Method for interface modification of sulfur-containing solid electrolyte

Abstract

The invention provides a method for interface modification of a sulfur-containing solid electrolyte. The method comprises the following steps: (S1) applying pressure to the sulfur-containing solid electrolyte and metal aluminum in a mold, and pressing the sulfur-containing solid electrolyte and the metal aluminum into a whole; (S2) sintering the integrally pressed mixture in an inert atmosphere at 270-310 DEG C, and naturally cooling to room temperature to obtain a solid electrolyte precursor; (S3) assembling the lithium battery with the solid electrolyte precursor, the positive electrode and the negative electrode, wherein one surface of the solid electrolyte precursor, which is integrally pressed with aluminum, is at the negative electrode end; when the negative electrode is aluminum, the aluminum on the surface of the solid electrolyte precursor does not need to be stripped off; when the negative electrode is not aluminum, aluminum on the surface of the solid electrolyte precursor is stripped off; and (S4) circulation is carried out under a low-rate condition, a coexistence layer of Li9Al4 and P2S74-is formed on the interface, and interface modification of the sulfur-containing solid electrolyte is completed. According to the modification method, the interfacial ionic conductivity is improved, the solid electrolyte / negative electrode interface side reaction is reduced, the pressure change rate of the all-solid-state battery is reduced, and the cycle life of the all-solid-state battery is effectively prolonged.

Description

Technical Field

[0001] This invention belongs to the field of solid electrolytes, and specifically relates to a method for modifying the interface of sulfur-containing solid electrolytes. Background Technology

[0002] All-solid-state lithium metal batteries have attracted widespread attention from researchers due to their high energy density and efficiency. Using non-flammable solid electrolytes with high mechanical modulus instead of traditional liquid electrolytes is believed to suppress lithium dendrite formation and improve battery safety. Currently widely used solid electrolytes often undergo chemical side reactions with the negative electrode during cycling and are susceptible to electron attack, generating side reaction products at the negative electrode interface and thus degrading battery performance. Furthermore, all-solid-state batteries require external pressure to operate normally; however, large stress changes during operation can easily induce mechanical failures at the battery interface, such as pore formation and electrode desorption, leading to battery failure over long cycles. In addition, the slow lithium-ion diffusion kinetics at the electrode interface is also a factor limiting the performance of all-solid-state batteries. Currently, researchers assemble all-solid-state batteries with a common sulfide solid electrolyte on the negative electrode side and a halide solid electrolyte on the positive electrode side. Due to the special positive electrode-electrolyte hybrid preparation method on the positive electrode side, its interfacial ion transport is better, and the intrinsic volume expansion of the positive electrode is small, resulting in less stress failure. Therefore, modification of the sulfide negative electrode interface is particularly important. However, due to the wide variety of sulfide solid electrolytes, different interface modification strategies need to be customized for different characteristics of sulfide solid electrolytes, making it difficult to achieve universality. Summary of the Invention

[0003] To address the aforementioned problems, the purpose of this invention is to provide a method for modifying the interface of a sulfur-containing solid electrolyte, and to improve the electrochemical performance of all-solid-state batteries using the modified solid electrolyte. This invention is adaptable to sulfur-containing solid electrolytes, reduces electrolyte side reactions, slows down the stress change rate of all-solid-state batteries, reduces battery overpotential, and significantly improves battery cycle life. This invention uses a co-sintering reaction between a sulfide electrolyte and metallic aluminum to create an aluminum sulfide interface buffer layer on the negative electrode side of the sulfide solid electrolyte. Interface modification reduces electrolyte side reactions, slows down the stress change rate of all-solid-state batteries, reduces battery overpotential, and significantly improves battery cycle life. The sulfide solid electrolyte does not chemically react with aluminum metal at room temperature. The aluminum surface oxide layer is very dense and stable. In close contact with aluminum metal, the sulfide solid electrolyte produces an aluminum sulfide phase at high temperatures. This phase can be electrochemically lithiated to form a high-lithium-content lithium-aluminum alloy and aluminum sulfide. The lithium-aluminum alloy has high ion diffusion conductivity, and the coexistence layer with lithium sulfide reduces side reactions of the sulfide solid electrolyte, lowering the overall stress change rate of the all-solid-state battery. Specifically, the present invention provides the following technical solutions to achieve the above objectives:

[0004] A method for modifying the interface of a sulfur-containing solid electrolyte includes the following steps:

[0005] (S1) A sulfur-containing solid electrolyte and metallic aluminum are pressed together in a mold under pressure;

[0006] (S2) The mixture, which is pressed into a single piece, is sintered at 270-310℃ under an inert atmosphere and naturally cooled to room temperature to obtain a solid electrolyte precursor.

