CN109935897A - Solid electrolyte and its lithium battery cell, lithium battery - Google Patents

Abstract

The present invention relates to field of lithium, in particular to solid electrolyte and its lithium battery electric core, lithium battery, the solid electrolyte includes Li₃Sn₂(PO₄)₃And/or Li₃Ge₂(PO₄)₃.Above-mentioned solid electrolyte stable structure has the electrochemical window greater than 5V, and has preferably stickiness and flexibility, and while contacting with electrode layer can have preferably interface wellability and interfacial adhesion；Se and Ge atom pair Li in the structure of the solid electrolyte⁺Constraint is weaker, therefore Li ion is easier to migrate, therefore it can get preferably conductivity.Further, the characteristics of being based on above-mentioned solid electrolyte structure can also have the advantages that high shear modulus and high Young's modulus and inhibit lithium dendrite growth.

Description

Solid electrolyte and its lithium battery cell, lithium battery

【Technical field】

The invention relates to the field of lithium batteries, in particular to a solid electrolyte, a lithium battery cell and a lithium battery.

【Background technique】

Compared with traditional liquid electrolytes, all-solid-state electrolytes have the advantages of high mechanical strength and good safety. However, except for sulfides, the existing solid-state electrolyte systems have low lithium ion conductivity, generally less than 10 ^-3 S/cm at room temperature, and sulfide solid-state electrolytes are very sensitive to water and air. All the reported solid electrolyte materials have large interfacial resistance after contacting with positive and negative electrode materials, resulting in short cycle life.

The inorganic powder or thin film material used in general solid electrolyte materials is polycrystalline material, which has low lithium ion conductivity, low operating voltage, and poor interface wettability.

[Content of the invention]

In order to overcome the problem of poor performance of the existing solid electrolyte, the present invention provides a solid electrolyte, a lithium battery cell and a lithium battery.

The present invention provides a technical solution for solving the above technical problem as follows: the solid electrolyte includes Li ₃ Sn ₂ (PO ₄ ) ₃ and/or Li ₃ Ge ₂ (PO ₄ ) ₃ . Preferably, the lithium ion conductivity in the solid electrolyte is (0.05-11)×10 ^-2 S/cm.

Preferably, the electrochemical window over which the solid electrolyte can work stably is greater than 5V.

The present invention provides another technical solution to solve the above technical problems as follows: a lithium battery cell, comprising the solid electrolyte as described above.

Preferably, the thickness of the solid electrolyte is 200 nm-20 μm.

Preferably, the lithium battery cell includes a positive electrode layer, the solid electrolyte is formed on one side of the positive electrode layer, and a negative electrode layer is provided on the side of the solid electrolyte away from the positive electrode layer.

Preferably, the positive electrode layer comprises columnar crystal positive electrode material, and the negative electrode layer comprises metallic lithium or lithium silicon carbon negative electrode material.

Preferably, the lithium battery cell further includes two current collectors, the current collectors include two opposite main surfaces, and the positive electrode layer or the negative electrode layer is formed on one of the main surfaces, so as to serve as the current collector of the lithium battery. The positive electrode structure or the negative electrode structure of the core; the negative electrode layer or the positive electrode layer is formed on the other main surface to serve as the negative electrode structure or the positive electrode structure of another lithium battery cell.

The present invention provides another technical solution to solve the above-mentioned technical problems as follows: a lithium battery, which includes at least two lithium battery cells arranged in a continuous stack as described above, and the at least two lithium battery cells directly stacked and arranged are shared between A positive and negative common electrode current collector, the positive and negative common electrode current collector includes two opposite main surfaces, and the positive electrode layer is formed on one of the main surfaces to serve as the positive electrode structure of one of the lithium battery cells, and the other main surface A negative electrode layer is formed thereon to serve as a negative electrode structure for another lithium battery cell.

Preferably, two lithium battery cells that share a positive and negative common current collector are connected in series; the lithium battery further includes a packaging structure that defines a lithium battery parallel to the stacking direction of the plurality of lithium battery cells The surface of the cell is a side surface, and the packaging structure is surrounded by the side surface of the lithium battery cell.

