Battery cell and lithium battery

Abstract

This application discloses a battery cell and a lithium battery. The battery cell is cylindrical and includes a positive electrode, a negative electrode, and a lithium replenishment component arranged radially along the cell. An insulating membrane is disposed between the positive and negative electrode to separate them. The insulating membrane allows ions to pass through while blocking electrons. The lithium replenishment component includes a lithium replenishment layer and a first insulating layer covering the outer surface of the lithium replenishment layer. The lithium replenishment layer is electrically connected to the negative electrode through a conductive wire. The first insulating layer allows ions to pass through while blocking electrons. Lithium can be replenished to the negative electrode through the lithium replenishment layer, thereby enhancing the energy density of the lithium battery.

Description

Technical Field

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

[0002] With the rapid development of the new energy industry, the market is placing higher demands on the performance of lithium batteries, with the most urgent need being to improve battery energy density. Among related technologies, energy density can be improved by optimizing the battery structure, and also by iterating on the positive and negative electrode materials to significantly enhance battery energy density.

[0003] However, during the use of lithium batteries, the active lithium in the positive electrode of the lithium battery will be irreversibly consumed, which will reduce the energy density of the lithium battery. Utility Model Content

[0004] This application provides a battery cell and a lithium battery that can replenish lithium to the negative electrode, thereby enhancing the energy density of the lithium battery.

[0005] In a first aspect, this application provides a battery cell that is cylindrical in shape. The battery cell includes a positive electrode, a negative electrode, and a lithium replenishment device arranged radially along the battery cell. An insulating membrane is disposed between the positive electrode and the negative electrode. The insulating membrane is used to separate the positive electrode and the negative electrode. The insulating membrane allows ions to pass through and can block electrons. The lithium replenishment component includes a lithium replenishment layer and a first insulating layer covering the outer surface of the lithium replenishment layer. The lithium replenishment layer is electrically connected to the negative electrode through a conductive wire. The first insulating layer allows ions to pass through and can block electrons.

[0006] Secondly, this application also provides a lithium battery, including a casing, a cap, and a cell. The cap is disposed at the positive terminal of the casing, the cell is located inside the casing, the positive electrode is electrically connected to the cap, and the negative electrode is electrically connected to the casing.

[0007] The beneficial effects of this application are as follows: On the one hand, the lithium replenishment layer is directly conductively connected to the negative electrode through conductive wires, allowing the lithium replenishment layer, the negative electrode, and the external power supply to form a lithium replenishment circuit. When the lithium replenishment circuit is energized, the lithium in the lithium replenishment layer loses electrons to form lithium ions, which gradually dissolve into the electrolyte, thus achieving lithium replenishment at the negative electrode. On the other hand, a lithium replenishment component separate from the negative electrode is used to achieve lithium replenishment at the negative electrode. The lithium replenishment layer in the component can be a large-volume lithium block, further encased in a first insulating layer. The larger volume of the lithium replenishment layer provides better stability in air and enhanced safety. Furthermore, the first insulating layer provides a certain degree of air isolation, reducing the probability of the lithium replenishment layer reacting with oxygen and other substances in the air, leading to a fire. In addition, the lithium replenishment layer is directly conductively connected to the negative electrode through conductive wires, eliminating the need for a third electrode and the discharge process between the third electrode and the negative electrode before normal lithium battery formation. This allows for direct normal lithium battery formation, simplifying the operation and the lithium battery manufacturing process. On the other hand, by distributing the positive electrode, negative electrode, and lithium replenishment components along the radial direction of the cell, the lithium replenishment components can be accommodated using the space inherent in the cell without changing the overall structure of the cell, without altering the shape of the cell or increasing its volume. Attached Figure Description

[0008] To more clearly illustrate the technical solutions in the embodiments or related technologies of this application, the drawings used in the description of the embodiments or related technologies 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.

[0009] Figure 1 This is a schematic diagram of the battery cell structure in one embodiment of this application; Figure 2 This is an exploded view of the components of a battery cell in one embodiment of this application; Figure 3 This is a partial structural diagram of a battery cell in one embodiment of this application.