[0007] (S3) The solid electrolyte precursor, positive electrode, and negative electrode are assembled into a lithium battery. The side of the solid electrolyte precursor that is pressed together with aluminum is at the negative electrode. When the negative electrode is aluminum, it is not necessary to peel off the aluminum on the surface of the solid electrolyte precursor. When the negative electrode is not aluminum, the aluminum on the surface of the solid electrolyte precursor is peeled off.

[0008] (S4) Cycling is performed under low-rate conditions to form Li9Al4 and P2S7 at the interface. 4- The coexistence layer completes the interface modification of sulfur-containing solid electrolytes.

[0009] Further, in step (S1), the ionic conductivity of the sulfur-containing solid electrolyte is >1 mS / cm, specifically selected from Li2GeS3, Li4GeS4, Li2ZnGeS4, and Li 4-2x Zn x GeS4(0≤x≤1), Li5GaS4, Li 4+x+y (Ge 1-y-x Ga x )S4(0≤x≤0.2, 0≤y≤1), Li 10 GeP2S 12 O x F y (0≤x≤1,0≤y≤1), Li 11-x M 2-x P 1+x S 12 (M = Ge, Sn or Si, 0 ≤ x ≤ 2, e.g., Li) 10 GeP2S 12 ); xLi2S·(100–x)P2S5, Li6PS5X (X=Cl, Br or I).

[0010] Preferably, the sulfur- and phosphorus-containing solid electrolyte is Li6PS5X, such as Li6PS5Cl or Li6PS5Br.

[0011] Sulfur- and phosphorus-containing solid electrolytes can also be composites of sulfur- and phosphorus-containing solid electrolytes with other non-sulfur- and phosphorus-containing solid electrolytes, such as sulfide solid electrolyte-halide solid electrolyte composites, sulfide solid electrolyte-oxide solid electrolyte composites, and sulfide solid electrolyte-polymer composites.

[0012] Further, in step (S1), the aluminum is selected from at least one of aluminum foil, aluminum powder, and aluminum block; it can also be aluminum with a functional modification layer on the surface, the functional modification layer being selected from aluminum fluoride and aluminum chloride; the functional modification layer is prepared by chemical reaction, hot evaporation, and heating evaporation treatment methods.

[0013] Furthermore, in step (S1), the amount of sulfur- and phosphorus-containing solid electrolyte and metallic aluminum used is such that the sulfur- and phosphorus-containing solid electrolyte layer is 400-600 μm thick and the aluminum layer is 20-30 μm thick.

[0014] Furthermore, in step (S2), the inert atmosphere is nitrogen and / or argon, and the sintering temperature is 260-300℃. Sintering is performed by heating to the sintering temperature within 10-30 minutes and holding at that temperature for 0.5-2 hours.

[0015] Further, in step (S3), the positive electrode is selected from lithium cobalt oxide, lithium iron phosphate, ternary positive electrode materials (such as NCM811, NCM622, NCM721, NCM333, NCM523, etc.); the negative electrode is selected from at least one of lithium metal negative electrode, graphite negative electrode, silicon negative electrode, silicon-carbon composite negative electrode, aluminum negative electrode, indium negative electrode, and magnesium negative electrode; after the negative electrode, solid electrolyte precursor, and positive electrode are assembled, a pressure of 1-5 tons is applied and maintained for 1-5 minutes.

[0016] Further, in step (S4), the low rate is 0.01C-0.1C. During the cycling process at the low rate, the aluminum sulfide generated on the negative electrode side of the solid electrolyte will be lithiated in situ during the first charge to form a lithium-rich lithium-aluminum alloy; preferably, the lithium-rich lithium-aluminum alloy is Li9Al4.

