A composite solid-state electrolyte material, a method for preparing the same, and use thereof in lithium-ion batteries

Abstract

The application discloses a kind of composite solid electrolyte material, its preparation method and in the purposes of lithium ion battery, the composite electrolyte material includes first layer, second layer and third layer sequentially stacked, the first layer is ceramic matrix layer, second layer and third layer constitute composite film layer, the second layer is the composite layer formed by electrolyte conductor wrapping Al2O3 Particle, the third layer is electrolyte conductor layer.The method includes:1) using electrolyte powder preparation ceramic matrix green body;2) preparation slurry containing Al2O3, by coating process, coating to the surface of ceramic green body, form Al2O3 Layer;3) preparation slurry containing lithium salt, by spraying process, form lithium salt layer on the surface of Al2O3 Layer;4) sintering, obtain composite solid electrolyte material.The ceramic base electrolyte prepared by the application can obtain higher interface ion conductance, good mechanical property and higher thermal stability.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of batteries, and relates to a composite solid-state electrolyte material, a preparation method thereof and application thereof in lithium ion batteries. BACKGROUND

[0002] Lithium ion batteries have been widely used in portable electronic products and electric vehicles due to their high working voltage, long cycle life, no memory effect, small self-discharge and environmental friendliness. At present, many countries including China have formulated a long-term strategic goal of further improving the energy density of power batteries to 300-400 watt-hours per kilogram.

[0003] The capacity of lithium metal is 3860mAh / g, which is about 10 times that of graphite, so lithium metal batteries with metal lithium as the negative electrode have become an inevitable choice. However, there are still no effective solutions to a series of technical problems of metal lithium negative electrode in liquid batteries, such as multiple interface side reactions between metal lithium and liquid electrolyte, uneven and unstable SEI film distribution leading to poor cycle life, and uneven deposition and dissolution of metal lithium leading to uneven lithium dendrites and holes, thereby causing battery safety problems.

[0004] For the above reasons, many researchers hope to solve the application problems of metal lithium negative electrode by using solid-state electrolyte. The main idea is to avoid the continuous side reactions in liquid electrolyte, and at the same time to use the mechanical and electrical properties of solid electrolyte to inhibit the formation of lithium dendrites.

[0005] The solid-state electrolyte NASICON structure phosphate has a composition of Li 1+x A x B 2-x (MO4)3, wherein x ranges from 0.05 to 0.7, A is one or more of Al, Ga, Sc, Y, Ca, Sr, Zn, Si, In, Lu, La, Fe, and Cr, B is Ti or Ge, and M is P or Si; the Perovskite structure titanate electrolyte has a composition of Li 3x M 1 / 3-2x La 2 / 3-x NO3, wherein x ranges from 0.01 to 0.16, M is one or more of Ca, Sr, Zn, Mg, Al, Sc, Y, In, and Cr, and N is one or two of Ti or Ge; Li 7+x Ge x P 3-x S 11 (LGPS), wherein x ranges from 0.05 to 2; has a wide electrochemical window, good thermal stability and excellent ionic conductivity.

[0006] However, this type of electrolyte also presents some problems when using lithium metal as the negative electrode. For example, Ti... 4+ Ge 4+ In actual working process, it is easily reduced to Ti. 3+ Ge 3+ This can damage the electrolyte crystal structure. Secondly, the oxidation process is also a process in which internal electrons pass through, causing a short circuit inside the electrolyte. Moreover, the battery will cause serious lithium dendrite problems during cycling. These factors limit the development of all-solid-state batteries.

[0007] Therefore, an effective method is needed to reduce the above-mentioned adverse effects and improve battery performance. Summary of the Invention

[0008] To address the aforementioned problems in the prior art, the present invention aims to provide a composite solid electrolyte material, its preparation method, and its application in lithium-ion batteries. In the composite solid electrolyte material of the present invention, a composite film layer with a specific structure is present on the surface of the ceramic substrate layer. Part of this composite film layer facilitates lithium-ion transport, while another part protects the ceramic-based electrolyte. Compared with existing ceramic-based solid electrolytes, the ceramic-based electrolyte prepared by the present invention achieves higher interfacial ionic conductivity. Simultaneously, the alumina protective layer enables the electrolyte to possess good mechanical properties and high thermal stability.

[0009] To achieve the above objectives, the present invention adopts the following technical solution:

[0010] In a first aspect, the present invention provides a composite solid electrolyte material (see schematic diagram of its structure). Figure 1 The composite electrolyte material comprises a first layer, a second layer, and a third layer stacked sequentially. The first layer is a ceramic matrix layer, the second and third layers constitute a composite film layer, the second layer is a composite layer formed by encapsulating Al2O3 particles with an electrolyte conductor, and the third layer is an electrolyte conductor layer.

[0011] The composite solid electrolyte material of this invention is an inorganic solid electrolyte material, which can achieve a lithium-ion conductivity in the range of 10 at room temperature. -5 ~10 -2 The composite inorganic solid electrolyte exhibits high stability against lithium metal and possesses excellent mechanical properties.

[0012] The following are preferred technical solutions of the present invention, but are not intended to limit the technical solutions provided by the present invention. The technical objectives and beneficial effects of the present invention can be better achieved and realized through the following preferred technical solutions.

[0013] Preferably, the composite film layer is formed by reacting Al2O3 particles with lithium salt, for example, under high-temperature sintering conditions.

[0014] Preferably, the thickness of the composite film layer is 0.1-50 μm, for example, 0.1 μm, 1 μm, 2 μm, 5 μm, 8 μm, 10 μm, 15 μm, 17.5 μm, 20 μm, 25 μm, 30 μm, 33 μm, 36 μm, 40 μm, 45 μm or 50 μm, etc. From the perspective of lithium ion kinetics, a composite layer that is too thick is not suitable for the passage of lithium ions, which can result in an increase in the transmission path of lithium ions and low ionic conductivity. Therefore, the above range is preferred, and further preferably 1-10 μm.

[0015] Preferably, the electrolyte conductor is LiAlO2.

[0016] Preferably, the ceramic matrix layer is a solid-state fast ionic ceramic matrix layer, and the chemical composition is a lithium ion conductor solid-state electrolyte, preferably including but not limited to: a NASICON-structured electrolyte and / or a perovskite-structured electrolyte.