[0010] Figure label: 10. Positive electrode sheet; 20. Negative electrode sheet; 30. Lithium replenishment component; 31. Lithium replenishment layer; 32. First insulating layer; 33. Second insulating layer; 40. Insulating membrane; 50. Conductive wire. Detailed Implementation

[0011] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0012] With the rapid development of the new energy industry, the market is placing higher demands on the performance of lithium batteries, with the most urgent need being to improve battery energy density. Among related technologies, energy density can be improved by optimizing the battery structure, such as through CTP (Cell To Pack) technology, CTC (Cell to Chassis) technology, and CTB (Cell to Body) technology. On the other hand, battery energy density can be significantly improved through the iteration of positive and negative electrode materials. For example, using high-nickel ternary or high-voltage nickel-manganese materials for the positive electrode and high-capacity silicon or tin-based alloy negative electrodes can achieve a substantial increase in battery energy density.

[0013] However, during the initial charge and discharge of a lithium battery, the electrolyte undergoes reducing decomposition on the negative electrode surface to form a solid electrolyte film, creating a solid electrolyte interphase (SEI) film. The SEI film prevents direct contact between the active electrode and the electrolyte, thus improving the cycle life of the lithium battery. However, the formation of the SEI film consumes active lithium extracted from the positive electrode, permanently depleting a large amount of active lithium from the positive electrode. Furthermore, processes such as the deactivation of negative electrode material particles due to detachment and irreversible lithium metal deposition also consume active lithium from the positive electrode. Therefore, during the use of the lithium battery, the active lithium in the positive electrode is irreversibly consumed, reducing the battery's capacity and energy density.

[0014] Therefore, related technologies propose using lithium replenishment technology to improve the energy density of lithium batteries. Lithium replenishment technology involves adding lithium to the lithium battery before it operates to replenish lithium ions, offsetting irreversible lithium loss and thus increasing the battery's total capacity and energy density. The lithium replenishment methods in related technologies typically fall into two categories: The first method of lithium replenishment involves coating the negative electrode with negative electrode material, and then spraying or evaporating a layer of lithium powder onto the negative electrode. The smaller lithium powder particles are more active and pose a risk of combustion and explosion when exposed to air. Furthermore, after lithium replenishment is performed on the negative electrode, the lithium powder on the negative electrode is prone to react with oxygen and other substances in the air, causing the lithium powder on the negative electrode to become deactivated and affecting the lithium replenishment effect.

[0015] The second method of lithium replenishment involves adding lithium metal to the lithium battery. This requires connecting the lithium metal to a specific battery casing or other structure, using the battery casing or other structure as a third electrode. The third electrode is then used to form a counter electrode with the positive or negative electrode for charging and discharging operations. This charging and discharging process pre-replenishes lithium to the negative electrode before the lithium battery undergoes normal formation. This method requires adding a third electrode and an additional discharge process between the third electrode and the negative electrode before the lithium battery is normalized, making the lithium battery manufacturing process more complicated.

[0016] In view of the above problems, this application provides a battery cell and a lithium battery to solve the above problems.

[0017] Firstly, this application provides a battery cell, such as Figures 1 to 3 As shown, the battery cell is cylindrical in shape and includes a positive electrode 10, a negative electrode 20, and a lithium replenishment component 30 arranged radially along the battery cell. An insulating membrane 40 is provided between the positive electrode 10 and the negative electrode 20. The insulating membrane 40 is used to separate the positive electrode 10 and the negative electrode 20. The insulating membrane 40 allows ions to pass through and can block electrons.

[0018] It is understood that the insulating membrane 40 is an insulating porous structure. The insulating membrane 40 can achieve physical isolation between the positive electrode 10 and the negative electrode 20, and also serve as an electronic isolation mechanism. The insulating membrane 40 effectively prevents physical contact between the positive electrode 10 and the negative electrode 20, as well as electron transport between them, thus preventing direct contact and short circuits. Simultaneously, the micropores on the insulating membrane 40 can provide ion channels between the positive electrode 10 and the negative electrode 20, allowing lithium ions in the electrolyte of the lithium battery to be transported through the micropores, thereby achieving ion exchange between the positive electrode 10 and the negative electrode 20. The specific working principle of the insulating membrane 40 has been disclosed in related technologies and will not be elaborated upon here. The materials used to prepare the insulating membrane 40 include, but are not limited to, polyethylene, polypropylene, glass fiber, ceramic-coated polyethylene, or ceramic-coated polypropylene.