[0017] Following the above modification method, aluminum and sulfur-containing solid electrolyte are first pressed together, then sintered at an appropriate temperature. The co-sintered aluminum sulfide is formed at the interface, exhibiting the P2S7 composition. 4- The composition is as follows. It is speculated that Al and LPSCl react at 300℃, reducing sulfur to P2S7. 4- Aluminum is converted into aluminum sulfide. Among them, P2S7... 4-It is a good conductor of lithium; during subsequent low-rate charge-discharge cycles, aluminum sulfide generated on the negative electrode side of the solid electrolyte during the first charge cycle undergoes in-situ lithiation to form lithium-rich lithium aluminum alloys, such as Li9Al4. Li9Al4 also acts as a good conductor of lithium, remaining stable at the interface throughout subsequent cycles and continuing to function as a good conductor of lithium. Furthermore, the introduction of Li9Al4 and P2S7 at the interface... 4- Subsequently, the charge transfer kinetics in the electrochemical reaction at the negative electrode interface are accelerated. This manifests as a decrease in impedance and a reduction in the electrochemical reaction voltage difference. Furthermore, interfacial side reactions are also mitigated due to the introduction of Li9Al4 and P2S7 at the interface. 4- The effect is reduced. This is because co-sintering improves charge transfer, lowers the charge / discharge overpotential, and thus suppresses interfacial side reactions.

[0018] Mechanical failures are increasingly attracting attention due to their significant impact on the performance and lifespan of all-solid-state batteries. These batteries operate under high external pressures, and significant changes in internal stress can lead to mechanical failures, resulting in shortened cycle life and poor solid-solid contact. Mitigating the mechanochemical failures of all-solid-state batteries is crucial for improving their long-term cycling performance. After modification, the generation of mechanical cracks during cycling was also reduced. Furthermore, the battery stress variation decreased, and the electrode volume expansion rate decreased. This can be attributed to Li... + It exhibits rapid conduction and more stable interfacial chemistry.

[0019] The above-mentioned Li9Al4, P2S7 4- The coexistence layer enhances interfacial ionic conductivity, reduces side reactions, and minimizes stress variations during all-solid-state battery operation. It also effectively lowers the lithium-ion interface migration barrier, reduces overpotential, and significantly improves cycle life. Compared to various interface modification methods currently under extensive research, this co-sintering interface modification is universally applicable to sulfide electrolytes, simple to operate, and low in cost. It has broad research potential and promising prospects. Attached Figure Description

[0020] Figure 1 This is a schematic diagram illustrating the principle of improving the interfacial ionic conductivity of solid-state batteries through solid electrolyte interface modification according to the present invention.

[0021] Figure 2 The Raman spectra of the electrolytes in Example 1 and Comparative Example 1 are shown.

[0022] Figure 3 XPS spectra of Al 2p were obtained for the electrolyte of Example 1.

[0023] Figure 4 XPS spectra of the S2p of the electrolytes of Example 1 and Comparative Example 1.

[0024] Figure 5The pressure change rate of the electrolytes in Example 1 and Comparative Example 1 is denoted as .

[0025] Figure 6 Half-cell cycle performance of Example 1 and Comparative Example 1.

[0026] Figure 7 The full-cell cycle performance of Example 1 and Comparative Example 1 is shown.

[0027] Figure 8 The AFM plots and volume change rates are for Example 2 and Comparative Example 6.

[0028] Figure 9 Comparison of Al-Li lithiation overpotentials at different co-sintering temperatures. Detailed Implementation

[0029] The present invention will be further described below with reference to specific embodiments, but the present invention is not limited to the following embodiments. Unless otherwise specified, the experimental methods described in the following embodiments are conventional methods; the reagents and materials described are commercially available unless otherwise specified. Specific embodiments are provided below to help understand the solid electrolyte interface modification strategy described in this invention.

[0030] Example 1

[0031] The LPSCl solid electrolyte interface modification is as follows:

[0032] (S1) The sulfide solid electrolyte is Li6PS5Cl (LPSCl), with a lithium-ion conductivity >1 mS / cm and a high-purity aluminum foil sample with a purity >99.99% at 20 μm. The aluminum foil is introduced into a mold, and then 80 mg of LPSCl is introduced on top of the aluminum foil. It is first flattened with a metal rod, and then a pressure of 3 tons is applied under a press and held for 5 minutes to form an Al-LPSCl composite substrate with an LPSCl layer thickness of 500 μm.

[0033] (S2) Place the mold inside a high-temperature furnace within a glove box. Under argon atmosphere, raise the temperature to 300°C within 10 minutes and hold for 30 minutes. Allow it to cool naturally to room temperature under argon atmosphere. At this point, the disc can be naturally detached from the mold, yielding a solid electrolyte precursor.