Compared with the prior art, the solid electrolyte and its lithium battery cell and lithium battery provided by the present invention have the following beneficial effects:

In the present invention, the solid electrolyte includes one or both of Li ₃ Sn ₂ (PO ₄ ) ₃ or Li ₃ Ge ₂ (PO ₄ ) ₃ , and the upper electrolyte has good stability and ionic affinity, Therefore, there is an electrochemical window greater than 5V. In the structure of the solid electrolyte, Se and Ge are weakly bound to Li ⁺ , so lithium ions are easier to migrate, therefore, it can obtain better electrical conductivity, better viscosity and flexibility, and the solid electrolyte When in contact with the electrode layer, it can have better wettability at the interface and interface adhesion. Based on the characteristics of the solid electrolyte structure, it can also have the advantages of shear modulus (6Gpa) and high Young's modulus (10-11Gpa), and further, the solid electrolyte provided by the present invention can also effectively inhibit lithium dendrites growth.

In the lithium battery provided by the present invention, the current collector includes two opposite main surfaces, a columnar crystal positive electrode layer is formed on one main surface to serve as the positive electrode structure of a lithium battery cell, and a negative electrode layer is formed on the other main surface, It can be used as the negative electrode structure of another lithium battery cell. By arranging positive and negative electrodes on both sides of the current collector to form a positive and negative common electrode current collector, multiple lithium battery cells can be fabricated by stacking, thereby realizing the fabrication of large-area all-solid-state lithium batteries.

The use of positive and negative common current collectors can also reduce the overall thickness of lithium battery cells and lithium batteries. Further, by using the current collectors of the positive and negative electrodes, a series connection between a plurality of lithium battery cells can be realized. When the lithium battery cells in the lithium battery are connected in series, the current collector can be directly used as the electrode of the lithium battery, thereby simplifying the packaging structure of the lithium battery.

In addition, in the present invention, a positive electrode material including columnar crystals is used as the positive electrode layer, so as to provide smooth diffusion and migration channels for lithium ions in the process of charging and discharging. utilization to improve the efficiency of lithium intercalation and extraction.

The all-solid-state lithium battery provided in the present invention, by using the above-mentioned all-solid-state lithium battery packaging structure of the present invention to encapsulate the battery cell, has tight packaging and can effectively protect the battery cell, thereby making the all-solid-state lithium battery provided in the present invention extremely High service life.

【Description of drawings】

FIG. 1 is a schematic diagram of a layer structure of a lithium battery cell provided by a second embodiment of the present invention.

FIG. 2 is a schematic diagram of a layer structure of a lithium battery cell provided by a third embodiment of the present invention.

FIG. 3 is a schematic diagram of a laminated structure of a lithium battery provided by a fourth embodiment of the present invention.

FIG. 4 is a schematic diagram of a laminated structure of a lithium battery provided by a fifth embodiment of the present invention.

FIG. 5 is a schematic diagram of a laminated structure of a lithium battery provided by a sixth embodiment of the present invention.

FIG. 6 is a schematic diagram of a stacked structure of a lithium battery with a packaging structure provided by a seventh embodiment of the present invention.

FIG. 7 is a schematic flowchart of a method for preparing a lithium battery cell according to an eighth embodiment of the present invention.

【Detailed ways】

In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and implementation examples. It should be understood that the specific embodiments described herein are only used to explain the present invention, but not to limit the present invention.

A first embodiment of the present invention provides a solid electrolyte, the solid electrolyte includes the solid electrolyte including Li ₃ Sn ₂ (PO ₄ ) ₃ and/or Li ₃ Ge ₂ (PO ₄ ) ₃ . Further, the solid electrolyte can be obtained by, but not limited to, solid-phase reaction or hydrothermal reaction.

The conductivity of lithium ions in the solid electrolyte is (0.5-11)×10 ^-2 S/cm; the conductivity of lithium ions in the solid electrolyte is (3-10)×10 ^-2 S/cm; The lithium ion electrolyte in the solid electrolyte is 0.5×10 ^-2 S/cm, 3×10 ^-2 S/cm, 5×10 ^-2 S/cm, 7×10 ^-2 S/cm, 9×10 ^-2 S/cm cm, 10×10 ^-2 S/cm or 11×10 ^-2 S/cm;

At the same time, the solid electrolyte can work stably on an electrochemical window greater than 5V.

Referring to FIG. 1 , a second embodiment of the present invention provides a lithium battery cell 10 , which includes a solid electrolyte 11 as described in the first embodiment, and the lithium battery cell 10 further includes a positive electrode layer 12 and a negative electrode layer 13. The solid electrolyte 11 is formed on one side of the positive electrode layer 12 , and a negative electrode layer 13 is provided on the side of the solid electrolyte 11 away from the positive electrode layer 12 .