[0019] Specifically, the lithium replenishment component 30 includes a lithium replenishment layer 31 and a first insulating isolation layer 32 covering the outer surface of the lithium replenishment layer 31. The lithium replenishment layer 31 is electrically connected to the negative electrode 20 through a conductive wire 50. The first insulating isolation layer 32 allows ions to pass through and can block electrons. It can be understood that the lithium replenishment layer 31 is made of lithium, and the first insulating isolation layer 32 wraps around the lithium replenishment layer 31. The first insulating isolation layer 32 is also a porous structure. The first insulating isolation layer 32 can play a similar role to the insulating membrane 40. The first insulating isolation layer 32 can achieve physical isolation between the lithium replenishment layer 31 and the positive electrode 10 and the negative electrode 20, and can also play a role in electronic isolation. At the same time, the micropores on the first insulating isolation layer 32 can also provide ion channels between the lithium replenishment layer 31 and the negative electrode 20, so that lithium ions formed after losing electrons in the lithium replenishment layer 31 can be transported through the micropores, thereby realizing lithium replenishment at the negative electrode.

[0020] It should be noted that the lithium replenishment layer 31 is directly conductively connected to the negative electrode 20 via the conductive wire 50, allowing the lithium replenishment layer 31, the negative electrode 20, and the external power source to form a lithium replenishment circuit. Before the lithium battery is formed, the cell can be immersed in the electrolyte of the lithium battery, and the negative electrode of the external power source can be conductively connected to the lithium replenishment layer 31, making the lithium replenishment layer 31 the negative electrode. The positive electrode of the external power source can be conductively connected to the negative electrode 20, making the negative electrode 20 the positive electrode, thus forming a lithium replenishment circuit. This allows the lithium in the lithium replenishment layer 31 to lose electrons and form lithium ions, which gradually dissolve into the electrolyte, thereby achieving negative electrode lithium replenishment. Alternatively, during the cell formation, the lithium on the lithium replenishment layer 31 can be used to form a solid electrolyte interphase (SEI) film on the surface of the negative electrode 20, which can significantly improve the capacity, energy density, first-cycle coulombic efficiency, and cycle life of the lithium battery. Furthermore, by controlling the magnitude of the charging and discharging current, the amount of lithium replenished in a single cycle can be controlled. All the lithium in the lithium replenishment layer 31 can be added to the lithium battery during the first formation cycle, thereby significantly improving the first-cycle coulombic efficiency of the battery. Alternatively, by controlling the magnitude of the charging and discharging current, lithium can be continuously replenished during subsequent charging and discharging processes, thereby improving the battery's cycle life. This can achieve the effects of improving the energy density, first-cycle coulombic efficiency, capacity, and cycle life of the lithium battery.

[0021] It should also be noted that, compared to the related technologies that plate a layer of small-particle lithium powder on the negative electrode sheet, this application uses a lithium replenishment component 30 separately positioned from the negative electrode sheet 20 to achieve negative electrode lithium replenishment. The lithium replenishment layer 31 in the lithium replenishment component 30 can be made of a large-volume lithium block, which is then wrapped by a first insulating layer 32. The lithium replenishment layer 31 has a larger volume, better stability in air, and stronger safety. In addition, the first insulating layer 32 can play a certain role in air isolation, thereby reducing the probability of the lithium replenishment layer 31 reacting with oxygen and other substances in the air, leading to fire. Furthermore, the lithium replenishment layer 31 is directly conductively connected to the negative electrode sheet 20 through a conductive wire 50, eliminating the need for a third electrode. This eliminates the need for a discharge process between the third electrode and the negative electrode before normal lithium battery formation, allowing for direct normal lithium battery formation. The operation is simpler, making the lithium battery manufacturing process simpler. The conductive wire 50 can be a wire with enameled insulation to prevent the conductive wire 50 from short-circuiting with the positive electrode 10. One end of the conductive wire 50 can pass through the first insulating isolation layer 32 to contact and connect with the lithium replenishment layer 31 located in the first insulating isolation layer 32.

[0022] It should also be noted that in this application, the positive electrode 10, negative electrode 20 and lithium replenishment component 30 are distributed radially along the cell. This allows the lithium replenishment component 30 to be accommodated within the existing space of the cell without changing the overall structure of the cell (which is cylindrical in shape). This does not require changing the shape of the cell or increasing its volume.