[0034] The solid electrolyte precursor wafer was carefully removed, and the surface aluminum was peeled off for Raman characterization. (See results below) Figure 2 The composition of aluminum sulfide is formed by co-sintering on the surface and exhibits P2S7. 4- The composition is as follows. It is speculated that aluminum and LPSCl react at 300℃, reducing sulfur to P2S7. 4- Aluminum transforms into aluminum sulfide.

[0035] (S3) The solid electrolyte precursor is loaded into the solid-state battery mold, high-purity aluminum is added to the negative electrode side, and Li is added to the positive electrode side. 0.8 An In alloy sheet is subjected to a force of 3 tons and held at pressure to form a half-cell.

[0036] (S4) Construct a half-cell according to S1 to S3 above, the difference being that in step S2, the sintering temperature was changed from 300℃ to 230℃ (using the co-sintering temperature of 230℃ as Comparative Example 1), 250℃, 270℃, 290℃, and 310℃ respectively, and discharged to -0.6V at a current of 0.45mA. The overpotential was determined by the peak value of the electrochemical curve. The results are shown in Table 1 and... Figure 9 As shown.

[0037] Table 1. Overpotential magnitudes at different co-sintering temperatures

[0038]

[0039]

[0040] This indicates that different co-sintering temperatures have a significant impact on the overpotential. The overpotential is lowest at 300℃, indicating the existence of an optimal co-sintering temperature range, namely 270-310℃, with 300-310℃ being the preferred range. When the co-sintering temperature is below 270℃, the overpotential rises rapidly, which is detrimental to the performance of the battery's electrochemical properties.

[0041] (S5) Discharge to -0.6V at 0.45mA, then disconnect the battery to strip the aluminum electrolyte, and perform an XPS test on the Al 2p of the electrolyte (see results). Figure 3 Peak separation revealed the surface composition of Li9Al4, indicating the coexistence of LiAl and Li9Al4. LiAl, a typical product of Al lithiation, demonstrates the normal discharge of the assembled battery and confirms that the presence of Li9Al4 does not hinder the normal lithiation of the aluminum anode. XPS analysis of the electrolyte's S2p ​​phase (results are shown in...) Figure 4 By peak segmentation, the surface electrolyte byproduct component Li2S can be analyzed. As a typical sulfide electrolyte byproduct, it can be compared with the intrinsic electrolyte PS4. 3- The peak intensity can be used to analyze the Li₂S content. Comparing Comparative Example 1 (co-sintering temperature 230℃) and Example 1 (co-sintering temperature 300℃), the Li₂S content decreased after discharge in Example 1, indicating that the co-sintering temperature of 300℃ reduced the side reactions of the solid electrolyte. However, the electrolyte co-sintered at 230℃ produced more Li₂S and exhibited more side reactions after discharge. Without co-sintering, the side reactions were severe.

[0042] (S6) After preparing the solid electrolyte precursor according to the methods described in steps S1 to S2 above, reload it into the solid mold, add high-purity aluminum to the negative electrode side, and add 7 mg / cm³ aluminum to the positive electrode side. 2 Lithium cobalt oxide was subjected to a pressure of 1.5 tons and held at that pressure to form a full cell. The cells were cycled at 0.1C, and pressure changes during cycling were monitored using a pressure sensing device. Comparing Example 1 and Comparative Example 1, Example 1 showed smaller pressure changes, which remained at a lower level during long-term cycling. Figure 5 ).

[0043] (S7) After preparing the solid electrolyte precursor according to the methods described in steps S1 to S2 above, reload it into the solid mold, add high-purity aluminum to the negative electrode side, and add Li to the positive electrode side. 0.8 In alloy sheet. A long-cycle test was conducted at 0.5C current with a force of 3 tons and a holding pressure (here, current density does not affect Li9Al4 formation, as long as the external circuit provides electrons). The half-cell of Example 1 showed superior performance, with approximately twice the discharge capacity at high rates. The retention rate after 200 cycles was 75%, twice that of Comparative Example 1. Figure 6 ).

[0044] (S8) After preparing the solid electrolyte precursor according to the methods described in steps S1 to S2 above, reload it into the solid mold, add high-purity aluminum to the negative electrode side, and add 21 mg / cm³ aluminum to the positive electrode side. 2 Lithium cobalt oxide was subjected to a pressure of 1.5 tons and held at that pressure. Example 1, compared to Comparative Example 1, exhibited superior electrochemical performance, showing a significantly improved capacity retention of 90.2% after 420 cycles at 0.25C rate. Figure 7 However, Comparative Example 1 failed after 180 laps and could not demonstrate capacity.

