Ceramic soft composites for solid silicon anodes.

Abstract

To provide an anode composite (AC) for forming an anode that is stable over repetitive charge-discharge cycles of a solid-state lithium battery.SOLUTION: An anode composite (AC) for use in a solid-state lithium batteries includes particles of a silicon active material, a carbon additive for electrical conductivity, and a solid electrolyte that combines solid elastic electrolyte (SEE) with a solid non-elastic electrolyte. The solid non-elastic electrolyte is a lithium thiophosphate or other ceramic lithium ion conductor and the SEE includes an ammonium or phosphonium ion closo-borate doped with a lithium salt. The SEE is diffused onto the combined particles uniformly by heating, where pressing achieves about 100% relative density at modest pressures. The anode displays high stability upon charge-discharge cycles of a solid-state lithium battery prepared with the AC layer, appearing to maintain stable intrinsic and extrinsic interfaces.SELECTED DRAWING: Figure 1A

Description

[Technical Field]

[0001] The present disclosure relates generally to electrochemical cells, and more particularly to anodes for solid-state lithium batteries. [Background technology]

[0002] background Advanced solid-state secondary batteries contain a solid electrolyte separator (SE-sep) sandwiched between an anode composite (AC) layer and a cathode composite (Cathode Comp) layer. A typical AC contains carbon, an active material, and a solid electrolyte material. The active material has a high lithium storage capacity. The interface between these AC materials within the AC layer is known as the intrinsic interface. The interface between the outer AC layer and the SE-sep layer is known as the extrinsic interface. Among active materials, silicon is one of the most promising, boasting a high theoretical lithium storage capacity (approximately 10 times that of graphite), a large volume, a low lithiation potential, a low discharge voltage, and a low price. Unfortunately, silicon tends to break down during lithium insertion and deinsertion cycling, which is unfavorable for both the intrinsic and extrinsic interfaces. Summary of the Invention [Problem to be solved by the invention]

[0003] The internal interfacial resistance of the AC layer increases due to mechanical cracking. The resistance of the AC layer increases when the physical contact between the anode active materials, such as solid electrolyte, carbon, and / or silicon, within the AC layer is lost. The external interfacial resistance between AC layers increases when the interfacial contact between the AC layer and the SE-sep layer becomes poor. The mechanical separation of the interface between the SE-sep layer and the AC layer during lithiation and delithiation leads to capacity fade.

[0004] Therefore, it is desirable to achieve more stable AC layers that can overcome the problems associated with interfacial degradation with silicon-containing anodes for solid-state lithium batteries. [Means for solving the problem]

[0005] overview Disclosed in various non-limiting embodiments is a silicon / carbon / solid electrolyte composite anode composite (AC) layer for forming a stable anode during repeated charge-discharge cycling of a solid-state Li battery. The AC solid electrolyte material includes a soft elastic electrolyte (SEE) and a solid inelastic electrolyte. The SEE melts and diffuses around the particles and is uniformly distributed throughout the mixture of silicon particles (active material) and carbon particles (conductive additive) of the AC layer.

[0006] In various non-limiting embodiments, the solid electrolyte material includes a combination of a solid non-elastic electrolyte, which may be lithium thiophosphate (LPS), and an SEE. LPS includes Li3PS4, Li7P3S 11 , Li 10 GeP2S 11 , xLi2S·yP2S5·(100-xy)LiX (X=Cl, Br, and I), where x and y are weight percent values, x and y are both in the range of about 33% to about 50%, and x+y is greater than about 75%, or other solid lithium electrolytes. LPS may be prepared as a milled combination of Li2S and P2S5 and / or GeS2. SEE is an organic cation closoborane anion salt, the organic cation having flexible and / or asymmetric substituents attached to the positively charged nitrogen or phosphorus atom, the closoborane anion being CB 11 H 12 - , CB9H 10 - , or B 12 H 12 -2 , or substitution variants thereof.