[0017] Preferably, the chemical composition of the NASICON-structured electrolyte is Li 1+x A x B 2-x (MO4)3, wherein x ranges from 0.05 to 0.7, A includes any one or a combination of at least two of Al, Ga, Sc, Y, Ca, Sr, Zn, Si, In, Lu, La, Fe or Cr, B includes Ti and / or Ge, and M includes P and / or Si.

[0018] Preferably, the chemical composition of the perovskite-structured electrolyte is Li 3x M 1 / 3-2x La 2 / 3-x NO3, wherein x ranges from 0.01 to 0.17, M includes any one or a combination of at least two of Ca, Sr, Zn, Mg, Al, Sc, Y, In or Cr, and N includes any one or both of Ti or Ge.

[0019] The present application lists a small number of fast ionic conductors containing Ti and Ge with variable valence elements, but the patent is not limited to the protection of Ti and Ge elements. The protection of other ceramic matrices containing variable valence elements is also within the scope of protection of the present patent.

[0020] Preferably, the lithium ion conductor solid electrolyte D50 is 0.1-10 μm, such as 0.1 μm, 0.5 μm, 1 μm, 2 μm, 3 μm, 4 μm, 5 μm, 6 μm, 7 μm, 8 μm, 9 μm or 10 μm, etc. The D90 is 0.2 μm-20 μm, such as 0.2 μm, 0.5 μm, 1 μm, 2 μm, 4 μm, 5 μm, 6 μm, 7 μm, 8 μm, 9 μm, 10 μm, 12 μm, 14 μm, 15 μm, 18 μm or 20 μm, etc.

[0021] Preferably, the lithium ion conductor solid electrolyte is Li 1.3 Al 0.3 Ti 1.7 (PO4)3and Li 0.5 La 0.5 TiO3.

[0022] Preferably, the chemical composition of the Al2O3 particles includes any one or a combination of at least two of ɑ-Al2O3, β-Al2O3 or γ-Al2O3. Of the three different crystal forms of Al2O3, ɑ-Al2O3 is preferred because the solid phase reaction between Al2O3 and lithium carbonate is an interface diffusion process. During the diffusion process, lithium carbonate and other lithium salts unidirectionally diffuse into aluminum oxide to form LiAlO2, or lithium ions and aluminum ions diffuse through the oxygen ion lattice gap to form fast ion conductors. Therefore, the use of ɑ-Al2O3 can more easily obtain relatively pure ɑ-LiAlO2 fast ion conductors, and such electrolytes have high ionic conductivity.

[0023] Preferably, the particle size D50 of the Al2O3 particles is 1-50 μm, such as 1 μm, 3 μm, 4 μm, 5 μm, 6 μm, 8 μm, 10 μm, 11 μm, 12 μm, 14 μm, 18 μm, 22 μm, 25 μm, 30 μm, 35 μm, 38 μm, 40 μm, 45 μm or 50 μm, etc.

[0024] Preferably, the Al2O3 particles are ɑ-Al2O3 with a D50 of 1-2 μm.

[0025] In a second aspect, the present application provides a method for preparing the composite solid electrolyte material according to the first aspect, characterized in that the method comprises the following steps:

[0026] (1) using electrolyte powder to prepare a ceramic matrix green body by a molding process;

[0027] (2) preparing a slurry containing Al2O3, and coating the slurry onto the surface of the ceramic green body of step (1) by a coating process to form an Al2O3 layer;

[0028] (3) preparing a slurry containing lithium salt, and forming a lithium salt layer on the surface of the Al2O3 layer by a spraying process;

[0029] (4) sintering to obtain the composite solid electrolyte material.

[0030] The method of the present application combines a coating process and a spraying process to sequentially form an Al2O3 layer and a lithium salt layer on the surface of the ceramic substrate green body, and through a sintering process, the surface of the Al2O3 particles in the Al2O3 layer reacts with the lithium salt to form an electrolyte conductor composite film layer. The ceramic substrate layer is the first layer, and the composite film layer includes a second layer and a third layer. The second layer is in contact with the ceramic substrate layer, specifically Al2O3 particles and electrolyte conductors wrapping the Al2O3 particles. The third layer is actually integrated with the second layer and is located on the surface of the second layer, specifically an electrolyte conductor. In the composite solid electrolyte material prepared by the method, the surface of the ceramic substrate layer has a composite film layer with a specific structure. Part of the composite film layer plays a role in transporting lithium ions, and the other part plays a protective role for the ceramic electrolyte. Therefore, it has higher interface ion conductivity, excellent mechanical properties and higher thermal stability.

[0031] In the method of the present application, the Al2O3 layer must be formed on the surface of the ceramic green body in step (2) by a coating process, and then the lithium salt layer is formed on the surface of the Al2O3 layer in step (3) by a spraying process.

[0032] If the spraying process is used in step (2), the density of the Al2O3 layer formed by spraying will be low, and the second layer (specifically Al2O3 particles and electrolyte conductors wrapping the Al2O3 particles) in the product cannot play an effective protective role.

[0033] If the coating process is used in step (3), the aluminum oxide layer in the lower layer will be easily damaged during the coating process. If the spraying process is used, the operation process will be very simple, and a relatively ideal effect can be achieved.

[0034] As a preferred technical solution of the method of the present application, the forming process in step (1) includes any one of cold isostatic pressing, tape casting or calendering, and the cold isostatic pressing is preferred.

[0035] Preferably, the cold isostatic pressing is used in step (1) to prepare the ceramic substrate green body, and the pressure of the tabletting is controlled to be 50-150 MPa, such as 50 MPa, 60 MPa, 75 MPa, 85 MPa, 100 MPa, 110 MPa, 120 MPa, 130 MPa, 140 MPa or 150 MPa, etc.

[0036] Preferably, the electrolyte powder in step (1) has a D50 of 0.1-10 μm, such as 0.1 μm, 0.5 μm, 1 μm, 2 μm, 4 μm, 5 μm, 6 μm, 7 μm, 8 μm, 9 μm or 10 μm, etc. The D90 is 0.2 μm-20 μm, such as 0.2 μm, 0.5 μm, 1 μm, 2 μm, 4 μm, 5 μm, 6 μm, 7 μm, 8 μm, 9 μm, 10 μm, 12 μm, 14 μm, 15 μm, 18 μm or 20 μm, etc.