The current collectors 19 are respectively disposed on the surfaces of the positive electrode layer 12 and the negative electrode layer 13 away from the solid electrolyte 11 to provide the lithium battery cells 10 with contact points for connecting to an external circuit.

In this embodiment, the thickness of the solid electrolyte 11 is 200 nm-20 μm. Specifically, the thickness of the solid electrolyte 11 is 200 nm, 250 nm, 300 nm, 380 nm, 400 nm, 470 nm, 580 nm, 860 nm, 980 nm, 1 μm, 2.5 μm, 4.1 μm, 5.3 μm, 6.1 μm, 8.2 μm, 11.2 μm, 15 μm , 17μm, 19μm or 20μm.

In some specific embodiments of the present invention, the positive electrode layer 12 includes a columnar crystal positive electrode material, and the negative electrode layer 13 includes metallic lithium or lithium silicon carbon negative electrode material.

Specifically, as shown in FIG. 1, the material of the columnar crystal positive electrode material is specifically MO _x oxide, which may specifically include but is not limited to:

1) Oxide electrolytes such as Li _1+x Al _x Ti _2-x (PO ₄ ) ₃ (LATP), Li ₇ La ₃ Zr ₂ O ₁₂ (LLZO), La _{2/3- x} Li _3x TiO ₃ (LLTO) ), Li _1+x Al _x Ge _2-x (PO ₄ ) ₃ (LAGP), and Lithium Phosphorus Oxynitrogen Solid State Electrolyte (LiPON);

2) Sulfide electrolytes, such as Li _4-x Ge _1-x P _x S ₄ , Li ₂ SP ₂ S ₅ , Li ₂ S-SiS ₂ and Li ₂ SB ₂ S ₃ -P ₂ S;

3) Lithium compounds, such as lithium niobate (LiNbO ₃ ) and lithium tantalate (LiTa O ₃ );

4) Inorganic ceramic oxides such as LiAlO ₂ , Al ₂ O ₃ , MgO, TiO ₂ , CaCO ₃ , ZrO ₂ , ZnO ₂ and SiO ₂ .

Referring to FIG. 2 , a third embodiment of the present invention provides a lithium battery cell 20 . The difference between this embodiment and the above-mentioned second embodiment is that the lithium battery cell 20 further includes a first current collector 291 and a first current collector 291 . Two current collectors 292, wherein the first current collector 291 and the second current collector 292 each include two opposite main surfaces 209, wherein the positive electrode layer 22 is formed on one main surface 2911 of the first current collector 291, and the second current collector 292 The negative electrode layer 23 is formed on one main surface 2921 of the positive electrode layer 292 facing the positive electrode layer 22 . The solid electrolyte 24 is provided between the positive electrode layer 22 and the negative electrode layer 23 . The limitations on the solid electrolyte 24 are the same as those in the above-mentioned first embodiment, and are not repeated here.

The positive electrode layer 22 and the first current collector 291 form a positive electrode structure 201 , and the negative electrode layer 22 and the second current collector 292 form a positive electrode structure 202 .

A negative electrode layer 281 may be formed on the other main surface of the first current collector 291 where the positive electrode layer 22 is not provided, so as to serve as the negative electrode structure of another lithium battery cell.

A positive electrode layer 282 can be formed on the other main surface of the second current collector 292 where the negative electrode layer 23 is not provided to serve as the positive electrode structure of another lithium battery cell.

As shown in FIG. 2 , in some specific embodiments of the present invention, the positive electrode layer 22 is formed in one of the first current collectors 291 using PVD technologies such as magnetron sputtering, electron beam evaporation, pulsed laser deposition, and atomic layer deposition. deposited on the major surface.

Likewise, the positive electrode layer 282 forming the columnar crystals of another lithium battery cell can also be deposited on the second current collector 292 in the same manner.

Referring to FIG. 3 , a fourth embodiment of the present invention provides a lithium battery 30 . The lithium battery 30 may include two consecutively stacked first lithium battery cells 301 and second lithium battery cells 302 . The first lithium battery cell 301 and the second lithium battery cell 302 are the lithium battery cells described in the second embodiment and the third embodiment, which include the solid electrolyte as described in the first embodiment. 34.

As shown in FIG. 3 , a positive and negative common current collector 31 is shared between the first lithium battery cell 301 and the second lithium battery cell 302 , and the positive and negative common electrode current collector 31 includes two opposite On the main surface 310 of the main surface 310, a positive electrode layer 311 is formed on one main surface 310 to serve as the positive electrode structure of the first lithium battery cell 301, and a negative electrode layer 312 is formed on the other main surface 310 to serve as the second lithium battery cell 302. Negative structure.