[0007] In one embodiment provided herein, the organic cation closo boron cluster salt is prepared by salt metathesis in solution between a metal cation boron cluster salt (typically an alkali or earth alkali cation) and an organic cation salt (typically one having a halide anion). The organic cation closo boron cluster salt is LiCB 11 H 12 or LiCB9H 10 The AC layer is doped with a Li salt, such as 0.1% or 1.2% of silicon, or both. Doping may involve physically mixing the two salts, heating the mixture to a temperature sufficient to at least partially melt the mixture, optionally further mixing, and forming the doped SEE as a solid upon cooling to 25°C. In one embodiment provided herein, the method for preparing the AC layer involves a melt-diffusion process. The AC is constructed by grinding or milling about 20 to about 80 wt. % silicon particles, about 5 to about 30 wt. % carbon particles, and about 20 to about 50 wt. % solid electrolyte (the solid electrolyte being LPS, SEE, or a combination thereof) into a well-dispersed mixture, which is then heated to a temperature sufficient to melt the SEE but not exceed the crystallization temperature of LPS. Melt infusion of the SEE throughout the AC particles can result in a relative density of about 100% and a uniform composition throughout the AC layer when compressed at relatively low pressures of less than 2 tons per square centimeter.

[0008] In one embodiment provided herein, the AC is included as an AC layer in an electrochemical device such as a solid-state lithium battery, along with a cathode layer and a solid electrolyte separator (SE-sep). The SE-sep separates the Li during charging and discharging of the cell. + The cathode may be any solid electrolyte for transporting the cathode. The cathode may be of any structure suitable for use in a solid-state lithium battery.

[0009] These and other features of the solid silicon anode and its preparation will become apparent from a reading of the following detailed description and illustrative, non-limiting figures and examples.

[0010] BRIEF DESCRIPTION OF THE DRAWINGS For a better understanding of the processes and devices having solid silicon anodes with respect to the specific variations and examples described herein, reference is made to the accompanying drawings. [Brief explanation of the drawings]