[0037] Preferably, the ceramic matrix green body in step (1) is prepared by cold isostatic pressing, and the diameter of the prepared ceramic matrix green body is preferably 2-15 mm, such as 2 mm, 5 mm, 8 mm, 10 mm, 12 mm or 15 mm, etc. The thickness is preferably 1-5 mm, such as 1 mm, 2 mm, 3 mm, 3.5 mm, 4 mm or 5 mm, etc.

[0038] Preferably, the ceramic matrix green body in step (1) is a solid fast ionic ceramic matrix green body.

[0039] As a preferred technical solution of the method of the present application, the Al2O3 in step (2) comprises any one or at least two combinations of ɑ-Al2O3, β-Al2O3 or γ-Al2O3, preferably ɑ-Al2O3.

[0040] Preferably, the particle size D50 of the Al2O3 in step (2) is 1-50 μm, such as 1 μm, 5 μm, 10 μm, 13 μm, 16 μm, 20 μm, 25 μm, 30 μm, 35 μm, 40 μm, 45 μm or 50 μm, etc., preferably 1-2 μm.

[0041] Preferably, the Al2O3 in step (2) is ɑ-Al2O3 with a particle size D50 of 2-10 μm. The surface of small-particle-size alumina has a relatively high interfacial energy, which is conducive to the formation of small-particle-size LiAlO2. The use of ɑ-Al2O3 can more easily obtain relatively pure ɑ-LiAlO2 fast ionic conductor, and the ionic conductivity of such electrolyte is relatively high.

[0042] Preferably, the particle size of the Al2O3 in step (2) is smaller than the particle size of the electrolyte powder, preferably slightly smaller than the particle size of the electrolyte powder. In this way, the alumina powder is coated on the tablet pressed from the electrolyte powder, and a part of the alumina is distributed between the particles of the pressed tablet. After the later spraying of lithium salt and sintering, the LiAlO2 electrolyte formed can be more closely integrated with the matrix to form a dense layer.

[0043] Preferably, the solvent used for the preparation of the slurry in step (2) comprises any one or at least two combinations of deionized water, methanol, ethanol, isopropanol, acetone, butanone or trichloroethylene, preferably deionized water.

[0044] Preferably, the thickness of the Al2O3 layer prepared by the coating of step (2) is 1-8 μm, such as 1 μm, 2 μm, 3 μm, 4 μm, 5 μm, 6.5 μm, or 7.5 μm, and the like, further preferably 1-5 μm.

[0045] Preferably, the dispersant comprises any one or a combination of at least two of polyethylene glycol, polymethacrylic acid, polyacrylic acid, acrylic acid-acrylic ester copolymer, or polyvinylpyrrolidone.

[0046] The present application can form a single layer or a relatively thin layer of Al2O3 in the coating process by using Al2O3 of a suitable size, a solvent, and a dispersant, so as to provide a reaction platform for the subsequent sprayed lithium salt, and generate a composite layer of thin layers of Al2O3 and LiAlO2.

[0047] Preferably, the content of the dispersant is 0.5-10 wt.%, such as 0.5 wt.%, 1 wt.%, 2 wt.%, 2.5 wt.%, 3 wt.%, 3.5 wt.%, 4 wt.%, 4.5 wt.%, 5 wt.%, 5.5 wt.%, 6 wt.%, 6.5 wt.%, 7 wt.%, 7.5 wt.%, 8 wt.%, 8.5 wt.%, 9 wt.%, 9.5 wt.%, 10 wt.%, and the like, preferably 2-6 wt.%, based on the total mass of the slurry of step (2).

[0048] Preferably, the solid content of the slurry of step (2) is 5-30%, such as 5%, 10%, 12%, 15%, 18%, 20%, 25%, 26%, 28%, or 30%, and the like, preferably 10-15%.

[0049] The step (2) of the present application coats the slurry containing Al2O3 to the surface of the ceramic body of step (1) by coating process to form the Al2O3 layer, and the surface of Al2O3 particles in the Al2O3 layer reacts with lithium salt to form the electrolyte conductor composite film layer in the subsequent sintering step. Part of the composite film layer plays a role in transmitting lithium ions, and the other part plays a role in protecting the ceramic-based electrolyte. The solid content of the slurry of step (2) needs to be controlled within a suitable range. If the solid content is less than 10%, the slurry is too dilute, resulting in that after sintering reaction, the Al2O3 particles in the second layer formed cannot effectively improve the mechanical properties, so that the Al2O3 layer cannot play an effective protection role. If the solid content is greater than 30%, the slurry is too thick, resulting in that the Al2O3 layer formed by coating is too thick, and only the Al2O3 particles on the surface layer which contacts with lithium salt react with lithium salt to form the electrolyte conductor layer after sintering, and the Al2O3 particles which do not contact do not react, which is equivalent to an extra Al2O3 layer between the first layer and the second layer, which is not conductive, and the lithium ion transmission conductivity between the first layer and the second layer is reduced.

[0050] The present application does not limit the specific operation of preparing the slurry containing Al2O3 in step (2). For example, Al2O3 and dispersant can be added to the solvent in a certain proportion to prepare the uniformly dispersed Al2O3 slurry. The dispersant can also be dispersed in the solvent first, and then Al2O3 is added to prepare the uniformly dispersed Al2O3 slurry.

[0051] As a preferred technical solution of the method of the present application, the lithium salt of step (3) includes any one or a combination of at least two of lithium carbonate, lithium nitrate, lithium oxalate, lithium acetate or lithium citrate. The lithium salt can react with Al2O3 to form an electrolyte conductor layer under high temperature (such as 600-900°C), and preferably a lithium salt which can react with Al2O3 to form an inorganic fast ion conductor, such as LiAlO2.

[0052] Preferably, the solvent used in the preparation of the slurry of step (3) includes any one or a combination of at least two of deionized water, methanol, ethanol, isopropyl alcohol or butanone, and preferably acetone.

[0053] Preferably, the dispersant is also included in the preparation of the slurry of step (3), and the dispersant includes any one or a combination of at least two of polyethylene glycol, polymethylacrylic acid, polyacrylic acid, acrylic acid-acrylic ester copolymer or polyvinylpyrrolidone.

[0054] Preferably, the content of the dispersant is 0.5-8 wt.%, such as 0, 0.2 wt.%, 0.5 wt.%, 1 wt.%, 1.5 wt.%, 2.5 wt.%, 3 wt.%, 4 wt.%, 5 wt.%, 5.5 wt.%, 6 wt.%, 7 wt.%, or 8 wt.% and the like, preferably 3-5 wt.% based on the total mass of the slurry in step (3).

