Method for converting waste positive electrode into solid-state electrolyte with lithium supplementing function and application
By embedding elements such as Zr and Ta into lithium-rich transition metal oxides, a single-phase metastable solid solution electrolyte was prepared, which solved the problem of insulating residues in traditional lithium replenishment agents, achieved high energy density and stable lithium-ion conduction, and improved the performance of all-solid-state batteries.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- TONGJI UNIV
- Filing Date
- 2026-04-23
- Publication Date
- 2026-07-10
AI Technical Summary
In existing technologies, traditional lithium replenishment agents leave insulating and inert residues after lithium replenishment, and silicon-based all-solid-state batteries have limited energy density. Furthermore, commonly used oxide or sulfide solid electrolytes are electrochemically inactive, leading to a decrease in battery energy density.
By employing the unique non-equilibrium kinetic cutoff effect of Joule burning for rapid heating, elements such as Zr and Ta are embedded into the lattice of lithium-rich transition metal oxides to prepare a single-phase metastable solid solution, which serves as a solid electrolyte with lithium replenishment function. Through transient pulse electrothermal technology, long-range atomic diffusion is restricted to form a fast-ion conductor network with high lithium vacancies.
This technology enables the material to replenish irreversible lithium consumption during the first charge cycle without adding extra inactive weight, and to transform into a solid electrolyte with high lithium-ion conductivity. This improves the battery's energy density and cycle stability, and simplifies the disposal process for waste cathodes.
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Abstract
Description
Technical Field
[0001] This invention belongs to the field of electrolyte technology, specifically relating to a method and application of converting waste positive electrodes into solid electrolytes with lithium replenishment function. Background Technology
[0002] To meet the demands of portable electronic devices, electric vehicles, and large-scale energy storage for high safety and high energy density, the development of all-solid-state lithium batteries (ASSBs) has become an inevitable trend in the industry, replacing flammable organic liquid electrolytes with non-flammable solid electrolytes (SEs). Simultaneously, to achieve truly high safety performance, the metallic lithium anode of solid-state batteries needs to be replaced with a silicon-based anode. However, during the first charge-discharge cycle, the silicon-based anode experiences significant irreversible active lithium consumption due to volume expansion and the formation of a solid electrolyte interphase (SEI) film, necessitating the introduction of additional active lithium through lithium replenishment technology to compensate for this loss.
[0003] Compared to negative electrode lithium replenishment technology, positive electrode lithium replenishment technology has higher process compatibility and practicality because it can be added directly during the preparation of the positive electrode slurry (CN110854382B, CN115347253B). However, currently common positive electrode lithium replenishment additives have many limitations. For example, although lithium-rich compounds such as lithium oxalate and lithium oxide can release lithium ions, their decomposition potential is too high, close to the oxidation decomposition potential of the electrolyte; while compounds such as lithium-rich lithium iron oxide (Li5FeO4) and lithium-rich lithium cobalt oxide (Li6CoO4), although having moderate decomposition potentials and high lithium replenishment capacity, after complete delithiation in the first cycle, they will transform into electrochemically inert transition metal oxide residues (CN115719808B). In subsequent battery cycles, they not only do not contribute any capacity but also become physical barriers that block electron and ion transport.
[0004] On the other hand, in current solid-state battery designs, a large amount of solid electrolyte powder must be mixed into the positive electrode to construct a composite positive electrode, thereby ensuring the Li + Effective lithium conduction is possible. However, unfortunately, commonly used oxide or sulfide solid electrolytes are completely electrochemically inactive (CN113135736B, CN120341351B). These additional electrolytes only serve to conduct lithium but do not contribute any capacity. This not only significantly dilutes the proportion of active material in the electrode but also severely weakens the core advantage of solid-state batteries in terms of energy density.