[0011] [Figure 1A] Figures 1A-1D show scanning electron microscope (SEM) images of the Si-LPS-SEE anode composite (AC) powder (1A) and its pressed pellet (with closoborane anions in the SEE) (1B), as well as boron energy dispersive X-ray (EDS) maps showing the uniform distribution of the SEE in the powder (1C) and pellet (1D) after uniform melt diffusion of the SEE throughout the Si-LPS powder. [Figure 1B] Figures 1A-1D show scanning electron microscope (SEM) images of the Si-LPS-SEE anode composite (AC) powder (1A) and its pressed pellet (with closoborane anions in the SEE) (1B), as well as boron energy dispersive X-ray (EDS) maps showing the uniform distribution of the SEE in the powder (1C) and pellet (1D) after uniform melt diffusion of the SEE throughout the Si-LPS powder. [Figure 1C] Figures 1A-1D show scanning electron microscope (SEM) images of the Si-LPS-SEE anode composite (AC) powder (1A) and its pressed pellet (with closoborane anions in the SEE) (1B), as well as boron energy dispersive X-ray (EDS) maps showing the uniform distribution of the SEE in the powder (1C) and pellet (1D) after uniform melt diffusion of the SEE throughout the Si-LPS powder. [Figure 1D]Figures 1A-1D show scanning electron microscope (SEM) images of the Si-LPS-SEE anode composite (AC) powder (1A) and its pressed pellet (with closoborane anions in the SEE) (1B), as well as boron energy dispersive X-ray (EDS) maps showing the uniform distribution of the SEE in the powder (1C) and pellet (1D) after uniform melt diffusion of the SEE throughout the Si-LPS powder. [Figure 2] 1 is a bar graph showing the relative density of LPS and LPS-SEE pellets pressurized at increasing pressures, where a maximum relative density of approximately 100% is achieved for LPS-SEE at a pressure of approximately 1.5 tons / cm2, while a pressure of 5 tons / cm2 is required to achieve the maximum relative density (less than 100%) for LPS. [Figure 3A] 3A-3C illustrate the construction of a half-cell by (3A) pressing a lithium thiophosphate electrolyte doped with lithium halide, (3B) pressing this electrolyte with an Si-LPS-SEE or Si-LPS anode composite according to one embodiment, and (3C) pressing the electrolyte-anode with a lithium-indium foil cathode. [Figure 3B] 3A-3C illustrate the construction of a half-cell by (3A) pressing a lithium thiophosphate electrolyte doped with lithium halide, (3B) pressing this electrolyte with an Si-LPS-SEE or Si-LPS anode composite according to one embodiment, and (3C) pressing the electrolyte-anode with a lithium-indium foil cathode. [Figure 3C] 3A-3C illustrate the construction of a half-cell by (3A) pressing a lithium thiophosphate electrolyte doped with lithium halide, (3B) pressing this electrolyte with an Si-LPS-SEE or Si-LPS anode composite according to one embodiment, and (3C) pressing the electrolyte-anode with a lithium-indium foil cathode. [Figure 4A]4A-4B show SEM images of one embodiment of Si-LPS-SEE AC (4A) and Si-LPS AC (4B) after individual half-cells were cycled 100 times at 2.0 mA / cm in each half-cell; the squares are positioned over several large cracks in the "hard" Si-LPS AC, which are absent in the "soft" Si-LPS-SEE AC. [Figure 4B] 4A-4B show SEM images of one embodiment of Si-LPS-SEE AC (4A) and Si-LPS AC (4B) after individual half-cells were cycled 100 times at 2.0 mA / cm in each half-cell; the squares are positioned over several large cracks in the "hard" Si-LPS AC, which are absent in the "soft" Si-LPS-SEE AC. [Figure 5] 1 shows a composite plot of discharge capacity and coulombic efficiency retention for half-cells with a "hard" Si-LPS AC and an embodiment of a "soft" Si-LPS-SEE anode composite, where the cycle that caused failure for the Si-LPS AC is indicated by the dashed square. [Figure 6] 1 shows a composite plot of real and hypothetical impedance measured by electrochemical impedance spectroscopy (EIS) before and after 100 cycles for a "hard" Si-LPS AC and an embodiment of a "soft" Si-LPS-SEE AC, demonstrating an approximately 3-fold increase in resistance upon failure of the Si-LPS AC. [Figure 7A] Figures 7A-7C show diagrams of symmetric cells designed to determine the external resistance R3 between the AC layer and the SE-sep layer by the difference in resistance to the internal resistances R4 and R2 of the SE-sep layer of cell (7A), the AC layer of cell (7B), and the symmetric cell (7C). [Figure 7B] Figures 7A-7C show diagrams of symmetric cells designed to determine the external resistance R3 between the AC layer and the SE-sep layer by the difference in resistance to the internal resistances R4 and R2 of the SE-sep layer of cell (7A), the AC layer of cell (7B), and the symmetric cell (7C). [Figure 7C] Figures 7A-7C show diagrams of symmetric cells designed to determine the external resistance R3 between the AC layer and the SE-sep layer by the difference in resistance to the internal resistances R4 and R2 of the SE-sep layer of cell (7A), the AC layer of cell (7B), and the symmetric cell (7C). [Figure 8] 10 is a bar graph of the extrinsic resistance appearing between the AC and SE-sep layers for the interface between the AC and SE-sep layers of a "hard" Si-LPS and "soft" Si-LPS-SEE AC and SE-sep layers according to one embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0012] The drawings described herein above are intended to illustrate examples of the general features of the methods, algorithms, and devices of the present technology for the purpose of describing specific aspects. The drawings may not precisely reflect the features of any aspect and are not necessarily intended to define or limit specific embodiments within the scope of the present technology.