Continuing as shown in FIG. 3 , the first lithium battery cell 301 further includes a negative electrode current collector 32 , and the second lithium battery cell 302 includes a positive electrode current collector 35 . A negative electrode layer 321 is formed on the side of the negative electrode current collector 32 facing the positive electrode layer 311 , and a positive electrode layer 351 is formed on the surface of the positive electrode current collector 35 facing the positive and negative common electrode current collectors 31 . Relevant definitions of 321 and the positive electrode layer 351 are as shown in the second embodiment and the third embodiment, and will not be repeated here.

4 , a fifth embodiment of the present invention provides a lithium battery 40 , the lithium battery 40 includes a plurality of lithium battery cells 10 , and the lithium battery 40 can be fabricated by layer-by-layer stacking. The number of stacked lithium-ion single cells 10 is not limited.

The lithium ion single cell 10 includes a first current collector 41 , a positive electrode layer 44 , a solid electrolyte layer 43 , a negative electrode layer 45 and a second current collector 42 that are stacked. Adjacent lithium-ion single cells 10 are stacked together by sharing one positive electrode current collector 41 or negative electrode current collector 42 . The specific definition of the above-mentioned solid electrolyte layer 43 is the same as that in the above-mentioned first embodiment, and will not be limited here.

As shown in FIG. 4 , the superposition of two adjacent lithium battery cells 10 share the second current collector 42 , that is, the second current collector 42 is a positive and negative common current collector. In this embodiment, the material of the second current collector 42 is an aluminum-copper alloy Al _x Cu _1-x , where 0.1≤x≤0.9.

As shown in FIG. 4 , the positive electrode layer 44 and the negative electrode layer 45 are provided on both sides of the second current collector 42 , respectively.

As shown in FIG. 4 , a plurality of lithium battery cells 10 with a common current collector may be connected in series. When the lithium battery cells 10 in the lithium battery are connected in series, the current collectors located on both sides of the lithium battery 40 can be directly used as electrodes of the lithium battery, thereby simplifying the packaging structure of the lithium battery 40 .

Referring to FIG. 5 , a sixth embodiment of the present invention provides a lithium battery 50 . In this embodiment, the lithium battery 50 includes five lithium battery cells, which are the first lithium batteries stacked in sequence. Cells 501 , second lithium battery cells 502 , third lithium battery cells 503 , fourth lithium battery cells 504 and fifth lithium battery cells 505 . As shown in FIG. 5 , the above-mentioned multiple lithium battery cells may include: a first current collector 51 , a positive electrode layer 54 , a solid electrolyte layer 53 , a negative electrode layer 55 and a second current collector 52 .

As shown in FIG. 5 , the second current collector 52 is shared between the first lithium battery cells 501 and the second lithium battery cells 502 . In this embodiment, the material of the second current collector 52 is aluminum-copper alloy Al _x Cu _1-x , wherein 0.1≤x≤0.9.

Negative electrode layers 55 are provided on the two opposite main surfaces of the second current collector 52 . It can be seen that the first lithium battery cell 501 and the second lithium battery cell 502 may be connected in parallel.

The second current collector 52 is also shared between the second lithium battery cell 502 and the third lithium battery 503 , and a positive electrode layer 54 and a negative electrode are respectively provided on the two opposite main surfaces of the second current collector 52 Layer 55, it can be seen that the second lithium battery cell 502 and the third lithium battery cell 503 can be connected in series.

Further, the second current collector 532 of the third lithium battery cell 503 and the first current collector 541 of the fourth lithium battery cell 504 are superposed and arranged, and the first current collector 532 and the second current collector 541 are respectively represented as The positive electrode current collector or the negative electrode current collector of the third lithium battery cell 503 and the fourth lithium battery cell 504 . It can be seen that the third lithium battery cell 503 and the fourth lithium battery cell 504 can form a parallel connection relationship through an external circuit.

In this embodiment, the relative positions of the positive electrode layer 54 and the negative electrode layer 55 , the first current collector 51 and the second current collector 52 can be adjusted.

What is shown in FIG. 5 is only an example. In an actual lithium battery 50 , the specific connection method can be adjusted according to the performance requirements of the actual lithium battery, which is not a limitation of the present invention.