[0045] Examples 2-4

[0046] Examples 2-4 and Comparative Examples 2-4 compared the volume expansion rates of different sulfide electrolyte-Al metal interfaces during cycling using co-sintering modification strategies. Specific electrolyte types, chemical formulas, and quantitative values ​​of volume change rates are shown in Table 2. Atomic force microscopy images of Examples 2 and Comparative Examples 2 are shown below. Figure 9 .

[0047] Preparation and testing steps for samples used in volume expansion rate testing:

[0048] Step 1: Weigh 80 mg of sulfide solid electrolyte in an argon-gated glove box and pour it into a solid-state battery mold. Then apply a pressure of 3 tons and hold for 5 minutes to press it into a powder cake. The powder cake thickness is 500 μm at this point.

[0049] Step 2: Place the powder cake into a thermal evaporation system in a nitrogen-environment glove box, and place 99.999% high-purity aluminum particles into a tungsten boat.

[0050] Step 3: To facilitate the measurement of volume change rate using AFM, a thin-film electrode is first prepared using thermal evaporation. The thermal evaporation chamber is evacuated to a vacuum level of 5*10. -6 An 80nm aluminum layer was deposited on the powder cake at 25% power and a rate of 0.5 Å / s using mbar. This was chosen because the 80nm aluminum layer had high flatness, making it easier to test the volume change rate, as the volume expansion was subsequently measured using AFM.

[0051] Step 4: Divide the above-mentioned sulfide solid electrolyte with aluminum layer into two batches in an argon glove box. One batch is heated to 300°C in the glove box furnace for 10 minutes, kept at that temperature for 30 minutes, and then naturally cooled to room temperature before being taken out.

[0052] Step 5: Press the other end (without aluminum layer) of the above-mentioned powder cake (co-sintered) into a lithium sheet and transfer it to an atomic force microscope for discharge at a current of 3uA (voltage cutoff to 0V), followed by charging with the same current (voltage cutoff to 0.5V). During this process, the morphological changes are measured in situ using an atomic force microscope, and the volume change rate is statistically analyzed.

[0053] 1. The atomic microscope was used in PeakForce Quantitative Nanomechanics mode.

[0054] 2. The selected needle tip parameters are: silicon needle tip elastic modulus = 26 N / m -1 Frequency = 300kHz, tip radius = 10nm.

[0055] 3. Imaging parameters: Scanning speed = 0.977Hz, Scanning range = 20μm × 20μm.

[0056] Comparative Examples 2-4

[0057] Comparative Examples 2-4 show the bonding of pure electrolyte-Al layers without co-sintering. Specific electrolyte types, chemical formulas, and quantitative values ​​of volume change rates are shown in Table 2.

[0058] Preparation and testing details of samples for volume expansion rate testing:

[0059] Step 1: Weigh 80 mg of sulfide solid electrolyte in an argon-gated glove box and pour it into a solid-state battery mold. Then apply 3 tons of pressure and hold for 5 minutes to press it into a powder cake. At this point, the powder cake thickness is 500 μm.

[0060] Step 2: Place the powder cake into a thermal evaporation system in a nitrogen-environment glove box, and place 99.999% high-purity aluminum particles into a tungsten boat.

[0061] Step 3: Evacuate the hot-dip evaporation chamber to 5*10 -6 mbar, at 25% power, at a rate of 0.5 angstroms per second, deposits an 80 nm aluminum layer on the powder cake.

[0062] Step 4: Press the other end (without aluminum layer) of the powder cake (unco-sintered) into a lithium sheet and transfer it to an atomic force microscope for discharge at 3uA (voltage cutoff to 0V), followed by charging with the same current (voltage cutoff to 0.5V). During this process, the morphological changes are measured in situ using an atomic force microscope, and the volume change rate is statistically analyzed.

[0063] 1. The atomic microscope was used in PeakForce Quantitative Nanomechanics mode.

[0064] 2. The selected needle tip parameters are: silicon needle tip elastic modulus = 26 N / m -1 Frequency = 300kHz, tip radius = 10nm.

[0065] 3. Imaging parameters: Scanning speed = 0.977Hz, Scanning range = 20μm × 20μm.