[0013] Detailed Description The present disclosure provides a composite for use as an anode for a lithium battery. The anode composite (AC) is a layer containing silicon powder combined with a carbon additive and a solid electrolyte that combines a soft elastic electrolyte (SEE) and a solid non-elastic electrolyte. The Si-C powder and electrolyte combination is melt-diffused with the SEE to obtain a uniform composition that provides a stable anode. The stable anode shows no evidence of fracture between the internal and external interfaces, as observed in other anode composites without the SEE. The ratio of Si to C and electrolyte can vary from 20 to about 80 wt.% silicon, from about 5 to about 30 wt.% carbon, and from about 20 to about 50 wt.% solid electrolyte.

[0014] The present disclosure provides an anode electrolyte that can be a combination of a solid, non-elastic electrolyte, such as lithium thiophosphate (LPS), and an SEE, which can be an organic cation closoborate anion salt that can be doped with lithium closoborate. The LPS and SEE are combined such that the SEE comprises about 1 to about 50 mole percent of the anode electrolyte. The LPS can be Li3PS4, Li7P3S 11 , Li 10 GeP2S 11 , or xLi2S·yP2S5·(100-xy)LiX (X=Cl, Br, and I), where x and y are mass percent values, x and y are both in the range of about 33% to about 50%, and x+y is greater than about 75%. LPS may be prepared by ball milling or milling designed for the combination of Li2S, P2S5, and GeS2. Alternatively, solution or microwave-assisted methods can be used to form LPS. The solid inelastic electrolyte can be other than LPS, for example, Li 1.3 Al 0.3 Ti 1.7 (PO4)3(LATP), Li 1+x+γ Al x Ti 2-x Si γ P 3-γ O 12 , LiNi 0.6 Co 0.2 Mn 0.2 O2, Li 0.33 La 0.55 TiO3(LLTO), Li 9.54 Si 1.74 P 1.44 S 11.7 Cl 0.3 NASICON-type Li-ion electrolytes such as Li6ZnNb4O 14 The SEE may be a complex of LPS with other bulking agents such as (LZNO). The SEE may be an organic cation closoborane anion salt, where the organic cation has flexible and / or asymmetric substituents attached to the positively charged nitrogen or phosphorus atom, and the closoborane anion is CB 11 H 12 - , CB9H10 - , B 12 H 12 -2 , substitution variants thereof, and combinations thereof.

[0015] The present disclosure provides for the formation of an organic cation closo boron cluster salt by salt metathesis in solution between a metal cation boron cluster salt (typically an alkali or earth alkali cation) and an organic cation salt (typically a halide anion). The organic cation closo boron cluster salt is LiCB 11 H 12 or LiCB9H 10 or both. Doping may involve physically mixing the two salts, heating the mixture to a temperature sufficient to at least partially melt it, and optionally further mixing to form the doped SEE as a solid upon cooling to 25°C. The SEE has an organic cation, which has the structure [(CR 1 R 2 ) n ] w Z(R 3 ) 4-2w + where n is 4 to 6; w is 0 to 2; Z is N or P; and R 3 The groups are independently C1-C8 alkyl or C6-C 10 aryl, unsubstituted or substituted one or more times with fluorine, alkyl, monofluoro to perfluoroalkyl, alkoxy, monofluoro to perfluoroalkoxy, phenyl, monofluoro to perfluorophenyl, phenoxy, or monofluoro to perfluorophenoxy, where any alkyl or alkoxy group is linear, branched, or cyclic; R 1 Groups and R 2 The groups are independently hydrogen, C1-C8 alkyl, C1-C8 alkoxy, C6-C 10 Aryl, or C6-C 10aryloxy, where the carbon is unsubstituted or substituted one or more times with fluorine, alkyl, monofluoro to perfluoroalkyl, alkoxy, monofluoro to perfluoroalkoxy, phenyl, monofluoro to perfluorophenyl, phenoxy, or monofluoro to perfluorophenoxy, and any alkyl or alkoxy group is linear, branched, or cyclic. When w is 0 or 1, R 3 The group may contain at least two different structures, or all R 3 If the groups are the same, R 3 The R group contains a chiral center but is combined with 3 is a racemic mixture. When w is 2, two spiroammonium or phosphonium ions [(CR 1 R 2 ) n ]Z + The ring structures may be different, or the two [(CR 1 R 2 ) n ]Z + If the rings are the same, then at least one CR 1 R 2 R is different 1 Groups and R 2 group, and R 1 Groups and R 2 The groups are randomly positioned on both sides of the structure, for example, randomly positioned at the axial and equatorial positions of the n=5 ring. The Z atom may, but need not, be a chiral center, or R 1 Group, R 2 group, or R 3 Any of the groups may, but need not, be chiral. Multiple different organic cations may be combined with one or more closoborate anions to form organic cation closoborate anion salts. Additional Li closoborate salts may have the same or different closoborate groups as the ammonium or phosphonium closoborate salts of the SEE.

