Lithium metal anode sheets and their preparation methods, secondary batteries and electrical devices

Abstract

This invention relates to a lithium metal anode sheet, its preparation method, a secondary battery, and an electrical device. The preparation method of the lithium metal anode sheet includes the following steps: mixing AgMF6 with an organic solvent to obtain a mixture, wherein M is selected from at least one of Ge, Si, Sb, As, or Al; forming the mixture on a lithium metal sheet and reacting it to obtain a lithium metal anode sheet, wherein the lithium metal anode sheet includes a lithium metal sheet and a protective layer formed on the surface of the lithium metal sheet. The preparation method of this invention can obtain a stable lithium metal anode sheet, which, when applied to a secondary battery, can effectively improve the electrochemical performance and safety performance of the secondary battery.

Description

Technical Field

[0001] This invention relates to the field of battery technology, and in particular to lithium metal anode sheets and their preparation methods, secondary batteries, and electrical devices. Background Technology

[0002] Lithium metal anodes are considered one of the most promising anode materials for next-generation high-energy-density energy storage systems due to their extremely high theoretical specific capacity. However, when lithium metal sheets are used as anodes in lithium-ion batteries, they are prone to dendrite formation during charging and discharging. The continuous growth of lithium dendrites can lead to short circuits in the battery, potentially causing thermal runaway and triggering risks such as fire and explosion.

[0003] In response, existing technologies disclose the use of antimony trifluoride to modify lithium metal anode sheets, causing a protective layer composed of lithium antimony alloy and lithium fluoride to be generated on the surface of the lithium metal anode sheet, which can suppress the formation of lithium dendrites. However, this protective layer has the following defects: (1) The chemical stability of lithium antimony alloy is relatively poor, especially in electrolyte, where it is prone to react with electrolyte; (2) When the battery is overcharged or over-discharged, lithium antimony alloy may undergo incomplete dealloying or uneven deposition, affecting battery performance; (3) Lithium antimony alloy may decompose or form unstable compounds at high temperatures, leading to a decrease in battery performance; (4) When the internal temperature of the battery rises, lithium antimony alloy may undergo chemical reactions, leading to thermal runaway or rupture of the battery. Summary of the Invention

[0004] Therefore, it is necessary to provide a lithium metal anode sheet and its preparation method, a secondary battery, and an electrical device to address the above problems. The preparation method described above can yield a stable lithium metal anode sheet, which can be effectively applied to secondary batteries to improve the electrochemical performance and safety performance of the secondary batteries.

[0005] A method for preparing a lithium metal anode sheet includes the following steps:

[0006] AgMF6 is mixed with an organic solvent to obtain a mixture, wherein M is selected from at least one of Ge, Si, Sb, As or Al;

[0007] The mixture is formed on a lithium metal sheet and reacted to obtain a lithium metal anode sheet, wherein the lithium metal anode sheet includes a lithium metal sheet and a protective layer formed on the surface of the lithium metal sheet.

[0008] In one embodiment, M is selected from Sb.

[0009] In one embodiment, the concentration of AgMF6 in the mixture is 1 mg / ml to 10 mg / ml.

[0010] In one embodiment, in the step of forming the mixture on a lithium metal sheet for reaction, the mass ratio of AgMF6 to the lithium metal sheet is 1:300-1:4000.

[0011] In one embodiment, the temperature is 40°C-80°C during the step of forming the mixture on a lithium metal sheet for reaction.

[0012] In one embodiment, the temperature during the step of mixing AgMF6 with the organic solvent is 25°C-40°C.

[0013] A lithium metal anode sheet obtained by the preparation method described above.

[0014] A secondary battery comprising the aforementioned lithium metal anode sheet.

[0015] In one embodiment, the secondary battery is a lithium-ion battery.

[0016] An electrical device that uses the aforementioned lithium-ion battery.

[0017] In the preparation method of the lithium metal anode sheet of this invention, AgMF6 can react with lithium metal sheet to generate LiF, elemental Ag, and elemental M in situ. First, LiF is an ideal component of the SEI film, while elemental Ag and elemental M can improve the electron transport efficiency between the SEI film composed of lithium metal sheet and LiF, optimize the uniformity of lithium deposition and stripping, and suppress the formation of lithium dendrites. Second, elemental Ag and elemental M can also enhance the mechanical strength of the protective layer, thereby improving the electrochemical performance of the secondary battery. Furthermore, there is a strong interaction between Ag and the selected M element in this invention, involving both metallic and covalent bonds. Therefore, when elemental Ag and elemental M are present simultaneously, they can undergo an alloying reaction to form an alloy. Moreover, silver can diffuse rapidly in the alloy, which is beneficial to improving the uniformity of the alloy. This alloy has a low enthalpy of formation and a small volume expansion, resulting in higher stability and less breakage. Therefore, the preparation method of this invention can obtain a stable lithium metal anode sheet, which can effectively improve the electrochemical and safety performance of secondary batteries when applied to them. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of this application or the conventional technology, the drawings used in the description of the embodiments or the conventional technology 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.