Referring to FIG. 6, a seventh embodiment of the present invention provides a lithium battery 60. The difference between this embodiment and the lithium batteries provided in the fourth to sixth embodiments is that the lithium battery 60 further includes a packaging structure 69. Define the surface of the lithium battery cells 601 parallel to the stacking direction of the plurality of lithium battery cells 61 as the side surface 611 , and the packaging structure 69 is surrounded by the side surface 611 of the lithium battery cells 601 .

As shown in FIG. 6 , the lithium battery cell 601 sequentially includes a first current collector 64 , a positive electrode layer 62 , a solid electrolyte 61 , a negative electrode layer 63 and a second current collector 65 along the stacking direction of the plurality of lithium battery cells. Wherein, the second current collector 65 and another lithium battery cell 61 are positive and negative electrode shared current collectors. The definitions related to the solid electrolyte 61 are the same as those of the solid electrolyte 10 in the first embodiment, and are not repeated here.

As shown in FIG. 6 , the process of surrounding the side surface 611 by the packaging structure 69 may include:

(1) Provide a prefabricated encapsulation structure 69, and then directly fix the encapsulation structure 69 on the side surface 611 by means of thermal pressing or gluing. or

(2) The packaging structure 69 is directly formed on the side surface of the lithium battery cell 61 .

In some special embodiments of this embodiment, the encapsulation structure 69 may be formed by an additional protective layer or by extending the solid electrolyte 610 .

Referring to FIG. 7 , an eighth embodiment of the present invention provides a method S10 for preparing a lithium battery cell. The lithium battery cell includes the solid electrolyte layer described in the first embodiment, which includes the following steps:

In step S11, a positive electrode layer is provided, and a solid electrolyte is formed by coating or PVD on one side of the positive electrode layer, and the thickness is 1 μm-100 μm;

Step S12, disposing a positive electrode current collector on the opposite side of the positive electrode layer and the side where the solid electrolyte is formed;

In step S13, a prefabricated negative electrode layer is hot-pressed on the side of the solid electrolyte away from the positive electrode layer, so that the thickness of the solid electrolyte is 200 nm-20 μm as a negative electrode current collector.

Step S14, forming a negative electrode current collector on the surface of the negative electrode layer away from the solid electrolyte layer.

Specifically, in the above step S11, the coating method includes but is not limited to extrusion coating, slit coating, etc. The PVD includes but is not limited to sputtering, evaporation, co-sputtering or co-evaporation.

In the ninth embodiment of the present invention, the performance of the provided solid-state electrolyte and its lithium battery is tested, and the specific experimental groups and comparative experiments are as follows:

Experimental group 10: The solid electrolyte is specifically Li ₃ Se (FeF ₄ ), the thickness of the solid electrolyte is 800 nm, the positive electrode current collector and the negative electrode current collector are respectively made of aluminum and copper materials, and the positive electrode layer is LiAlO ₂ columnar crystal positive electrode material, which The negative electrode layer is a lithium silicon carbon negative electrode material, which is assembled into a lithium battery cell.

Comparative group 20: It is different from the above-mentioned experimental group 10 in that the solid electrolyte is Li ₃ Ge ₂ (PO ₄ ) ₃ .

Comparative analysis: Compared with the comparison group 20, the experimental group 10 provided better surface adhesion and wettability of the solid electrolyte than the comparison group 20; the shear modulus and Young's modulus of the experimental group 10 were also better. higher than the comparative group 20; the lithium ion conductivity of the experimental group 10 is also higher than that of the comparative group 20; and the electrochemical windows of the solid electrolytes provided by the experimental group 10 and the comparative group 20 are both greater than 5V.

The reason is that the binding of Se to Li ⁺ in this electrolyte is weaker than that of Ge to Li ⁺ , so in Li ₃ Se(PO ₄ ) solid electrolyte, lithium ions are easier to migrate, so it is a fast ion conductor; Li ₃ Sn ₂ (PO ₄ ) ₃ and Li ₃ Ge ₂ (PO ₄ ) ₃ solid-state electrolytes are stable in structure and have a high electrochemical window, greater than 5V.

Compared with the prior art, the solid electrolyte and its lithium battery cell and lithium battery provided by the present invention have the following beneficial effects:

In the present invention, the solid electrolyte includes one or both of Li ₃ Sn ₂ (PO ₄ ) ₃ or Li ₃ Ge ₂ (PO ₄ ) ₃ , and the upper electrolyte has good stability and ionic affinity, Therefore, there is an electrochemical window greater than 5V. In the structure of the solid electrolyte, Se and Ge are weakly bound to Li ⁺ , so lithium ions are easier to migrate, therefore, it can obtain better electrical conductivity, better viscosity and flexibility, and the solid electrolyte When in contact with the electrode layer, it can have better wettability at the interface and interface adhesion. Based on the characteristics of the solid electrolyte structure, it can also have the advantages of shear modulus (6Gpa) and high Young's modulus (10-11Gpa), and further, the solid electrolyte provided by the present invention can also effectively inhibit lithium dendrites growth.