[0016] This disclosure relates to B 12 H 12 -2, C.B. 11 H 12 - 1. CB9H 10 - 1, or one or more of their substituted derivatives, and an organic cation or Li + The substituted derivative closoborate anion has the structure C y B a-y H a-z X z -(2-y) where y is 0 or 1; when y is 0, a is 12, and when y is 1, a is 10 or 12; z is 0 to a; and X is independently halogen, alkyl, alkoxy, aryl, alkylaryl, arylalkyl, and / or aryloxy substituents, where the alkyl groups may be linear, branched, or cyclic, and any of the substituents may be partially or fully halogenated.

[0017] In various embodiments provided herein, a method is presented for forming an AC from a carbon-doped silicon powder, which can be formed by grinding or milling silicon metal with graphite, carbon black, fullerenes, nanotubes, nanopowder, nanofibers, or any form of carbon that can improve the electrical conductivity of the powder. The milling can be any form, including ball milling and jet milling. The milling is carried out until the Si—C particles are less than about 10 μm in size, such as less than about 1 μm, less than 300 nm, or less than about 50 nm. The crystallite size of the particles can be less than about 1 μm, less than 300 nm, less than 100 nm, or less than about 50 nm.

[0018] The LPS and soft organic ammonium or phosphonium cation closoborate anion salt anode electrolyte (LPS is about 50 to about 99 mol % and SEE is doped with lithium closoborate) may be ground or pulverized to a size of less than about 10 μm, less than 1 μm, for example, less than about 300 nm, or less than about 50 nm. The anode electrolyte may then be mixed with Si-C, and the combined powder may be ground or pulverized to form an AC, followed by heating to melt the SEE electrolyte and form a dense AC layer. The inclusion of the "soft" SEE electrolyte allows for the production of a dense AC layer for Li batteries by pressing at a pressure significantly lower than that required to form a dense AC layer without the "soft" SEE electrolyte. For example, 2 tons / cm 2 By using SEE, the formation of a "hard" AC layer without SEE can be achieved at a molding pressure of approximately 5 ton / cm. 2 It is possible to form AC layers that are denser than can be achieved with ultra-dense materials, which have a relative density of about 100% relative to that of a theoretically fully dense material.

[0019] Various aspects of the present disclosure will be further described with reference to the following examples, it being understood that these examples are provided to illustrate specific embodiments of the present disclosure and that they should not be construed as limiting the scope of the disclosure to any particular aspect.

[0020] Example 1 Li2S and P2S5 (3:1 mol:mol) are ball milled under argon at 25 °C for 50 hours to form Li3PS4 (LPS).

[0021] Example 2 Synthesis of SEE: Metathesis preparation of SEE using LiCB 11 H 12 (3.85g) and LiCB9H 10 (3.24g) to 1-butyl-1-methylpyrrolidinium chloride (Pyr 14The mixture was ground with 3.31 g of HCl in a mortar and pestle under argon for 30 minutes to obtain a homogeneous powder, which was then transferred to a stirred vessel and stirred at 160°C for 24 hours.

