 330 stacked alternately in sequence. The separator 320 is used to isolate the positive electrode 310 and the negative electrode 330. The positive electrode 310, the negative electrode 330, and the separator 320 are wound to form a roll structure. The positive electrode 310 extends a positive electrode tab 311 and is electrically connected to the positive terminal assembly 201. The negative electrode 330 extends a negative electrode tab 331 and is electrically connected to the negative terminal assembly 202.

[0077] Specifically, such as Figures 10-12 As shown, Figure 10 This is a perspective view of electrode assembly 3 in an embodiment of this application. Figure 11 This is a schematic diagram of the composition of electrode assembly 3 in an embodiment of this application. Figure 12This is a schematic diagram showing the positional relationship between the lithium source 410 and the negative electrode 330 in an embodiment of this application. The positive electrode 310, the separator 320, and the negative electrode 330 can be wound into a roll structure using a winding process.

[0078] More specifically, for the electrode assembly 3, within the first receiving cavity 101, the positive electrode tab 311 extending from the positive electrode plate 310 toward the cover plate assembly 2 can be electrically connected to the positive terminal assembly 201, and the negative electrode tab 331 extending from the negative electrode plate 330 toward the cover plate assembly 2 can be electrically connected to the negative terminal assembly 202, thus forming the internal circuit structure of the battery. To prevent short circuits caused by contact between the positive electrode plate 310 and the negative electrode plate 330, a separator 320 is provided between adjacent positive electrode plates 310 and negative electrode plates 330 for isolation. This not only ensures the safety of the electrode assembly 3 but also ensures that lithium ions can move freely during charging and discharging, thereby completing the storage and release of electrical energy.

[0079] Furthermore, the lithium source 410 is located between the adjacent negative electrode 330 and the separator 320, and the lithium source tab 411 is located between the positive electrode tab 311 and the negative electrode tab 331; specifically, as shown... Figure 10 As shown, placing the lithium source 410 between the adjacent negative electrode 330 and the separator 320 along the first direction can increase the lithium ion concentration around the negative electrode 330, thereby improving the lithium replenishment effect on the negative electrode 330. In addition, since the positive electrode 310 and the lithium source 410 are blocked by the separator 320, the lithium replenishment structure 4 can be prevented from participating in the battery's electric cycle process, thus improving the battery's safety.

[0080] Similarly, such as Figure 10 As shown, the lithium source tab 411 is positioned between the positive tab 311 and the negative tab 331 along the second direction, which can maintain a certain distance between the negative tab 331, the negative terminal assembly 202, the positive tab 311 and the positive terminal assembly 201 and the lithium source tab 411, and prevent these components from contacting the lithium source tab 411 and affecting the battery's electric cycle function.

[0081] In some embodiments, the lithium source 410 is a lithium metal layer. Along the arrangement direction of the positive electrode 310, the separator 320, and the negative electrode 330, the lithium source 410 is located near the center of the electrode assembly 3 and is disposed between the negative electrode 330 and the separator 320.

[0082] Specifically, such as Figure 10 As shown, when the lithium source 410 adopts a metallic lithium layer, the contact area between the lithium source 410 and the negative electrode 330 can be increased, the uniformity of lithium ions around the negative electrode 330 can be improved, thereby improving the lithium replenishment effect on the negative electrode 330.

[0083] More specifically, such as Figure 10As shown, since the electrode assembly 3 has a wound structure, by placing the lithium source 410 between the negative electrode plate 330 and the separator 320 near the center of the electrode assembly 3, not only can the stability of the lithium source 410 installed in the electrode assembly 3 be enhanced, but the space in the center of the electrode assembly 3 can also be used reasonably, which is beneficial to controlling the overall volume of the electrode assembly 3.

[0084] For example, the lithium source 410 can be disposed between the innermost negative electrode 330 and the separator 320 in the central region of the electrode assembly 3, or it can be disposed between the second negative electrode 330 and the separator 320 in the central region of the electrode assembly 3, which will not be described in detail here.

[0085] As an alternative embodiment, the lithium source 410 is a lithium metal layer. Along the arrangement direction of the positive electrode 310, the separator 320, and the negative electrode 330, the lithium source 410 is far away from the center of the electrode assembly 3 and close to the housing 1, and is disposed between the negative electrode 330 and the separator 320.