[0023] In some embodiments, the materials used to prepare the positive electrode 10 include, but are not limited to, one or more of lithium iron phosphate, lithium cobalt oxide, lithium manganese oxide, lithium nickel oxide, lithium nickel manganese oxide, ternary materials of lithium nickel cobalt manganese oxide, ternary materials of lithium nickel cobalt aluminum oxide, lithium-rich manganese-based materials, elemental sulfur, and carbon-sulfur composites; the materials used to prepare the negative electrode 20 include, but are not limited to, one or more of artificial graphite, natural graphite, mesophase carbon materials, hard carbon, soft carbon, porous carbon, lithium titanate, silicon, silicon suboxide, silicon oxide, silicon-carbon composite materials, tin, tin suboxide, tin oxide, tin-carbon composite materials, alloy negative electrode materials, metal oxide negative electrode materials, metal foil current collectors, porous metal current collectors, carbon-based current collectors, and conductive polymer current collectors.

[0024] In some embodiments, the lithium replenishment component 30 is located in the central region of the battery cell, and the positive electrode 10 and negative electrode 20 are arranged around the periphery of the battery cell. It is understood that the positive electrode 10 and negative electrode 20 are both annular, and the central region of the battery cell is a hollow region formed by the positive electrode 10 and negative electrode 20. Installing the lithium replenishment component 30 in the central region of the battery cell avoids the lithium replenishment component 30 occupying the arrangement space of the positive electrode 10 and negative electrode 20, thus minimizing changes to the overall structure of the battery cell. Furthermore, since the lithium replenishment component 30 is located inside the positive electrode 10 and negative electrode 20, the lithium on the lithium replenishment component 30 can diffuse fully from the inside out. The lithium on the lithium replenishment component 30 diffuses from the lithium replenishment component 30 to its surroundings, making the diffusion of lithium on the lithium replenishment component 30 more uniform.

[0025] Furthermore, the lithium replenishment layer 31 is a solid rod. Compared with the sheet-shaped lithium replenishment sheet, the solid rod lithium replenishment layer 31 occupies a smaller volume and has less impact on the existing structure of the cell. Moreover, the solid rod lithium replenishment layer 31 can contain more lithium, which can replenish more lithium to the lithium battery and enhance the lithium replenishment effect of the lithium replenishment component 30.

[0026] Furthermore, the lithium replenishing component 30 is cylindrical in shape, and its axis coincides with the axis of the battery cell. This allows the distance between the lithium replenishing component 30 and the positive electrode 10 and the negative electrode 20 to be basically consistent in all directions parallel to the radial direction of the battery cell. This makes it possible for the lithium on the lithium replenishing component 30 to diffuse more evenly from the lithium replenishing component 30 to the surrounding area.

[0027] In some embodiments, the positive electrode 10 is located between the negative electrode 20 and the lithium replenishment element 30, which increases the distance between the negative electrode 20 and the lithium replenishment element 30. This increases the diffusion distance of lithium from the lithium replenishment element 30 to the negative electrode 20, allowing the lithium on the lithium replenishment element 30 to diffuse more fully and evenly when replenishing lithium for the negative electrode. This allows for lithium replenishment in various regions of the negative electrode 20 and the formation of a more uniform SEI film in various regions of the negative electrode 20.

[0028] Furthermore, the two ends of the conductive wire 50 are connected to the negative electrode 20 and the lithium replenishment layer 31, respectively, and the conductive wire 50 is located on one side of the positive electrode 10 along the axial direction of the cell, so that the conductive wire 50 crosses the area where the positive electrode 10 is located from one side of the positive electrode 10 along the axial direction of the cell, thereby avoiding the positive electrode 10. When the conductive wire 50 connects the negative electrode 20 and the lithium replenishment layer 31, the conductive wire 50 can avoid the area where the positive electrode 10 is located, and the conductive wire 50 does not need to pass through the positive electrode 10, which can avoid the wire 50 passing through the positive electrode 10 and causing a hole in the positive electrode 10.

[0029] In some embodiments, along the radial direction of the cell, the lithium replenishment element 30, the positive electrode 10, and the negative electrode 20 are arranged sequentially. The positive electrode 10 is arranged around the periphery of the lithium replenishment element 30, and the negative electrode 20 is arranged around the periphery of the positive electrode 10, so that the negative electrode 20 is arranged further out. This makes the distance between the negative electrode 20 and the lithium battery casing closer when the cell is used in a lithium battery, making it easier to connect the negative electrode 20 to the lithium battery casing. Furthermore, the volume of the negative electrode 20 can be larger, allowing the negative electrode 20 to have more negative electrode material, thus meeting the design requirement of "excess negative electrode".