[0022] Example 3 Comparative Anode Composite (AC) Si-LPS: A combination of Si:LPS:carbon in the ratio of 55:35:10 by weight:weight:weight was ground in a mortar with a pestle under argon at 25° C. for 15 minutes.

[0023] Example 4 Anode Composite (AC) Si-LPS-SEE: LPS and SEE were combined and ground in a mortar with a pestle under argon at 25° C. for 15 minutes. Silicon and carbon were added to the mortar and grinding continued under argon at 25° C. for 15 minutes. The combined and ground AC powders were heated to 120° C. for 30 minutes to distribute the SEE uniformly throughout the mass, followed by cooling to ambient temperature to prepare the AC.

[0024] The AC powder exhibits the morphology shown in Figure 1A, which is essentially maintained upon densification by application of 10 tons of pressure into a 1.128 cm diameter pellet (shown in Figure 1B). EDS analysis of the powder and pellet (shown in Figures 1C and 1D, respectively) indicates a uniform distribution of boron throughout the AC and AC layers.

[0025] Example 5 Relative Density of LPS-SEE Composites: Combined LPS-SEE composite pellets were pressed at various pressures to determine the change in density of the anode material pellets and determine the minimum molding pressure required to obtain dense pellets that were soft enough to tolerate volume expansion and contraction during charge-discharge cycling. The dimensions of the pellets were measured to calculate the relative densities of the LPS and LPS-SEE composites achieved with increasing molding pressure. Figure 2 shows the difference in relative density between the LPS and LPS-SEE composites and the change in relative density with applied pressure. The LPS-SEE composite reaches a higher, nearly constant maximum relative density at a lower applied pressure than the pellets without SEE. This indicates that the LPS-SEE is a softer composite. A softer composite cushions the mechanical stresses imposed by the silicon expanding and contracting during lithiation and delithiation.

[0026] Example 6 Anode Composite Half Cell: As shown in Figures 3A-3C, solid-state cells were fabricated by (3A) pressing solid electrolyte powder into a pellet, (3B) spreading cathode material on the surface of the solid electrolyte and pressing the stack, and (3C) spreading anode material on the other side of the solid electrolyte and pressing the stack a third time. Anode composite / solid electrolyte / lithium indium cells were fabricated in this manner, where (3A) 80-300 mg of lithium halide-doped lithium thiophosphate was cold-pressed into a 1.128 cm diameter pellet using 0.5-10 tons of pressure, (3B) 1-300 mg of Si-LPS or Si-LPS-SEE powder was spread on the solid electrolyte pellet and the stack was pressed using 0.1-6 tons of pressure, and (3C) placing lithium indium foil on the other side of the solid electrolyte and pressing the stack using 0-4 tons of pressure.

[0027] Example 7 Stability of the anode composite: The "softness" provided by the Si-LPS-SEE AC provided robustness not achievable with the Si-LPS AC without OIPC. SEM analysis of the Si-LPS AC pellet (Figure 4B) shows cracking during cycling, whereas no cracking is observed after cycling in the Si-LPS-SEE AC pellet (Figure 4A). Cycling stability was confirmed by changes in capacitance retention and Coulombic efficiency during cycling, as shown in Figure 5. Electrochemical impedance spectroscopy (Figure 6) of the anode composite demonstrated superior stability, revealing the initial cracking of the "hard" Si-LPS AC after approximately 25 cycles, with its ultimate resistance increasing approximately threefold at failure.