[0019] Figure 1These are optical photographs of the lithium metal sheet and the lithium metal anode sheet in Example 1, where a is an optical photograph of the lithium metal sheet and b is an optical photograph of the lithium metal anode sheet.

[0020] Figure 2 The image shows the XRD pattern of the protective layer on the surface of the lithium metal sheet obtained in Example 1. Detailed Implementation

[0021] To facilitate understanding of the present invention, it will be described in more detail below. However, it should be understood that the present invention can be implemented in many different forms and is not limited to the embodiments or examples described herein. Rather, these embodiments or examples are provided to make the disclosure of the present invention more thorough and complete.

[0022] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the specification of this invention is for the purpose of describing particular embodiments or examples only and is not intended to limit the invention. The optional scope of the term "and / or" as used herein includes any one of two or more of the related listed items, as well as any and all combinations of the related listed items, including any two related listed items, any more related listed items, or a combination of all related listed items.

[0023] In this invention, numerical ranges are involved. Unless otherwise specified, the numerical ranges are considered continuous and include the minimum and maximum values ​​of the range, as well as every value between the minimum and maximum values. Furthermore, when the range refers to integers, it includes every integer between the minimum and maximum values ​​of the range. Additionally, when multiple ranges are provided to describe features or characteristics, the ranges may be merged. In other words, unless otherwise specified, all ranges disclosed herein should be understood to include any and all subranges to which they are included.

[0024] The method for preparing a lithium metal anode sheet provided by the present invention includes the following steps:

[0025] S1, AgMF6 is mixed with an organic solvent to obtain a mixture, wherein M is selected from at least one of Ge, Si, Sb, As or Al;

[0026] S2, the mixture is formed on a lithium metal sheet and reacted to obtain a lithium metal anode sheet, wherein the lithium metal anode sheet includes a lithium metal sheet and a protective layer formed on the surface of the lithium metal sheet.

[0027] In the preparation method of this invention, the reaction equation between AgMF6 and lithium metal sheet is as follows:

[0028] 6Li + AgMF6 → 6LiF + Ag + M

[0029] As can be seen from the above reaction equation, when AgMF6 reacts with lithium metal sheet, LiF, elemental Ag, and elemental M are generated in situ, and these generated substances together form a protective layer.

[0030] First, LiF is an ideal component of SEI film, while AgMF6 mainly generates LiF when it reacts with lithium metal sheets. Therefore, the generated LiF can form SEI film. Elemental Ag and elemental M can improve the electron transport efficiency between the SEI film composed of lithium metal sheets and LiF, optimize the uniformity of lithium deposition and stripping, and suppress the formation of lithium dendrites.

[0031] Secondly, elemental Ag and elemental M can also enhance the mechanical strength of the protective layer, thereby improving the electrochemical performance of the secondary battery.

[0032] Furthermore, there is a strong interaction between Ag and M, the element selected in this invention, involving a mixture of metallic and covalent bonds. Therefore, when elemental Ag and elemental M coexist, they may undergo an alloying reaction to form an alloy. Moreover, silver can diffuse rapidly in the alloy, which is beneficial to improving the uniformity of the alloy. This alloy has a lower enthalpy of formation and a smaller volume expansion, resulting in higher stability and less brittleness.

[0033] Therefore, the preparation method of the present invention can yield a stable lithium metal anode sheet, which can be effectively applied to secondary batteries to improve the electrochemical performance and safety performance of secondary batteries.

[0034] It is understood that M in AgMF6 of the present invention can be selected from one of Ge, Si, Sb, As or Al, or from two or more of Ge, Si, Sb, As, and Al. When selected from two or more, such as Si and Sb, AgMF6 is AgSi. m Sb n F6, and m+n=1, preferably, M is selected from Sb, and AgMF6 is AgSbF6.