[0030] In other embodiments, the lithium replenishing element 30 may also be sheet-shaped, and the lithium replenishing element 30 may be located between the positive electrode sheet 10 and the negative electrode sheet 20, and may be arranged around the axis of the battery cell.

[0031] In some embodiments, an insulating membrane 40 may be provided on the outer side of the negative electrode 20. The insulating membrane 40 located on the outer side of the negative electrode 20 surrounds the negative electrode 20, which can achieve physical isolation between the negative electrode 20 and the lithium battery casing after the cell is applied to the lithium battery.

[0032] See also Figure 3 As shown, in some embodiments, the lithium replenishment component 30 further includes a second insulating isolation layer 33 disposed on the surface of the first insulating isolation layer 32. The second insulating isolation layer 33 allows ions to pass through and can block electrons. It can be understood that the second insulating isolation layer 33 encapsulates the first insulating isolation layer 32. The second insulating isolation layer 33 is also a porous structure. The second insulating isolation layer 33 can play a similar role to the first insulating isolation layer 32. The second insulating isolation layer 33 can also achieve physical isolation between the lithium replenishment layer 31 and the positive electrode 10 and the negative electrode 20, and can also play a role in electronic isolation. At the same time, the micropores on the second insulating isolation layer 33 can also provide ion channels between the lithium replenishment layer 31 and the negative electrode 20, so that lithium in the lithium replenishment layer 31 loses electrons and forms lithium ions that can be transported through the micropores, thereby realizing lithium replenishment at the negative electrode.

[0033] It should also be noted that, in this embodiment, by simultaneously providing the first insulating isolation layer 32 and the second insulating isolation layer 33, a double-layer insulating isolation function can be achieved, which can further improve the insulation performance of the lithium replenishment component 30. In addition, the second insulating isolation layer 33 can also play a certain role in air isolation, thereby further reducing the probability of the lithium replenishment layer 31 reacting with oxygen and other substances in the air and causing a fire.

[0034] In some embodiments, the porosity of the second insulating layer 33 is less than that of the first insulating layer 32. It is understood that porosity refers to the percentage of pore volume in a bulk object to the total volume of the object in its natural state; the higher the porosity, the less dense the object. The porosity of the first insulating layer 32 and the second insulating layer 33 directly affects the lithium ion migration efficiency between the lithium replenishment layer 31 and the electrolyte. Higher porosity in the first and second insulating layers 32 provides more lithium ion transport channels, thereby reducing the internal resistance of the lithium battery and improving charge / discharge efficiency; however, excessively high porosity may lead to excessive absorption of the electrolyte, which increases the risk of lithium battery swelling.

[0035] It should be noted that, in this embodiment, lithium ions generated by the lithium replenishment layer 31 need to pass through the first insulating isolation layer 32 and the second insulating isolation layer 33 sequentially before they can be transported to the negative electrode 20. The first insulating isolation layer 32 and the second insulating isolation layer 33 form a composite structure with a gradient change in porosity. The first insulating isolation layer 32 is located on the inner side, which makes the surface area of ​​the first insulating isolation layer 32 relatively small, but the porosity of the first insulating isolation layer 32 relatively large, so that the first insulating isolation layer 32 can provide sufficient lithium ion transport channels. The second insulating isolation layer 33 is located on the outer side. Although the porosity of the second insulating isolation layer 33 is relatively small, the surface area of ​​the second insulating isolation layer 33 is relatively large, so that the second insulating isolation layer 33 can also provide sufficient lithium ion transport channels, thereby ensuring the migration efficiency of lithium ions generated by the lithium replenishment layer 31. Furthermore, since the porosity of the second insulating isolation layer 33 is relatively small, the amount of electrolyte absorbed by the second insulating isolation layer 33 can be reduced, thereby preventing the electrolyte from being over-absorbed and increasing the risk of lithium battery swelling.

[0036] The porosity of the first insulating layer 32 and the second insulating layer 33 can be detected by the liquid absorption method. Taking the first insulating layer 32 as an example, the porosity of the first insulating layer 32 can be calculated by the volume of electrolyte or organic solvent absorbed by the first insulating layer 32.