[0066] Table 2 Comparison of electrolyte composition and Al|electrolyte|Li battery volume change rate between Examples 2-4 and Comparative Example 2-4

[0067]

[0068] In summary, the co-sintering solid electrolyte modification strategy proposed in this invention, characterized by high interfacial stability, high ionic conductivity, and low stress variation rate, can be applied to sulfide solid electrolytes. It effectively addresses the problems of low interfacial ionic conductivity and interfacial instability in solid electrolytes, while also effectively solving the problem of excessive stress variation in solid-state batteries. Compared with various modification strategies currently widely studied, the proposed co-sintering modification strategy not only improves interfacial ionic conductivity and reduces interfacial side reactions, but also reduces stress variation, demonstrating broad research potential and application prospects.

Claims

1. A method for modifying the interface of a sulfur-containing solid electrolyte, characterized in that, Includes the following steps: (S1) A sulfur-containing solid electrolyte and metallic aluminum are pressed together in a mold under pressure; (S2) The mixture, which is pressed into a single piece, is sintered at 270-310℃ under an inert atmosphere and naturally cooled to room temperature to obtain a solid electrolyte precursor. (S3) The solid electrolyte precursor, positive electrode, and negative electrode are assembled into a lithium battery. The side of the solid electrolyte precursor that is pressed together with aluminum is at the negative electrode. When the negative electrode is aluminum, it is not necessary to peel off the aluminum on the surface of the solid electrolyte precursor. When the negative electrode is not aluminum, the aluminum on the surface of the solid electrolyte precursor is peeled off. (S4) Cycling is performed under low-rate conditions to form Li9Al4 and P2S7 at the interface. 4- The coexistence layer completes the interface modification of sulfur-containing solid electrolytes.

2. The method according to claim 1, characterized in that, In step (S1), the ionic conductivity of the sulfur-containing solid electrolyte is >1 mS / cm, specifically selected from Li2GeS3, Li4GeS4, Li2ZnGeS4, and Li 4-2x Zn x GeS4(0≤x≤1), Li5GaS4, Li 4+x+y (Ge 1-y-x Ga x )S4(0≤x≤0.2, 0≤y≤1), Li 10 GeP2S 12 O x F y (0≤x≤1,0≤y≤1), Li 11-x M 2-x P 1+x S 12 (M = Ge, Sn or Si, 0 ≤ x ≤ 2, e.g., Li) 10 GeP2S 12 ); xLi2S·(100–x)P2S5, Li6PS5X (X=Cl, Br or I).

3. The method according to claim 1, characterized in that, Sulfur- and phosphorus-containing solid electrolytes are Li6PS5X, such as Li6PS5Cl and Li6PS5Br.

4. The method according to claim 1, characterized in that, In step (S1), the aluminum is selected from at least one of aluminum foil, aluminum powder, and aluminum block; it can also be aluminum with a functional modification layer on the surface, wherein the functional modification layer is selected from aluminum fluoride and aluminum chloride; the functional modification layer is prepared by chemical reaction, hot evaporation, and heating evaporation treatment.

5. The method according to claim 1, characterized in that, In step (S1), the amount of sulfur- and phosphorus-containing solid electrolyte and metallic aluminum used is such that the sulfur- and phosphorus-containing solid electrolyte layer is 400-600 μm thick and the aluminum layer is 20-30 μm thick.

6. The method according to claim 1, characterized in that, In step (S2), the inert atmosphere is nitrogen and / or argon, and the sintering temperature is 260-300℃; sintering is carried out by heating to the sintering temperature within 10-30 minutes and holding at that temperature for 0.5-2 hours.

7. The method according to claim 1, characterized in that, In step (S3), the positive electrode is selected from lithium cobalt oxide, lithium iron phosphate, ternary positive electrode materials (such as NCM811, NCM622, NCM721, NCM333, NCM523, etc.); the negative electrode is selected from at least one of lithium metal negative electrode, graphite negative electrode, silicon negative electrode, silicon-carbon composite negative electrode, aluminum negative electrode, indium negative electrode, and magnesium negative electrode; after the negative electrode, solid electrolyte precursor, and positive electrode are assembled, they are pressurized to 1-5 tons and maintained for 1-5 minutes.

8. The method according to claim 1, characterized in that, In step (S4), the low rate is 0.01C-0.1C. During the cycling process at the low rate, the aluminum sulfide generated on the negative electrode side of the solid electrolyte will be lithiated in situ during the first charge to form a lithium-rich lithium-aluminum alloy.

9. The method according to claim 8, characterized in that, Lithium-rich lithium-aluminum alloys include Li9Al4.

Images