[0055] Preferably, the solid content of the slurry in step (3) is 0.1-50%, such as 0.1%, 0.5%, 1%, 3%, 5%, 8%, 12%, 16%, 20%, 25%, 30%, 35%, 40%, 45%, or 50% and the like, preferably 5-13%.

[0056] Since the lithium salt layer is formed on the surface of the Al2O3 layer in step (3) by the spraying process, and the surface of the Al2O3 particles in the Al2O3 layer reacts with the lithium salt to form the electrolyte conductor composite film layer through the subsequent sintering step, part of the composite film layer plays a role in the transmission of lithium ions, and the other part plays a protective role for the ceramic-based electrolyte, so the solid content of the slurry in step (3) should be controlled within a suitable range. If the solid content is less than 0.1%, the slurry is too dilute, which will result in insufficient amount of reactant lithium salt to react with Al2O3 to form the electrolyte conductor layer to play the role of effective transmission of lithium ions; if the solid content is greater than 50%, the slurry is too thick, and part of the lithium salt does not participate in the reaction and remains on the surface of the sample, such as Li2CO3 and LiOH and the like impurities, which will form an impurity layer, the impurity layer has a low conductivity of lithium ions in the solid state, which will greatly reduce the conductivity of lithium ions, so the formation of the impurity layer should be avoided.

[0057] The present application does not limit the specific operation of preparing the slurry containing lithium salt in step (3), for example, the lithium salt and the dispersant can be added to the solvent in a certain proportion to prepare a uniformly dispersed lithium salt slurry.

[0058] The specific operation of the spraying process in step (3) of the present application can be, for example, using a spray gun to uniformly spray the prepared slurry containing lithium salt onto the surface of the Al2O3 layer to form a lithium salt layer.

[0059] Preferably, the thickness of the lithium salt layer in step (3) is 1-3 μm, such as 1 μm, 1.2 μm, 1.5 μm, 1.7 μm, 2 μm, 2.2 μm, 2.5 μm, or 3 μm and the like, preferably 1-2 μm.

[0060] As a preferred technical solution of the method of the present application, the device used for sintering in step (4) includes any one or a combination of at least two of a muffle furnace, a tube furnace, a box furnace or a rotary furnace, but is not limited to the above-mentioned sintering furnaces, and other commonly used sintering furnaces in the art that can achieve the same effect can also be used in the present application.

[0061] In the present application, the sintering temperature needs to be controlled within a suitable range, on the one hand to ensure that the lithium salt reacts with Al2O3 to generate an electrolyte conductor, and on the other hand to avoid excessive temperature leading to decomposition of the ceramic matrix layer and generating impurities such as AlPO4, and excessive temperature leading to destruction of the crystal structure of the ceramic matrix layer, which is not conducive to the conduction of lithium ions.

[0062] In order to better achieve the effect of generating an electrolyte conductor by the above-mentioned reaction and avoiding the generation of impurities, the sintering temperature in step (4) is preferably 600-900℃, such as 600℃, 650℃, 700℃, 750℃, 800℃, 850℃ or 900℃, etc.

[0063] Preferably, the sintering time in step (4) is 3-12h, such as 3h, 5h, 6h, 8h, 10h, 11h or 12h, etc.

[0064] Preferably, the heating rate for heating to the sintering temperature is 1-10℃ / min, such as 1℃ / min, 1.5℃ / min, 2℃ / min, 3℃ / min, 4℃ / min, 5℃ / min, 8℃ / min or 10℃ / min, etc.

[0065] Preferably, the sintering atmosphere in step (4) is any one or a combination of at least two of air, oxygen, nitrogen, helium or neon.

[0066] Preferably, the method further comprises a drying step after step (3) and before step (4).

[0067] As a further preferred technical solution of the method of the present application, the method comprises the following steps:

[0068] (1) preparing a PVA aqueous solution, adding electrolyte powder, grinding, and using cold isostatic pressing to press the ground electrolyte powder into a ceramic matrix green body under a pressure of 50-150MPa;

[0069] (2) preparing an aqueous solution using polyacrylic acid as a dispersant, taking D50 1-2μm α-Al2O3 in the above-mentioned aqueous solution, preparing a slurry with a solid content of 10-30%, using ammonia water to adjust the pH value of the solution to 8-9, and using a coating method to coat the prepared slurry on the surface of the ceramic green body prepared in step (1);

[0070] (3) using lithium salt, dispersant and acetone to prepare slurry with solid content of 5-13%, wherein the dispersant is polyacrylic acid, and the content of the dispersant accounts for 1wt.% of the slurry, and the prepared slurry is sprayed onto the α-Al2O3 coating layer prepared in step (2) by using a spray gun to form a lithium salt layer on the surface of α-Al2O3;

[0071] (4) drying the composite electrolyte prepared in step (3), and then sintering at 600-900℃ for 3-12h to form a composite layer of α-Al2O3 and LiAlO2 on the surface of the ceramic electrolyte, thereby obtaining the composite solid-state electrolyte material.

[0072] In the preferred technical solution, the use of PVA aqueous solution in step (1) is mainly to increase the binding effect of electrolyte powder in the granulation process, so that microspheres are more easily formed between the particles, and the green body is more dense and less likely to be brittle.

[0073] In a third aspect, the application provides a lithium ion battery comprising the composite solid-state electrolyte material of the first aspect.

[0074] Preferably, the lithium ion battery is a lithium ion all-solid-state battery.

[0075] Preferably, the lithium ion battery uses metallic lithium as the negative electrode.

[0076] Compared with the prior art, the application has the following beneficial effects:

[0077] (1) In the composite solid-state electrolyte material of the application, the surface of the ceramic matrix layer has a composite film layer with a specific structure, part of the composite film layer plays a transmission role for lithium ions, and the other part plays a protective role for the ceramic base electrolyte. Compared with the existing ceramic base solid-state electrolyte, the ceramic base electrolyte prepared by the application can obtain higher interface ion conductivity, and the aluminum oxide protective layer can make the electrolyte have good mechanical properties and high thermal stability.

[0078] The composite solid-state electrolyte of the application can obtain a lithium ion conductivity range of 10 -5 S / cm-10 - 2 S / cm at room temperature, and the composite solid-state electrolyte can have high stability to metallic lithium and excellent mechanical properties.