[0035] In step S1, the selection of the organic solvent for preparing the mixture by mixing AgMF6 with an organic solvent is not limited; commonly used organic solvents such as acetonitrile and N,N-dimethylformamide can be used. During mixing, the preferred temperature is 25℃-40℃, for example, 25℃, 30℃, 35℃, 40℃, or any combination of these values, which is beneficial for the dissolution and dispersion of AgMF6 in the organic solvent. Furthermore, the concentration of AgMF6 in the prepared mixture is preferably 1mg / ml-10mg / ml, for example, 1mg / ml, 2mg / ml, 3mg / ml, 4mg / ml, 5mg / ml, 6mg / ml, 7mg / ml, 8mg / ml, 9mg / ml, 10mg / ml, or any combination of these values.

[0036] In step S2, during the reaction of the mixture on a lithium metal sheet, the preferred mass ratio of AgMF6 to the lithium metal sheet is 1:300-1:4000, such as 1:300, 1:500, 1:800, 1:1000, 1:1500, 1:2000, 1:2500, 1:3000, 1:3500, 1:4000, or any combination of these values, such as between 1:800 and 1:1000, thereby allowing for the control of the protective layer thickness.

[0037] Furthermore, in the step of forming the mixture on a lithium metal sheet for reaction, the temperature is preferably 40℃-80℃, such as 40℃, 45℃, 50℃, 55℃, 60℃, 65℃, 70℃, 75℃, 80℃, or any combination of these values. This not only promotes the reaction but also facilitates the volatilization of the organic solvent.

[0038] Furthermore, the present invention also provides a lithium metal anode sheet obtained by the aforementioned preparation method. It is understood that the lithium metal anode sheet comprises a lithium metal sheet and a protective layer coating the surface of the lithium metal sheet. The protective layer comprises LiF, elemental Ag, elemental M, and an alloy formed from Ag and M, thereby giving the lithium metal anode sheet excellent stability.

[0039] The present invention also provides a secondary battery, including the lithium metal anode sheet, wherein the lithium metal anode sheet of the present invention has excellent stability, thereby effectively improving the electrochemical performance and safety performance of the secondary battery.

[0040] The secondary battery of the present invention can be a lithium-ion battery, a sodium-ion battery, an all-solid-state battery, etc., preferably a lithium-ion battery.

[0041] The present invention also provides an electrical device that uses the aforementioned lithium-ion battery. The electrical device can be an electronic device such as a mobile phone or laptop computer, or a new energy vehicle, etc.

[0042] The following specific embodiments will further illustrate the lithium metal anode sheet, its preparation method, the secondary battery, and the power-consuming device.

[0043] Example 1

[0044] First, weigh 100 mg of AgSbF6 powder into a glass bottle, add 10 ml of acetonitrile solution, and seal the bottle with sealing film. Then, place the bottle on a magnetic stirrer and stir for 5 hours, maintaining the temperature at 30°C, to obtain a homogeneous mixture.

[0045] Next, the mixed solution obtained above is uniformly dropped onto the surface of a lithium metal sheet, controlling the mass ratio of AgSbF6 to lithium metal sheet to be 1:300. Then, it is placed on a heating table at 40°C to dry, thus obtaining a lithium metal anode sheet.

[0046] Depend on Figure 1 It can be seen that after the lithium metal sheet reacts with AgSbF6, a protective layer is formed on the surface, which combines with... Figure 2 It can be seen that the protective layer is mainly composed of LiF and does not contain lithium-antimony alloy.

[0047] The lithium metal negative electrode sheets obtained above are assembled in the following order: positive electrode shell, lithium sheet, electrolyte, separator, electrolyte, lithium sheet, gasket, spring sheet, and negative electrode shell. Then they are pressed together to obtain a symmetrical battery.

[0048] Example 2

[0049] First, weigh 50 mg of AgSbF6 powder into a glass bottle, add 10 ml of acetonitrile solution, and seal the bottle with sealing film. Then, place the bottle on a magnetic stirrer and stir for 5 hours, maintaining the temperature at 30°C, to obtain a homogeneous mixture.

[0050] Next, the mixed solution obtained above is uniformly dropped onto the surface of a lithium metal sheet, controlling the mass ratio of AgSbF6 to lithium metal sheet to be 1:800. Then, it is placed on a heating table at 40°C for static drying to obtain a lithium metal anode sheet. The protective layer in this lithium metal anode sheet is composed of elemental Ag, elemental Sb, LiF, and a silver-antimony alloy.