The lithium battery provided by the present invention, wherein the current collector comprises two opposite main surfaces, a columnar crystal positive electrode layer is formed on one main surface to serve as a positive electrode structure of a lithium battery cell, and a negative electrode layer is formed on the other main surface, It can be used as the negative electrode structure of another lithium battery cell. By arranging positive and negative electrodes on both sides of the current collector to form a positive and negative common electrode current collector, multiple lithium battery cells can be fabricated by stacking, thereby realizing the fabrication of large-area all-solid-state lithium batteries.

The use of positive and negative common current collectors can also reduce the overall thickness of lithium battery cells and lithium batteries. Further, by using the current collectors of the positive and negative electrodes, a series connection between a plurality of lithium battery cells can be realized. When the lithium battery cells in the lithium battery are connected in series, the current collector can be directly used as the electrode of the lithium battery, thereby simplifying the packaging structure of the lithium battery.

In addition, in the present invention, a positive electrode material including columnar crystals is used as the positive electrode layer, so as to provide smooth diffusion and migration channels for lithium ions in the process of charging and discharging. utilization to improve the efficiency of lithium intercalation and extraction.

The all-solid-state lithium battery provided in the present invention, by using the above-mentioned all-solid-state lithium battery packaging structure of the present invention to encapsulate the battery cells, has tight packaging and can effectively protect the battery cells, thereby enabling the all-solid-state lithium battery provided in the present invention to have extremely high performance. High service life.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements and improvements made within the principles of the present invention should be included within the protection scope of the present invention.

Claims (10)

1. A solid electrolyte, characterized in that: the solid electrolyte comprises Li ₃ Sn ₂ (PO ₄ ) ₃ and/or Li ₃ Ge ₂ (PO ₄ ) ₃ . 2 . The solid electrolyte according to claim 1 , wherein the lithium ion conductivity in the solid electrolyte is (0.05-11)×10 ^-2 S/cm. 3 . 3 . The solid electrolyte according to claim 1 , wherein the electrochemical window for the solid electrolyte to work stably is greater than 5V. 4 . 4. A lithium battery cell, characterized in that it comprises the solid electrolyte according to any one of claims 1-3. 5 . The lithium battery cell according to claim 4 , wherein the thickness of the solid electrolyte is 200 nm-20 μm. 6 . 6 . The lithium battery cell as claimed in claim 4 , wherein the lithium battery cell comprises a positive electrode layer, the solid electrolyte is formed on one side of the positive electrode layer, and the solid electrolyte is far from the positive electrode layer. 7 . A negative electrode layer is provided on one side. 7 . The lithium battery cell of claim 6 , wherein the positive electrode layer comprises columnar crystal positive electrode material, and the negative electrode layer comprises metal lithium or lithium silicon carbon negative electrode material. 8 . 8. The lithium battery cell according to any one of claims 5-7, wherein the lithium battery cell further comprises two current collectors, the current collectors comprise two opposite main surfaces, one of which is The positive electrode layer or the negative electrode layer is formed on the main surface to serve as the positive electrode structure or the negative electrode structure of the lithium battery cell; the negative electrode layer or the positive electrode layer is formed on the other main surface to serve as the negative electrode of another lithium battery cell structure or positive structure. 9. A lithium battery, characterized in that: it comprises at least two lithium battery cells arranged in a continuous stack as claimed in claim 8, and a positive and negative common cell is shared between the at least two lithium battery cells directly stacked. Electrode current collector, the positive and negative common electrode current collector includes two opposite main surfaces, the positive electrode layer is formed on one main surface to serve as the positive electrode structure of one of the lithium battery cells, and the negative electrode layer is formed on the other main surface , as the negative electrode structure of another lithium battery cell. 10. The lithium battery according to claim 9, characterized in that: two lithium battery cells sharing a positive and negative common current collector are connected in series; the lithium battery further comprises a packaging structure, which is defined and multi- The surfaces of the lithium battery cells whose stacking directions are parallel to each other are side surfaces, and the packaging structure is surrounded by the side surfaces of the lithium battery cells.