[0079] (2) The method of the application combines coating and spraying methods, and through subsequent sintering process, a composite solid-state electrolyte (which is a composite inorganic ceramic electrolyte film) with excellent performance is prepared, and the process of the application is simple and can be applied to industrial production. BRIEF DESCRIPTION OF DRAWINGS

[0080] Figure 1 is a structural schematic diagram of the composite solid electrolyte material of the present application. DETAILED DESCRIPTION

[0081] The technical solutions of the present application will be further described below in combination with the drawings and through specific embodiments.

[0082] The composite solid electrolyte of the present application will be further described below in combination with examples of the present application, and it should be understood by those skilled in the art that the examples are only used to help understand the present application and should not be regarded as specific limitations on the present application.

[0083] Example 1

[0084] The present embodiment provides a composite solid electrolyte material, which comprises a ceramic matrix layer and a composite film layer formed on the surface thereof, the ceramic matrix layer is Li 1.3 Al 0.3 Ti 1.7 (PO4)3.

[0085] The preparation method of the composite solid electrolyte material is as follows:

[0086] (1) A 5wt.% PVA aqueous solution is prepared, a certain amount of electrolyte powder with D50 of 0.5 μm and D90 of 1 μm is added into a mortar at a mass ratio of electrolyte ceramic powder to PVA solution of 95:5, uniformly ground for 30 min, and the ground electrolyte powder is pressed into a ceramic electrolyte green body under a pressure of 130 MPa;

[0087] (2) A 5wt.% aqueous solution is prepared with polyacrylic acid as a dispersant. A D50 of 2 μm α-Al2O3 is taken in the dispersant to prepare a slurry with a solid content of 10%, and after adjusting the pH value of the solution to 9 with ammonia water, ultrasonic is used for 1 h.

[0088] The prepared slurry is used to prepare an Al2O3 film on the surface of the ceramic green body prepared in step (1) by coating method. The specific method is as follows: the prepared electrolyte sheet is placed on a coating plate with a concave hole, the radius of the concave hole is equal to the radius of the electrolyte ceramic sheet. Then the slurry is poured on the coating plate, and the coating rod is pulled uniformly at a speed of 15 mm / min to prepare an Al2O3 film on the surface of the electrolyte sheet, and the thickness of the prepared film is 3 μm;

[0089] (3) A slurry with a solid content of 5% is prepared with lithium nitrate as lithium salt, polyacrylic acid as dispersant and acetone as solvent, and the content of the dispersant is 1wt.%.

[0090] The prepared slurry is sprayed onto the α-Al2O3 coating layer prepared in the previous step using a spray gun to form a lithium nitrate layer on the surface of the α-Al2O3. The specific method is as follows: the air pressure is 1 MPa, the gun mouth is perpendicular to the ceramic sheet, the distance between the gun mouth and the electrolyte sheet is 10 cm, the gun nozzle diameter is 0.5 mm, and the lithium salt layer on the surface of the ceramic sheet is prepared.

[0091] (4) The composite electrolyte prepared in the previous step is placed in a drying box at 100°C and dried for 12 hours. The dried sample is taken out and sintered in a muffle furnace at 650°C for 12 hours to form a composite layer of α-Al2O3 and LiAlO2 on the surface of the ceramic electrolyte, thereby preparing an inorganic composite electrolyte.

[0092] Example 2

[0093] This embodiment provides a composite solid-state electrolyte material, which includes a ceramic substrate layer and a composite film layer formed on the surface thereof, the ceramic substrate layer is Li 0.5 La 0.5 TiO3.

[0094] The preparation method of the composite solid-state electrolyte material is as follows:

[0095] (1) A 5wt.% PVA aqueous solution is prepared, a certain amount of electrolyte powder with D50 of 1 μm and D90 of 2 μm is added to a mortar in a ratio of 95:5 of electrolyte ceramic powder to PVA solution, and uniformly ground for 30 minutes. The ground electrolyte powder is pressed into a ceramic electrolyte green body under a pressure of 130 MPa.

[0096] (2) A 5wt.% aqueous solution of polyacrylic acid is prepared as a dispersant. A D50 of 3 μm α-Al2O3 is prepared into a slurry with a solid content of 10% in the dispersant, and the pH value of the solution is adjusted to 9 using ammonia water and then ultrasonic for 1 hour.

[0097] The prepared slurry is used to prepare an Al2O3 film on the surface of the ceramic green body prepared in step (1) using a coating method. The specific method is as follows: the prepared electrolyte sheet is placed on a coating plate with a concave hole, the radius of the concave hole is equal to the radius of the electrolyte ceramic sheet. Then the slurry is poured on the coating plate, and the coating rod is pulled uniformly at a speed of 30 mm / min to prepare an Al2O3 film on the surface of the electrolyte sheet, and the thickness of the prepared film is 4 μm.

[0098] (3) Lithium nitrate is used as lithium salt, polyacrylic acid is used as dispersant, and acetone is used as solvent to prepare a slurry with a solid content of 5%, and the content of the dispersant is 1wt.%.

[0099] The prepared slurry is sprayed onto the α-Al2O3 coating layer prepared in the previous step using a spray gun to form a lithium nitrate layer on the surface of the α-Al2O3. The specific method is as follows: the air pressure is 1 MPa, the gun mouth is perpendicular to the ceramic sheet, the gun mouth is 10 cm away from the electrolyte sheet, the spray gun nozzle diameter is 0.5 mm, and the lithium salt layer is prepared on the surface of the ceramic sheet.

[0100] (4) The composite electrolyte prepared in the previous step is placed in a drying box at 100°C and dried for 12 hours. The dried sample is taken out and sintered in a muffle furnace at 680°C for 12 hours to form a composite layer of α-Al2O3 and LiAlO2 on the surface of the ceramic electrolyte, thereby preparing an inorganic composite electrolyte.

[0101] Example 3

[0102] The present embodiment provides a composite solid-state electrolyte material, which includes a ceramic substrate layer and a composite film layer formed on the surface thereof, the ceramic substrate layer is Li 1.3 Al 0.3 Ti 1.7 (PO4)3.

[0103] The preparation method of the composite solid-state electrolyte material is as follows:

[0104] (1) A 5wt.% PVA aqueous solution is prepared, a certain amount of electrolyte powder with D50 of 0.5 μm and D90 of 1.5 μm is added to a mortar in a ratio of electrolyte ceramic powder to PVA solution of 95:5, and uniformly ground for 30 minutes. The ground electrolyte powder is pressed into a ceramic electrolyte green body under a pressure of 130 MPa;

[0105] (2) A 5wt.% aqueous solution of polymethyl methacrylate is prepared as a dispersant. A D50 of 2 μm α-Al2O3 is prepared in the dispersant to prepare a slurry with a solid content of 10%, and the pH value of the solution is adjusted to 9 using ammonia water and then ultrasonic for 1 hour.