[0051] The lithium metal negative electrode sheets obtained above are assembled in the following order: positive electrode shell, lithium sheet, electrolyte, separator, electrolyte, lithium sheet, gasket, spring sheet, and negative electrode shell. Then they are pressed together to obtain a symmetrical battery.

[0052] Example 3

[0053] First, weigh 20 mg of AgSbF6 powder into a glass bottle, add 10 ml of acetonitrile solution, and seal the bottle with sealing film. Then, place the bottle on a magnetic stirrer and stir for 5 hours, maintaining the temperature at 30°C, to obtain a homogeneous mixture.

[0054] Next, the mixed solution obtained above is uniformly dropped onto the surface of a lithium metal sheet, controlling the mass ratio of AgSbF6 to lithium metal sheet to be 1:2000. Then, it is placed on a heating table at 40°C for static drying to obtain a lithium metal anode sheet. The protective layer in this lithium metal anode sheet is composed of elemental Ag, elemental Sb, LiF, and a silver-antimony alloy.

[0055] The lithium metal negative electrode sheets obtained above are assembled in the following order: positive electrode shell, lithium sheet, electrolyte, separator, electrolyte, lithium sheet, gasket, spring sheet, and negative electrode shell. Then they are pressed together to obtain a symmetrical battery.

[0056] Example 4

[0057] First, weigh 10 mg of AgSbF6 powder into a glass bottle, add 10 ml of acetonitrile solution, and seal the bottle with sealing film. Then, place the bottle on a magnetic stirrer and stir for 5 hours, maintaining the temperature at 30°C, to obtain a homogeneous mixture.

[0058] Next, the mixed solution obtained above is uniformly dropped onto the surface of a lithium metal sheet, controlling the mass ratio of AgSbF6 to lithium metal sheet to be 1:4000. Then, it is placed on a heating table at 40°C for static drying to obtain a lithium metal anode sheet. The protective layer in this lithium metal anode sheet is composed of elemental Ag, elemental Sb, LiF, and a silver-antimony alloy.

[0059] The lithium metal negative electrode sheets obtained above are assembled in the following order: positive electrode shell, lithium sheet, electrolyte, separator, electrolyte, lithium sheet, gasket, spring sheet, and negative electrode shell. Then they are pressed together to obtain a symmetrical battery.

[0060] Example 5

[0061] First, weigh 50 mg of AgGeF6 powder into a glass bottle, add 10 ml of acetonitrile solution, and seal the bottle with sealing film. Then, place the bottle on a magnetic stirrer and stir for 5 hours, maintaining the temperature at 30°C, to obtain a homogeneous mixture.

[0062] Next, the mixed solution obtained above is uniformly dropped onto the surface of a lithium metal sheet, controlling the mass ratio of AgGeF6 to lithium metal sheet to be 1:800. Then, it is placed on a heating table at 40°C for static drying to obtain a lithium metal anode sheet. The protective layer in the lithium metal anode sheet is composed of elemental Ag, elemental Ge, LiF, and a silver-germanium alloy.

[0063] The lithium metal negative electrode sheets obtained above are assembled in the following order: positive electrode shell, lithium sheet, electrolyte, separator, electrolyte, lithium sheet, gasket, spring sheet, and negative electrode shell. Then they are pressed together to obtain a symmetrical battery.

[0064] Example 6

[0065] First, weigh 50 mg of AgSiF6 powder into a glass bottle, add 10 ml of acetonitrile solution, and seal the bottle with sealing film. Then, place the bottle on a magnetic stirrer and stir for 5 hours, maintaining the temperature at 30°C, to obtain a homogeneous mixture.

[0066] Next, the mixed solution obtained above is uniformly dropped onto the surface of a lithium metal sheet, controlling the mass ratio of AgSiF6 to lithium metal sheet to be 1:800. Then, it is placed on a heating table at 40°C for static drying to obtain a lithium metal anode sheet. The protective layer in the lithium metal anode sheet is composed of elemental Ag, elemental Si, LiF, and a silver-silicon alloy.

[0067] The lithium metal negative electrode sheets obtained above are assembled in the following order: positive electrode shell, lithium sheet, electrolyte, separator, electrolyte, lithium sheet, gasket, spring sheet, and negative electrode shell. Then they are pressed together to obtain a symmetrical battery.