[0086] Specifically, such as Figure 10 As shown, for electrode assembly 3, along the arrangement direction of positive electrode 310, separator 320 and negative electrode 330 in electrode assembly 3, the electrode located in the central region of electrode assembly 3 suffers relatively high lithium-ion loss during charging and discharging due to problems such as large bending stress and insufficient electrolyte wetting; the electrode in the edge region may have uneven electrolyte distribution, resulting in local lithium-ion transport obstruction and relatively high lithium-ion loss.

[0087] To improve the lithium replenishment effect of negative electrode plates 330 at different positions in electrode assembly 3, the lithium source 410 can be placed between adjacent negative electrode plates 330 and separator 320 near the housing 1, which can increase the lithium replenishment effect of negative electrode plates 330 at the edge of electrode assembly 3 and improve the lithium replenishment capacity of lithium replenishment structure 4.

[0088] For example, the lithium source 410 can be disposed between the outermost negative electrode 330 and the separator 320 in the edge region of the electrode assembly 3, or it can be disposed between the second negative electrode 330 and the separator 320 in the edge region of the electrode assembly 3, which will not be described in detail here.

[0089] In some embodiments, at least one side of the negative electrode 330 and the positive electrode 310 is covered with an active layer 340.

[0090] like Figure 11 and Figure 12As shown, the active layers 340 covering the surfaces of the negative electrode 330 and the positive electrode 310 are used for reversibly inserting and extracting lithium ions, respectively. For example, the active layer 340 on the surface of the positive electrode 310 can be made of a lithium compound, which can release lithium ions during charging and receive lithium ions during discharging. The active layer 340 on the surface of the negative electrode 330 receives lithium ions during charging and releases lithium ions during discharging. In this way, through the conversion between electrical energy and chemical energy, the battery can have the function of energy storage and power supply.

[0091] Furthermore, according to the arrangement direction of the positive electrode 310, the separator 320 and the negative electrode 330, the thickness ratio between the lithium source 410 and the active layer 340 is within the range of 20%-50%.

[0092] like Figure 11 and Figure 12 As shown, the lithium source 410 can be a metallic lithium layer embedded between the adjacent negative electrode 330 and the separator 320 to replenish the negative electrode of the battery through the deposition of lithium ions. The thickness ratio between the lithium source 410 and the active layer 340 is controlled within the range of 20%-50%. Specifically, setting the thickness ratio between the lithium source 410 and the active layer 340 to above 20% ensures sufficient lithium content inside the battery for continuous replenishment, thereby maintaining battery performance and extending its lifespan. Simultaneously, setting the thickness ratio between the lithium source 410 and the active layer 340 to below 50% controls the thickness of the lithium source 410, preventing an increase in the volume of the electrode assembly 3 due to increased lithium source 410, which would affect its normal assembly. This not only ensures the lithium replenishment effect of the battery but also maintains the overall compactness and efficiency of the electrode assembly 3.

[0093] In some embodiments, the height of the lithium source 410 in the thickness direction of the cover plate assembly 2 is less than the minimum height of the active layer 340.

[0094] Specifically, such as Figure 11 and Figure 12 As shown, since the lithium replenishment structure 4 does not participate in the charging and discharging process of the battery, in the thickness direction of the cover plate assembly 2, i.e., the third direction upward, by making the height of the lithium source 410 less than the minimum height of the active layer 340, the risk of short circuit caused by the top of the lithium source 410 contacting the positive electrode tab 311 and the negative electrode tab 331 can be avoided.

[0095] It should be noted that some embodiments of this application have been described above. Other embodiments are within the scope of the appended claims.

[0096] The various embodiments in this application are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0097] The description in this application is given for illustrative purposes and is not intended to be exhaustive or to limit the application to the forms disclosed. Many modifications and variations will be apparent to those skilled in the art. The embodiments were chosen and described to better illustrate the principles and practical application of this application and to enable those skilled in the art to understand this application and design various embodiments with various modifications suitable for a particular purpose.

[0098] Those skilled in the art should understand that the discussion of any of the above embodiments is merely exemplary and is not intended to imply that the scope of this application (including the claims) is limited to these examples; within the framework of this application, the technical features of the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations of different aspects of the embodiments of this application as described above, which are not provided in the details for the sake of brevity.

[0099] Although this application has been described in conjunction with specific embodiments thereof, many substitutions, modifications and variations of these embodiments will be apparent to those skilled in the art from the foregoing description.

[0100] The embodiments of this application are intended to cover all such substitutions, modifications, and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the embodiments of this application should be included within the protection scope of this application.