[0028] Example 8 Li-Li Symmetric Cell: Symmetric cells with lithium electrode pairs having the structures shown in Figures 7A-7C were constructed to investigate the resistance of the external interface between the AC layer and the contacting separator-SE layer. To isolate the resistance due to the external interface, cells A, B, and C were constructed as shown in Figures 7A-7C, and the sum of the internal resistances due to the SE-sep and AC layers was subtracted from the two external resistances due to the two interfaces between the SE-sep and AC layers. The external interface resistance, R3, is equal to the resistance measured for cell C minus that of cells A and B, divided by 2: R3 = (Cell 7C - Cell 7B - Cell 7A) / 2.

[0029] As shown in Figure 8, the extrinsic resistance obtained between the SE-sep layer and the "soft" Si-LPS-SEE AC layer is significantly smaller, about one-third, than that between the SE-sep layer and the "hard" Si-LPS AC layer.

[0030] The above description is merely exemplary in nature and is not intended to limit the present disclosure or the application or uses of the present disclosure. As used herein, the expression "at least one (one) of A, B, and C" should be interpreted as meaning "A or B or C" using the non-exclusive logic "or." It is understood that the principles of the present disclosure are not altered even if the various steps included in a method are performed in a different order. The disclosure of ranges includes the disclosure of all individual ranges and individual subranges included in the entire range.

[0031] The headings (e.g., "Background" and "Summary") and subheadings used herein are intended only to generally organize topics within the scope of the present disclosure and are not intended to limit the disclosure of the technology or any aspect thereof. The description of multiple embodiments having described features is not intended to exclude other embodiments having additional features or other embodiments incorporating different combinations of the described features.

[0032] As used herein, the terms "comprises" and "includes," and variations thereof, are intended to be non-limiting, and a sequential description or listing of items does not exclude other similar items that may be useful in the devices and methods of the present technology. Similarly, the terms "can" and "may" and variations thereof are intended to be non-limiting, and a description that an embodiment can or may include a particular element or feature does not exclude other embodiments of the present technology that do not include such element or feature.

[0033] The broad teachings of the present disclosure can be embodied in a variety of forms. Thus, while the present disclosure includes specific examples, other modifications will become apparent to those skilled in the art upon studying the specification and the following claims, and the true scope of the present disclosure should not be limited to the specific examples contained therein. Reference herein to an aspect or various aspects means that a specific feature, structure, or characteristic described in connection with an embodiment or a particular system is included in at least one embodiment or aspect. When the phrase "in one aspect" (or variations thereof) appears, it does not necessarily refer to the same aspect or embodiment. It should also be understood that the various method steps described herein do not necessarily have to be performed in the same order as described, and that not every method step is required for every aspect or embodiment.

[0034] The above-described description of the embodiments is provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the present disclosure. Individual elements or features of a specific embodiment are generally not limited to that specific embodiment and, where appropriate, may be interchangeable and used in selected embodiments without specific labeling or description. Furthermore, individual elements or features of a specific embodiment may be modified in various ways. Such modifications should not be considered a departure from the scope of the present disclosure, and all such modifications are intended to be included within the scope of the present disclosure.

[0035] While specific embodiments have been described above, presently unforeseen or unforeseeable alternatives, modifications, variations, improvements, and substantial equivalents may occur to applicants or others skilled in the art. Accordingly, the appended claims, as filed and as amended, are intended to cover all such alternatives, modifications, variations, improvements, and substantial equivalents.

Claims

1. 1. A method for preparing an anode, comprising: combining a plurality of silicon particles, a plurality of carbon particles, and a plurality of solid electrolyte particles to form a combined powder, the solid electrolyte particles comprising a soft elastic electrolyte (SEE) and a solid non-elastic electrolyte; grinding or pulverizing the combined powder to form an anode composite (AC) powder; heating the AC powder to a temperature between the melting point of the SEE and the crystallization temperature of the solid inelastic electrolyte; and pressing the AC powder to form the anode as an AC layer. the SEE is an organic ammonium or phosphonium cation closoborate anion salt; the solid inelastic electrolyte is lithium thiophosphate; The method for preparing an anode, wherein the heating step comprises heating to a temperature higher than the melting temperature of the SEE and lower than the crystallization temperature of the solid inelastic electrolyte.