[0068] Example 7

[0069] First, weigh 50 mg of AgAsF6 powder into a glass bottle, add 10 ml of acetonitrile solution, and seal the bottle with sealing film. Then, place the bottle on a magnetic stirrer and stir for 5 hours, maintaining the temperature at 30°C, to obtain a homogeneous mixture.

[0070] Next, the mixed solution obtained above is uniformly dropped onto the surface of a lithium metal sheet, controlling the mass ratio of AgAsF6 to lithium metal sheet to be 1:800. Then, it is placed on a heating table at 40°C for static drying to obtain a lithium metal anode sheet. The protective layer in this lithium metal anode sheet is composed of elemental Ag, elemental As, LiF, and a silver-arsenic alloy.

[0071] The lithium metal negative electrode sheets obtained above are assembled in the following order: positive electrode shell, lithium sheet, electrolyte, separator, electrolyte, lithium sheet, gasket, spring sheet, and negative electrode shell. Then they are pressed together to obtain a symmetrical battery.

[0072] Example 8

[0073] First, weigh 50 mg of AgAlF6 powder into a glass bottle, add 10 ml of acetonitrile solution, and seal the bottle with sealing film. Then, place the bottle on a magnetic stirrer and stir for 5 hours, maintaining the temperature at 30°C, to obtain a homogeneous mixture.

[0074] Next, the mixed solution obtained above is uniformly dropped onto the surface of a lithium metal sheet, controlling the mass ratio of AgAlF6 to lithium metal sheet to be 1:800. Then, it is placed on a heating table at 40°C for static drying to obtain a lithium metal anode sheet. The protective layer in this lithium metal anode sheet is composed of elemental Ag, elemental Al, LiF, and a silver-aluminum alloy.

[0075] The lithium metal negative electrode sheets obtained above are assembled in the following order: positive electrode shell, lithium sheet, electrolyte, separator, electrolyte, lithium sheet, gasket, spring sheet, and negative electrode shell. Then they are pressed together to obtain a symmetrical battery.

[0076] Comparative Example 1

[0077] First, weigh 50 mg of SbF3 powder into a glass bottle, add 10 ml of acetonitrile solution, and seal the bottle with sealing film. Then, place the bottle on a magnetic stirrer and stir for 5 hours, maintaining the temperature at 30°C, to obtain a homogeneous mixture.

[0078] Next, the mixed solution obtained above is uniformly dropped onto the surface of a lithium metal sheet, controlling the mass ratio of SbF3 to lithium metal sheet to be 1:800. Then, it is placed on a heating table at 40°C for static drying to obtain a lithium metal anode sheet. The protective layer in this lithium metal anode sheet is composed of a lithium-antimony alloy and LiF.

[0079] The lithium metal negative electrode sheets obtained above are assembled in the following order: positive electrode shell, lithium sheet, electrolyte, separator, electrolyte, lithium sheet, gasket, spring sheet, and negative electrode shell. Then they are pressed together to obtain a symmetrical battery.

[0080] Comparative Example 2

[0081] First, weigh 50 mg of LiSbF6 powder into a glass bottle, add 10 ml of acetonitrile solution, and seal the bottle with sealing film. Then, place the bottle on a magnetic stirrer and stir for 5 hours, maintaining the temperature at 30°C, to obtain a homogeneous mixed solution.

[0082] Next, the mixed solution obtained above is uniformly dropped onto the surface of a lithium metal sheet, controlling the mass ratio of LiSbF6 to lithium metal sheet to be 1:800. Then, it is placed on a heating table at 40°C for static drying to obtain a lithium metal anode sheet. The protective layer of this lithium metal anode sheet is composed of LiF and elemental Sb.

[0083] The lithium metal negative electrode sheets obtained above are assembled in the following order: positive electrode shell, lithium sheet, electrolyte, separator, electrolyte, lithium sheet, gasket, spring sheet, and negative electrode shell. Then they are pressed together to obtain a symmetrical battery.

[0084] Comparative Example 3

[0085] First, weigh 50 mg of AgSnF6 powder into a glass bottle, add 10 ml of acetonitrile solution, and seal the bottle with sealing film. Then, place the bottle on a magnetic stirrer and stir for 5 hours, maintaining the temperature at 30°C, to obtain a homogeneous mixture.

[0086] Next, the mixed solution obtained above is uniformly dropped onto the surface of a lithium metal sheet, controlling the mass ratio of AgSnF6 to lithium metal sheet to be 1:800. Then, it is placed on a heating table at 40°C for static drying to obtain a lithium metal anode sheet. The protective layer of the lithium metal anode sheet is composed of LiF, elemental Sn, and elemental Ag.