[0005] To address the aforementioned pain points, if a bifunctional material could be designed that can act as a high-capacity lithium replenisher to release a large amount of active lithium in the first cycle, and then, after delithiation, transform in situ into a material with high Li- content... +Solid electrolytes with high conductivity. In this way, the delithiation residue will be transformed from "insulating dead weight" into "active ionic conductors" in the cathode of solid-state batteries, thus achieving the dual purpose of lithium replenishment and lithium conduction at the cathode interface without adding extra inactive weight. In addition, if a large amount of retired cathode materials such as lithium cobalt oxide (LCO) can be directly converted into such high-value-added materials as raw materials, it will have important practical significance in terms of economy and environmental protection. Summary of the Invention
[0006] This invention primarily provides a method for preparing a solid electrolyte material with lithium replenishment function by utilizing the unique non-equilibrium kinetic cutoff effect of Joule burning for rapid heating, embedding elements such as Zr and Ta into the crystal lattice of a lithium-rich transition metal oxide lithium replenishment material. This method yields a single-phase metastable solid solution that cannot be thermodynamically synthesized at room temperature and pressure, forming a solid electrolyte material that also possesses lithium replenishment function. This addresses the problems of residual insulating inertness after lithium replenishment and the limited energy density of silicon-based all-solid-state batteries in existing technologies. The technical solution is as follows:
[0007] A solid electrolyte with lithium replenishment function, wherein the solid electrolyte is a single-phase metastable solid solution; the general chemical formula is Li. (6-a) TM (1-x) M x O (4-b) ;
[0008] Wherein, TM is a transition metal element, including one or more of cobalt, nickel, manganese or iron; M is a metal dopant element, including one or more of zirconium, tantalum, niobium, titanium, tungsten, molybdenum or hafnium, and 0.05≤x≤0.4; a and b are lattice defect coefficients caused by the influence of the valence state of the doped metal, satisfying 0≤a≤1 and 0≤b≤1.
[0009] Furthermore, the single-phase metastable solid solution has an antifluorite structure or a cationic disordered rock salt crystal structure; the metal dopant element M uniformly dissolves in the crystal lattice by substituting some TM sites in situ; and there are no independent M element oxides or M-containing impurity phases inside the solid electrolyte. The transition metal element TM has a +2 valence and acts as an active element for lithium replenishment; the metal dopant element M is a framework element used to stabilize the crystal structure.
[0010] Furthermore, the room temperature solid-state lithium-ion conductivity of the solid electrolyte is not less than 1.0 × 10⁻⁶. -4 S / cm.
[0011] Furthermore, the material can irreversibly release a portion of active lithium during the first charge cycle of the battery, thereby replenishing the irreversible lithium consumption of the full battery.
[0012] After releasing active lithium ions during the first charge cycle of a lithium-ion battery, the lattice of this material does not collapse; instead, it transforms in situ into a three-dimensional open fast-ion conductor network, Li, with a high concentration of lithium vacancies. y TM (1-x) M x O (4-c) (where y≤2, c≥2), exists in the electrode plate in the form of a solid electrolyte and provides a continuous lithium-ion conduction channel.
[0013] A method for converting waste cathodes into the aforementioned solid electrolyte with lithium replenishment function includes the following steps:
[0014] a. The recovered cathode powder containing transition metal, lithium source, reducing carbon source and precursor compound of metal dopant element M are mixed uniformly according to the target stoichiometric ratio to obtain a solid-phase mixed precursor.
[0015] b. In an oxygen-free environment, the solid-phase mixed precursor is subjected to a transient high-current pulse for rapid heating, which triggers transient carbothermic reduction and atomic rearrangement reaction;
[0016] c. After reaching the set ultra-high transient peak temperature and holding it at that temperature for an extremely short time, the current pulse is instantly cut off, allowing the reaction system to be rapidly cooled at room temperature. This interrupts the long-range thermodynamic diffusion of atoms, forcing the M element to be kinetically trapped in a lithium-rich transition metal lattice, thus obtaining the desired result.
[0017] Furthermore, the lithium source includes one or more of Li2O, LiOH, Li2CO3, Li2O2 or lithium acetate; the precursor compound of the metal dopant element M has an average particle size of 10~200 nm.
[0018] Furthermore, the oxygen-free environment is a vacuum or an atmosphere of high-purity argon, nitrogen, or helium.
[0019] Furthermore, the reducing carbon source includes one or more of the following: micronized graphite, carbon black, graphene, multi-walled carbon nanotubes, sucrose, glucose, or starch.