Claims

1. A single-cell battery, characterized in that, include: case; A cover plate assembly is connected to the housing and forms a first receiving cavity; the cover plate assembly is provided with a positive terminal component and a negative terminal component; The electrode assembly is electrically connected to the positive terminal assembly and the negative terminal assembly respectively within the first receiving cavity; A lithium replenishment structure, located within the first accommodating cavity, includes a lithium source, an insulating support, and a conductive component. The insulating support is located between the negative terminal assembly and the electrode assembly. The conductive component is electrically connected to a lithium source tab extending from the lithium source and is located between the insulating support and the negative terminal assembly. When the electrode assembly expands, it pushes the insulating bracket to cause the conductive component to make contact with the negative terminal assembly and conduct electricity.

2. The single-cell battery according to claim 1, characterized in that, The cover plate assembly includes: A cover body, wherein the positive terminal sub-assembly and the negative terminal sub-assembly are disposed on the cover body; A lower plastic is disposed in the first receiving cavity and located between the cover and the electrode assembly; a second receiving cavity for accommodating the insulating support and the conductive component is formed on the side of the lower plastic facing the electrode assembly.

3. The single-cell battery according to claim 2, characterized in that, Also includes: The first spring contact has two ends fixed to the peripheral wall of the second receiving cavity and extending along the first direction, and is respectively connected to the conductive component and the lithium source electrode tab. The first spring is located between the positive terminal sub-assembly and the negative terminal sub-assembly in the second direction, and between the lower plastic and the electrode assembly in the third direction; Wherein, the first direction, the second direction, and the third direction are respectively the width direction, the length direction, and the thickness direction of the cover plate assembly.

4. The single-cell battery according to claim 3, characterized in that, The negative terminal component includes: The negative terminal extends through the lower plastic and is electrically connected to the negative electrode tab extending from the electrode assembly, and there is a gap between the negative terminal and the first spring in the second direction; It may include a negative terminal and a negative electrode adapter, the negative terminal penetrating the lower plastic, the negative electrode adapter being connected to the side of the negative terminal near the electrode assembly, and the negative electrode adapter and the first spring sheet having a gap in the second direction.

5. The single-cell battery according to claim 3, characterized in that, Also includes: The second spring is located between the electrode assembly and the insulating support, and is used to support the insulating support. The two ends of the second spring are fixed to the peripheral wall of the second receiving cavity and extend along the first direction.

6. The single-cell battery according to claim 3, characterized in that, The conductive component is a conductive connecting piece, one end of which is located between the negative terminal assembly and the insulating support, and the other end is electrically connected to the lithium source electrode tab. When the electrode assembly expands, it pushes the insulating bracket to cause the conductive connecting piece to make contact with the negative terminal assembly and conduct electricity. It may include a conductive connecting piece and a metal spring, one end of the conductive connecting piece being connected to the lithium source electrode tab, and the other end being connected to the metal spring; the metal spring is located between the negative terminal assembly and the insulating support, with both ends fixed to the peripheral wall of the second receiving cavity and extending along the first direction. When the electrode assembly expands, it pushes the insulating bracket to switch the metal spring from a first state to a second state. When the metal spring is in the first state, there is a gap between it and the negative terminal assembly. When it is in the second state, it makes contact with the negative terminal assembly and conducts electricity.

7. The single-cell battery according to claim 1, characterized in that, The electrode assembly includes: A positive electrode, a separator, and a negative electrode are stacked alternately in sequence, with the separator separating the positive and negative electrode. The positive electrode, the negative electrode, and the diaphragm are wound together to form a roll structure. The positive electrode extends a positive electrode tab and is electrically connected to the positive terminal assembly. The negative electrode extends a negative electrode tab and is electrically connected to the negative terminal assembly. The lithium source is located between the adjacent negative electrode and the separator, and the lithium source tab is located between the positive electrode tab and the negative electrode tab.

8. The single-cell battery according to claim 7, characterized in that, The lithium source is a lithium metal layer. Along the arrangement direction of the positive electrode, the separator, and the negative electrode, the lithium source is located near the center of the electrode assembly and is disposed between the negative electrode and the separator; And / or, along the arrangement direction of the positive electrode, the separator, and the negative electrode, the lithium source is away from the center of the electrode assembly, close to the housing, and is disposed between the negative electrode and the separator.

9. The single-cell battery according to claim 7, characterized in that, At least one side of the negative electrode and the positive electrode is covered with an active layer; According to the arrangement direction of the positive electrode, the separator and the negative electrode, the thickness ratio between the lithium source and the active layer is within the range of 20%-50%.

10. The single-cell battery according to claim 9, characterized in that, The height of the lithium source in the thickness direction of the cover plate is less than the minimum height of the active layer.

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