[0106] The prepared slurry is used to prepare an Al2O3 film on the surface of the ceramic green body prepared in step (1) using a coating method. The specific method is as follows: the prepared electrolyte sheet is placed on a coating plate with a concave hole, the radius of the concave hole is equal to the radius of the electrolyte ceramic sheet. Then the slurry is poured on the coating plate, and the coating rod is pulled uniformly at a speed of 50 mm / min to prepare an Al2O3 film on the surface of the electrolyte sheet, and the thickness of the prepared film is 5 μm;

[0107] (3) Lithium carbonate is used as lithium salt, polyacrylic acid is used as dispersant, and ethanol is used as solvent to prepare a slurry with a solid content of 5%, and the content of the dispersant is 3wt.%.

[0108] The prepared slurry is sprayed onto the α-Al2O3 coating layer prepared in the previous step using a spray gun to form a lithium carbonate layer on the surface of the α-Al2O3. The specific method is as follows: the air pressure is 1 MPa, the gun mouth is perpendicular to the ceramic sheet, the distance between the gun mouth and the electrolyte sheet is 15 cm, the nozzle diameter of the spray gun is 0.5 mm, and the lithium salt layer is prepared on the surface of the ceramic sheet.

[0109] (4) The composite electrolyte prepared in the previous step is placed in a drying box at 100°C and dried for 12 hours. The dried sample is taken out and sintered in a muffle furnace at 750°C for 12 hours to form a composite layer of α-Al2O3 and LiAlO2 on the surface of the ceramic electrolyte, thereby preparing an inorganic composite electrolyte.

[0110] Example 4

[0111] The present embodiment provides a composite solid-state electrolyte material, which includes a ceramic substrate layer and a composite film layer formed on the surface thereof, the ceramic substrate layer is Li 1.3 Al 0.3 Ti 1.7 (PO4)3.

[0112] The preparation method of the composite solid-state electrolyte material is as follows:

[0113] (1) A 5wt.% PVA aqueous solution is prepared, a certain amount of electrolyte powder with a D50 of 0.5μm and a D90 of 2μm is added to a mortar in a ratio of 95:5 of electrolyte ceramic powder to PVA solution, and uniformly ground for 30 minutes. The ground electrolyte powder is pressed into a ceramic electrolyte green body under a pressure of 100 MPa;

[0114] (2) A 3wt.% aqueous solution of polymethyl methacrylate is prepared as a dispersant. A D50 of 3μm of α-Al2O3 is prepared in the dispersant to prepare a slurry with a solid content of 15%, and the pH value of the solution is adjusted to 9 using ammonia water and then ultrasonic for 1.5h.

[0115] The prepared slurry is used to prepare an Al2O3 film on the surface of the ceramic green body prepared in step (1) using a coating method. The specific method is as follows: the prepared electrolyte sheet is placed on a coating plate with a concave hole, the radius of the concave hole is equal to the radius of the electrolyte ceramic sheet. Then the slurry is poured on the coating plate, and the coating rod is pulled uniformly at a speed of 40mm / min to prepare an Al2O3 film on the surface of the electrolyte sheet, and the thickness of the prepared film is 6μm;

[0116] (3) Lithium carbonate is used as lithium salt, polyacrylic acid is used as dispersant, and ethanol is used as solvent to prepare a slurry with a solid content of 5%, and the content of the dispersant is 3wt.%.

[0117] The prepared slurry is sprayed onto the α-Al2O3 coating layer prepared in the previous step using a spray gun to form a lithium carbonate layer on the surface of the α-Al2O3. The specific method is as follows: the air pressure is 1 MPa, the spray gun nozzle is perpendicular to the ceramic sheet, the distance between the spray gun nozzle and the electrolyte sheet is 15 cm, the spray gun nozzle diameter is 0.5 mm, and the lithium salt layer is prepared on the surface of the ceramic sheet.

[0118] (4) The composite electrolyte prepared in the previous step is placed in a drying box at 100°C and dried for 12 hours. The dried sample is taken out and sintered in a muffle furnace at 750°C for 12 hours to form a composite layer of α-Al2O3 and LiAlO2 on the surface of the ceramic electrolyte, thereby preparing an inorganic composite electrolyte.

[0119] Example 5

[0120] Except that steps (2) and (3) do not add a dispersant, the other preparation methods and conditions are the same as in Example 1.

[0121] Example 6

[0122] Except that the solid content in step (2) is adjusted from 10% to 30%, the other methods and conditions are the same as in Example 2.

[0123] Example 7

[0124] Except that the solid content in step (3) is adjusted from 5% to 20%, the other methods and conditions are the same as in Example 1.

[0125] Comparative Example 1

[0126] This example provides a solid-state electrolyte, the ceramic matrix layer of which is Li 1.3 Al 0.3 Ti 1.7 (PO4)3.

[0127] The preparation method of the solid-state electrolyte is as follows:

[0128] (1) A 5wt.% PVA aqueous solution is prepared, a certain amount of electrolyte powder with a particle size D50 of 0.5 μm is taken, and the electrolyte ceramic powder and the PVA solution are added to the mortar in a mass ratio of 95:5, and uniformly ground for 30 min. The ground electrolyte powder is pressed into a ceramic electrolyte green body under a pressure of 130 MPa;

[0129] (2) The dried sample is taken out and sintered in a muffle furnace at 650°C for 12 hours to prepare a solid-state electrolyte.

[0130] Comparative Example 2

[0131] This example provides a solid-state electrolyte, the ceramic matrix layer of which is Li 0.5La 0.5 TiO3.

[0132] Preparation of ceramic electrolyte:

[0133] The preparation method of the solid-state electrolyte is as follows:

[0134] (1) A 5wt.% PVA aqueous solution is prepared, a certain amount of 1 μm electrolyte powder is taken, and the electrolyte ceramic powder and the PVA solution are added to a mortar in a mass ratio of 90:10, and uniformly ground for 30 min. The ground electrolyte powder is pressed into a ceramic electrolyte green body under a pressure of 100 MPa;

[0135] (2) The above dried sample is taken out and sintered at 850°C for 10 h in a muffle furnace, thereby preparing a solid-state electrolyte.