[0087] The lithium metal negative electrode sheets obtained above are assembled in the following order: positive electrode shell, lithium sheet, electrolyte, separator, electrolyte, lithium sheet, gasket, spring sheet, and negative electrode shell. Then they are pressed together to obtain a symmetrical battery.

[0088] Comparative Example 4

[0089] First, weigh 50 mg of AgSeF6 powder into a glass bottle, add 10 ml of acetonitrile solution, and seal the bottle with sealing film. Then, place the bottle on a magnetic stirrer and stir for 5 hours, maintaining the temperature at 30°C, to obtain a homogeneous mixture.

[0090] Next, the mixed solution obtained above is uniformly dropped onto the surface of a lithium metal sheet, controlling the mass ratio of AgSeF6 to lithium metal sheet to be 1:800. Then, it is placed on a heating table at 40°C for static drying to obtain a lithium metal anode sheet. The protective layer of the lithium metal anode sheet is composed of LiF, elemental Se, and elemental Ag.

[0091] The lithium metal negative electrode sheets obtained above are assembled in the following order: positive electrode shell, lithium sheet, electrolyte, separator, electrolyte, lithium sheet, gasket, spring sheet, and negative electrode shell. Then they are pressed together to obtain a symmetrical battery.

[0092] Comparative Example 5

[0093] First, weigh 50 mg of MgSiF6 powder into a glass bottle, add 10 ml of acetonitrile solution, and seal the bottle with sealing film. Then, place the bottle on a magnetic stirrer and stir for 5 hours, maintaining the temperature at 30°C, to obtain a homogeneous mixed solution.

[0094] Next, the mixed solution obtained above is uniformly dropped onto the surface of a lithium metal sheet, controlling the mass ratio of MgSiF6 to lithium metal sheet to be 1:800. Then, it is placed on a heating table at 40°C for static drying to obtain a lithium metal anode sheet. The protective layer of the lithium metal anode sheet is composed of LiF, elemental Si, and elemental Mg.

[0095] The lithium metal negative electrode sheets obtained above are assembled in the following order: positive electrode shell, lithium sheet, electrolyte, separator, electrolyte, lithium sheet, gasket, spring sheet, and negative electrode shell. Then they are pressed together to obtain a symmetrical battery.

[0096] The symmetrical cell obtained above was subjected to performance testing at 25℃ and 1 mA·cm. -2 The results were obtained under the specified conditions and are shown in Table 1.

[0097] Table 1

[0098]

[0099] As shown in Table 1, the lithium metal anode sheet obtained in the embodiments of the present invention has low polarization and good stability. When applied to secondary batteries, it can effectively improve the electrochemical performance and safety performance of secondary batteries.

[0100] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0101] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A method for preparing a lithium metal anode sheet, characterized in that, Includes the following steps: AgMF6 is mixed with an organic solvent to obtain a mixture, wherein M is selected from at least one of Ge, Si, Sb, As or Al; The mixture is formed on a lithium metal sheet and reacted to obtain a lithium metal anode sheet, wherein the lithium metal anode sheet includes a lithium metal sheet and a protective layer formed on the surface of the lithium metal sheet.

2. The method for preparing the lithium metal anode sheet according to claim 1, characterized in that, M is selected from Sb.

3. The method for preparing a lithium metal anode sheet according to claim 1, characterized in that, The concentration of AgMF6 in the mixture is 1 mg / ml to 10 mg / ml.

4. The method for preparing the lithium metal anode sheet according to claim 1, characterized in that, In the step of forming the mixture on a lithium metal sheet for reaction, the mass ratio of AgMF6 to the lithium metal sheet is 1:300-1:4000.

5. The method for preparing a lithium metal anode sheet according to claim 1, characterized in that, In the step of forming the mixture on a lithium metal sheet for reaction, the temperature is 40℃-80℃.

6. The method for preparing a lithium metal anode sheet according to any one of claims 1-5, characterized in that, The temperature during the step of mixing AgMF6 with the organic solvent is 25℃-40℃.

7. A lithium metal anode sheet obtained by the preparation method according to any one of claims 1-6.

8. A secondary battery, characterized in that, Including the lithium metal anode sheet as described in claim 7.

9. The secondary battery according to claim 8, characterized in that, The secondary battery is a lithium-ion battery.

10. An electrical device, characterized in that, The lithium-ion battery as described in claim 9 is used.

Images