2. 2. The method for preparing an anode according to claim 1, wherein the silicon particles, the carbon particles, and the solid electrolyte particles have cross-sectional dimensions of 50 to 1,000 nm.

3. The solid inelastic electrolyte may be: Li ３ PS ４ ; Li ７ P ３ S １１ ; Li １０ GeP ２ S １１ ; xLi ２ S.yP ２ S ５ (100-xy)LiX, where X is Cl, Br, or I, x and y are in weight percentages between 30% and 50%, and x+y is greater than 75%; Li ２ S and P ２ S ５ and / or GeS ２ Grinding or crushing combination with; Any combination thereof; and Any of the above solid inelastic electrolytes and Li ６ ZnNb ４ O １４ (LZNO) composite The method for preparing an anode according to claim 1 , comprising at least one of:

4. The SEE is [(CR １ R ２ ) ｎ ] ｗ Z(R ３ ) ４－２ｗ ＋ (In the formula, n is 4 to 6; w is 0 to 2; Z is N or P; R ３ The groups are independently C １ -C ８ Alkyl or C ６ -C １０ aryl, unsubstituted or substituted one or more times with fluorine, alkyl, monofluoro to perfluoroalkyl, alkoxy, monofluoro to perfluoroalkoxy, phenyl, monofluoro to perfluorophenyl, phenoxy, or monofluoro to perfluorophenoxy, where any alkyl or alkoxy group is linear, branched, or cyclic; and R １ Groups and R ２ The groups are independently hydrogen, C １ -C ８ Alkyl, C １ -C ８ Alkoxy, C ６ -C １０ aryl, or C ６ -C １０ aryloxy and unsubstituted or substituted one or more times with fluorine, alkyl, monofluoro to perfluoroalkyl, alkoxy, monofluoro to perfluoroalkoxy, phenyl, monofluoro to perfluorophenyl, phenoxy, or monofluoro to perfluorophenoxy, wherein any alkyl or alkoxy group is linear, branched, or cyclic; and CB １１ H １２ － 、CB ９ H １０ － 、B １２ H １２ －２ 、C ｙ B ａ－ｙ H ａ－ｚ X ｚ －（２－ｙ） (In the formula, y is 0 or 1; When y is 0, a is 12, and when y is 1, a is 10 or 12; z is 0 to a; and X is independently halogen, alkyl, alkoxy, aryl, alkylaryl, arylalkyl, and / or aryloxy substituents, where the alkyl groups may be linear, branched, or cyclic, and any of the substituents may be partially or fully halogenated, or any combination thereof; and The method for preparing an anode according to claim 1 , comprising:

5. The SEE is CB １１ H １２ － , C.B. ９ H １０ － , B １２ H １２ －２ , and C ｙ B ａ－ｙ H ａ－ｚ X ｚ －（２－ｙ） (In the formula, y is 0 or 1; When y is 0, a is 12, and when y is 1, a is 10 or 12; z is 0 to a; and X is independently halogen, alkyl, alkoxy, aryl, alkylaryl, arylalkyl, and / or aryloxy substituents, where the alkyl groups may be linear, branched, or cyclic, and any substituent may be partially or fully halogenated, or any combination thereof.

6. The combining step comprises: mixing the plurality of silicon particles with the plurality of carbon particles to form a silicon-carbon mixture and grinding or pulverizing the silicon-carbon mixture to form a mixture of silicon and carbon particles; mixing the SEE with the solid non-elastic electrolyte to form the plurality of solid electrolyte particles; and mixing the mixture of silicon and carbon particles with the plurality of solid electrolyte particles to form the combined powder.

7. 10. The method of preparing an anode of claim 1, wherein the grinding or crushing step comprises ball milling, jet milling, or grinding in a mortar with a pestle.

Images