[0136] Comparative Example 3

[0137] Except that the sintering temperature of step (3) is adjusted to 1200°C, the other methods and conditions are the same as in Example 1.

[0138] The solid-state electrolyte materials prepared in Examples 1-7 and Comparative Examples 1-3 are tested for room temperature (25°C) ionic conductivity, mechanical strength, and composite film thickness. The testing methods are as follows:

[0139] Ionic conductivity: The ionic conductivity is tested using electrochemical impedance spectroscopy under the test condition of room temperature (25°C).

[0140] Mechanical strength: The sintered ceramic electrolyte sheet is tested for mechanical strength using an XLS205 strength tester, and the mechanical strength is characterized by the formula F=P / V, where F is the mechanical strength of the electrolyte sheet, P is the maximum breaking load, and V is the volume of the electrolyte sheet.

[0141] Composite film thickness: Scanning electron microscopy is used for measurement.

[0142] The test results are shown in Table 1.

[0143] Table 1 Data of Examples and Comparative Examples

[0144]

[0145] From the above data analysis, it can be seen that:

[0146] The thicker the thickness of the composite film, the less conducive to the improvement of lithium ion conductivity. Moreover, the increase of the solid content of aluminum oxide in the composite film increases the thickness of the aluminum oxide film, improves the material's breaking resistance, and is not conducive to the transmission of lithium ions.

[0147] Secondly, the thickness of the film obtained by sintering the samples at different temperatures is different, which shows that the aluminum oxide layer and the lithium salt layer participate in the reaction during the sintering process, and the non-basic electrolyte layer (LiAlO2) is generated.

[0148] Comparative analysis of the examples and the comparative examples, the electrolyte with the composite film layer not only improves the ionic conductivity, but also improves the mechanical properties of the material, so as to resist the penetration of lithium dendrite and obtain higher mechanical properties.

[0149] The above describes the main steps and main parameters of the present application, but the present application is not limited to the above steps and the materials used, the core of the patent protection is to prepare a composite solid electrolyte material by combining coating and spraying, and any improvement and reprocessing method in the above steps is also within the protection scope of the patent.

[0150] The applicant declares that the present application is illustrated by the above examples, but the present application is not limited to the above detailed method, that is, it does not mean that the present application must rely on the above detailed method to be implemented. It should be understood by those skilled in the art that any improvement of the present application, equivalent replacement of each raw material of the product of the present application, addition of auxiliary ingredients, selection of specific methods, etc. are all within the protection scope and disclosure scope of the present application.

Claims

1. A composite solid-state electrolyte material, characterized by, The composite electrolyte material comprises a first layer, a second layer and a third layer stacked in sequence, the first layer is a ceramic matrix layer, the second layer and the third layer form a composite membrane layer, the second layer is a composite layer formed by electrolyte conductor wrapping Al2O3 particles, the third layer is an electrolyte conductor layer, and the electrolyte conductor is LiAlO2. The ceramic matrix layer is a solid-state fast ionic ceramic matrix layer, and the chemical composition is a lithium ion conductor solid-state electrolyte.

2. The composite solid-state electrolyte material of claim 1, wherein, The composite membrane layer is formed by the reaction of Al2O3 particles and lithium salt.

3. The composite solid-state electrolyte material of claim 1, wherein, The thickness of the composite membrane layer is 0.1-50 μm.

4. The composite solid-state electrolyte material of claim 3, wherein, The thickness of the composite membrane layer is 1-10 μm.

5. The composite solid-state electrolyte material of claim 1, wherein, The lithium ion conductor solid-state electrolyte comprises an electrolyte with a NASICON structure and / or an electrolyte with a perovskite structure.

6. The composite solid-state electrolyte material of claim 5, wherein, The chemical composition of the electrolyte of the NASICON structure is Li 1+x A x B 2-x (M04)3, wherein x ranges from 0.05 to 0.7, A comprises any one or a combination of at least two of Al, Ga, Sc, Y, Ca, Sr, Zn, Si, In, Lu, La, Fe or Cr, B comprises Ti and / or Ge, and M comprises P and / or Si.

7. The composite solid-state electrolyte material of claim 5, wherein, The chemical composition of the perovskite structure electrolyte is Li 3x M 1 / 3-2x La 2 / 3-x NO3, wherein x ranges from 0.01 to 0.17, M includes any one or a combination of at least two of Ca, Sr, Zn, Mg, Al, Sc, Y, In or Cr, and N includes any one or both of Ti or Ge.

8. The composite solid-state electrolyte material of claim 1, wherein, The D50 of the lithium ion conductor solid-state electrolyte is 0.1-10 μm, and the D90 is 0.2 μm-20 μm.

9. The composite solid-state electrolyte material of claim 8, wherein, The lithium ion conductor solid electrolyte is Li 1.3 Al 0.3 Ti 1.7 (PO4)3and Li 0.5 La 0.5 TiO3.

10. The composite solid-state electrolyte material of claim 1, wherein, The chemical composition of the Al2O3 particles comprises any one or a combination of at least two of ɑ-Al2O3, β-Al2O3 or γ-Al2O3.

11. The composite solid-state electrolyte material of claim 10, wherein, The chemical composition of the Al2O3 particles is ɑ-Al2O3.

12. The composite solid-state electrolyte material of claim 1, wherein, The particle size D50 of the Al2O3 particles is 1-50 μm.

13. The composite solid-state electrolyte material of claim 12, wherein, The Al2O3 particles are ɑ-Al2O3 with a particle size D50 of 2-10 μm.

14. The method of claim 1-13, wherein the composite solid-state electrolyte material is prepared by, The method comprises the following steps: (1) A ceramic matrix green body is prepared by a forming process using electrolyte powder. (2) A slurry containing Al2O3 is prepared, and the slurry is coated onto the surface of the ceramic matrix green body in step (1) by a coating process to form an Al2O3 layer. (3) A slurry containing lithium salt is prepared, and a lithium salt layer is formed on the surface of the Al2O3 layer in step (2) by a spraying process. (4) Sintering is performed to obtain a composite solid-state electrolyte material.

15. The method of claim 14, wherein, The forming process in step (1) comprises any one of cold isostatic pressing, tape casting or calendering.