[0037] In some embodiments, the porosity of the first insulating layer 32 is greater than or equal to 40%, and the porosity of the first insulating layer 32 can be 40%, 42%, 45%, or other values, so that the first insulating layer 32 can provide sufficient lithium-ion transport channels for lithium ions. The porosity of the second insulating layer 33 is less than or equal to 15%, and the porosity of the second insulating layer 33 can be 15%, 12%, 10%, or other values, to prevent the electrolyte from being excessively absorbed by the second insulating layer 33, which would increase the risk of lithium battery swelling.

[0038] In some embodiments, the first insulating layer 32 is a non-woven fabric insulating layer. Non-woven fabric has the characteristics of high porosity and large specific surface area. The non-woven fabric insulating layer formed by using non-woven fabric can meet the high porosity requirement of the first insulating layer 32. In addition, non-woven fabric has good flexibility and can play a good role in preventing puncture.

[0039] In some embodiments, the second insulating layer 33 is a lithium phosphorus oxynitride (LPN) solid electrolyte layer. LPN is an inorganic material with stable chemical and electrochemical properties. The LPN solid electrolyte layer can provide good physical and electronic isolation between the lithium replenishment layer 31 and the negative electrode 20 and the positive electrode 10. Furthermore, LPN can increase the reactivity of the lithium battery at low temperatures, thereby improving the low-temperature performance of the lithium battery. In addition, LPN contains lithium metal and can also be used as a lithium replenishment raw material, thereby further increasing the energy density, capacity and cycle life of the lithium battery.

[0040] Secondly, this application also provides a lithium battery, which includes a casing, a cap, and a cell as described in any of the above embodiments. The cap is disposed at the positive terminal of the casing, the cell is located inside the casing, the positive electrode 10 is electrically connected to the cap, and the negative electrode 20 is electrically connected to the casing.

[0041] The above are merely preferred embodiments of this application and are not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. An electric cell, which is cylindrical in its entirety, characterized in that, The battery cell includes a positive electrode, a negative electrode, and a lithium replenishment device arranged radially along the battery cell. An insulating membrane is disposed between the positive electrode and the negative electrode. The insulating membrane is used to separate the positive electrode and the negative electrode. The insulating membrane allows ions to pass through and can block electrons. The lithium replenishment component includes a lithium replenishment layer and a first insulating layer covering the outer surface of the lithium replenishment layer. The lithium replenishment layer is electrically connected to the negative electrode through a conductive wire. The first insulating layer allows ions to pass through and can block electrons.

2. The electric cell of claim 1, wherein, The lithium replenishment component is located in the central region of the battery cell, and the positive electrode and the negative electrode are arranged around the periphery of the lithium replenishment component.

3. The electric cell of claim 2, wherein, The lithium replenishment layer is a solid rod.

4. The battery cell according to claim 1, characterized in that, The positive electrode is located between the negative electrode and the lithium replenishment component.

5. The battery cell according to claim 4, characterized in that, The two ends of the conductive wire are respectively connected to the negative electrode and the lithium replenishment layer, and the conductive wire is located on one side of the positive electrode along the axial direction of the cell, so that the conductive wire crosses the area where the positive electrode is located from one side of the positive electrode along the axial direction of the cell, thereby allowing the conductive wire to avoid the positive electrode.

6. The battery cell according to claim 4, characterized in that, Along the radial direction of the battery cell, the lithium replenishing element, the positive electrode, and the negative electrode are arranged in sequence, with the positive electrode arranged around the periphery of the lithium replenishing element and the negative electrode arranged around the periphery of the positive electrode.

7. The battery cell according to claim 1, characterized in that, The lithium replenishment device further includes a second insulating layer disposed on the surface of the first insulating layer, the second insulating layer allowing ions to pass through and blocking electrons; The porosity of the second insulating layer is less than that of the first insulating layer.

8. The battery cell according to claim 7, characterized in that, The porosity of the first insulating layer is greater than or equal to 40%, and the porosity of the second insulating layer is less than or equal to 15%.

9. The battery cell according to claim 7, characterized in that, The first insulating layer is a non-woven fabric insulating layer; and / or, the second insulating layer is a lithium phosphorus oxygen nitrogen solid electrolyte layer.

10. A lithium battery, characterized in that, The device includes a housing, a cap, and a battery cell as described in any one of claims 1 to 9, wherein the cap is disposed at the positive terminal of the housing, the battery cell is located inside the housing, the positive electrode is electrically connected to the cap, and the negative electrode is electrically connected to the housing.

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