16. The method of claim 15, wherein, The forming process in step (1) is cold isostatic pressing.

17. The method of claim 16, wherein, The cold isostatic pressing method is used to prepare the ceramic matrix green body in step (1), and the pressure for tabletting is controlled to be 50-150 MPa.

18. The method of claim 14, wherein, The D50 of the electrolyte powder in step (1) is 0.1-10 μm, and the D90 is 0.2-20 μm.

19. The method of claim 16, wherein, The cold isostatic pressing method is used to prepare the ceramic matrix green body in step (1), and the prepared ceramic matrix green body has a diameter of 2-15 mm and a thickness of 1-5 mm.

20. The method of claim 14, wherein, The ceramic matrix green body in step (1) is a solid-state fast ionic ceramic matrix green body.

21. The method of claim 14, wherein, The Al2O3 in step (2) comprises any one or a combination of at least two of ɑ-Al2O3, β-Al2O3 or γ-Al2O3.

22. The method of claim 21, wherein, The Al2O3 in step (2) is ɑ-Al2O3.

23. The method of claim 14, wherein, The particle size D50 of the Al2O3 in step (2) is 1-50 μm.

24. The method of claim 23, wherein, The particle size D50 of the Al2O3 in step (2) is 1-2 μm.

25. The method of claim 24, wherein, The Al2O3 in step (2) is ɑ-Al2O3 with a particle size D50 of 1-2 μm.

26. The method of claim 14, wherein, The particle size of the Al2O3 in step (2) is smaller than that of the electrolyte powder.

27. The method of claim 14, wherein, The solvent used in the slurry preparation of step (2) includes any one or a combination of at least two of deionized water, methanol, ethanol, isopropanol, acetone, butanone, or trichloroethylene.

28. The method of claim 27, wherein, The solvent used in the slurry preparation of step (2) is deionized water.

29. The method of claim 14, wherein, The thickness of the Al2O3 layer prepared by coating in step (2) is 1-8 μm.

30. The method of claim 29, wherein, The thickness of the Al2O3 layer prepared by coating in step (2) is 1-5 μm.

31. The method of claim 14, wherein, The dispersant used in the slurry preparation of step (2) includes any one or a combination of at least two of polyethylene glycol, polymethacrylic acid, polyacrylic acid, acrylic acid-acrylate copolymer, or polyvinylpyrrolidone.

32. The method of claim 31, wherein, The content of the dispersant is 0.5-10 wt.% based on the total mass of the slurry of step (2) as 100 wt.%.

33. The method of claim 32, wherein, The content of the dispersant is 2-6 wt.% based on the total mass of the slurry of step (2) as 100 wt.%.

34. The method of claim 14, wherein, The solid content of the slurry of step (2) is 5-30%.

35. The method of claim 34, wherein, The solid content of the slurry of step (2) is 10-15%.

36. The method of claim 14, wherein, The lithium salt of step (3) includes any one or a combination of at least two of lithium carbonate, lithium nitrate, lithium oxalate, lithium acetate, or lithium citrate.

37. The method of claim 14, wherein, The solvent used in the slurry preparation of step (3) includes any one or a combination of at least two of deionized water, methanol, ethanol, isopropanol, or butanone.

38. The method of claim 37, wherein, The solvent used in the slurry preparation of step (3) is acetone.

39. The method of claim 14, wherein, The dispersant used in the slurry preparation of step (3) includes any one or a combination of at least two of polyethylene glycol, polymethacrylic acid, polyacrylic acid, acrylic acid-acrylate copolymer, or polyvinylpyrrolidone.

40. The method of claim 39, wherein, The content of the dispersant is 0.5-8 wt.% based on the total mass of the slurry of step (3) as 100 wt.%.

41. The method of claim 40, wherein, The content of the dispersant is 3-5 wt.% based on the total mass of the slurry of step (3) as 100 wt.%.

42. The method of claim 14, wherein, The solid content of the slurry of step (3) is 0.1-50%.

43. The method of claim 42, wherein, The solid content of the slurry of step (3) is 5-13%.

44. The method of claim 14, wherein, The thickness of the lithium salt layer of step (3) is 1-3 μm.

45. The method of claim 44, wherein, The thickness of the lithium salt layer of step (3) is 1-2 μm.

46. The method of claim 14, wherein, The device used in the sintering of step (4) includes any one or a combination of at least two of a muffle furnace, a tube furnace, a box furnace, or a rotary furnace.

47. The method of claim 14, wherein, The temperature of the sintering of step (4) is 600-900 °C.

48. The method of claim 14, wherein, The time of the sintering of step (4) is 3-12 h.

49. The method of claim 14, wherein, The heating rate for heating to the temperature of the sintering is 1-10 °C / min.

50. The method of claim 14, wherein, The atmosphere of the sintering of step (4) includes any one or a combination of at least two of air, oxygen, nitrogen, helium, or neon.

51. The method of claim 14, wherein, The method further includes a step of drying after step (3) and before step (4).

52. The method of claim 14, wherein, The method includes the following steps: (1) preparing a PVA aqueous solution, adding electrolyte powder, grinding, and pressing the ground electrolyte powder into a ceramic matrix green body under a pressure of 50-150 MPa by cold isostatic pressing; (2) using polyacrylic acid as dispersant, preparing an aqueous solution, taking D50 of 1-2 μm α-Al2O3 in the aqueous solution, preparing a slurry with solid content of 10-30%, using ammonia to adjust the pH value of the solution to 8-9, using the prepared slurry to coat the surface of the ceramic body prepared in step (1) by coating method; (3) using lithium salt, dispersant and acetone, preparing a slurry with solid content of 5-13%, wherein the dispersant is polyacrylic acid, and the content of the dispersant accounts for 1 wt.% of the slurry, using the prepared slurry to spray on the α-Al2O3 coating layer prepared in step (2) by spray gun, forming a layer of lithium salt on the surface of α-Al2O3; (4) sintering the composite electrolyte prepared in step (3) at 600-900 ℃ for 3-12 h, forming a composite layer of α-Al2O3 and LiAlO2 on the surface of the ceramic electrolyte, thereby preparing a composite solid-state electrolyte material.

53. A lithium-ion battery, characterized by, The lithium ion battery comprises the composite solid-state electrolyte material according to any one of claims 1-13.

54. The lithium-ion battery of claim 53, wherein, The lithium ion battery is a lithium ion full solid-state battery.

55. The lithium-ion battery of claim 53, wherein, The lithium ion battery uses metal lithium as the negative electrode.

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