[0020] Furthermore, the rapid heating rate is 1000~20000℃ / s; the ultra-high transient peak temperature is 1000~2800℃, and the holding time is 5~60 s.
[0021] Furthermore, the rapid cooling rate is not less than 1000 K / s.
[0022] Furthermore, the cathode powder containing transition metals obtained in step a is not subjected to leaching for purification, and the original conductive agent and binder are retained.
[0023] Application of the above-mentioned solid electrolyte with lithium replenishment function in the preparation of all-solid-state batteries or solid-liquid hybrid batteries.
[0024] Furthermore, a solid electrolyte is added to the positive electrode of an all-solid-state battery or a solid-liquid hybrid battery at a mass of 5-30% of the total positive electrode active material, serving as an active solid electrolyte. This solid electrolyte achieves efficient lithium replenishment of the battery system during the first charge cycle. After lithium removal during the first charge cycle, a large number of vacancies are generated in the crystal lattice, transforming the battery into an excellent solid electrolyte and reconstructing the continuous three-dimensional solid-state ion conduction network within the positive electrode in situ.
[0025] By adopting the above scheme, the method of the present invention has the following advantages:
[0026] 1. This invention constructs a metastable solid solution structure with heavy metal doping, enabling the material to retain active lithium after the initial extraction, relying on doped metal ions (such as Zr) 4+ Ta 5+ The strong polar MO bonds in the lithium matrix create a pillar effect, preventing lattice collapse and transforming the material in situ into a fast-ion conductor framework with a high lithium vacancy concentration, thus maintaining lattice stability. The high concentration of lithium vacancies generated during the extraction of active lithium forms open channels suitable for lithium-ion transport, transforming the residue into a room-temperature ionic conductor with a conductivity reaching 10⁻⁶. -4 ~10 -3 A solid-state ionic conductor with a capacitance of S / cm. This material serves a dual purpose of lithium replenishment and conduction, avoiding the increase of ineffective electrolyte weight in solid-state batteries and helping to reduce the solid-solid interface impedance of the positive electrode.
[0027] 2. This invention employs a transient pulsed electrothermal process combined with rapid cooling. Due to the extremely short heating and cooling times, the long-range thermal diffusion of atoms is restricted, causing the dopant elements to be "kinetically frozen" before phase separation and precipitation. This successfully prepares a metastable single-phase solid solution material with dual functions, effectively avoiding the formation of harmful impurity phases. It solves the problem that under the thermodynamic equilibrium conditions of long-term calcination in conventional tube furnaces, dissimilar atoms easily undergo phase separation, forming impurity phases with low lithium-ion conductivity.
[0028] 3. In the method of the present invention, the conductive agent and binder retained in the waste positive electrode material are directly defluorinated and carbonized in situ during the subsequent transient pulse electrothermal treatment, and directly participate in the carbothermic reduction reaction as an auxiliary reducing carbon source.
[0029] 4. The electrolyte of this invention is added to the positive electrode of an all-solid-state battery at 5-30% of the total mass of the positive electrode active material, and is used as an active solid electrolyte. This material achieves efficient lithium replenishment to the battery system during the first charge cycle. After lithium removal during the first charge cycle, a large number of vacancies are generated in the crystal lattice, transforming it into an excellent solid electrolyte, and reconstructing the continuous three-dimensional solid ion conduction network inside the positive electrode in situ.
[0030] 5. The method of this invention eliminates the need for complex strong acid leaching and multi-step wet purification processes on waste positive electrode sheets. This process can directly accommodate residual conductive carbon and difficult-to-treat organic polymer binders in the electrode sheets, utilizing their carbonization at transient high temperatures as a reducing agent to participate in the phase change reaction. This method shortens the waste battery processing flow and achieves economical, efficient, and green recycling of waste resources. Attached Figure Description
[0031] Figure 1 This is a flowchart illustrating the preparation process of the solid electrolyte with lithium replenishment function proposed in this invention.
[0032] Figure 2 The graph shows the first-cycle charging voltage curve of the product of Example 1 as an active solid electrolyte and lithium supplement additive in a lithium-ion half-cell. Detailed Implementation
[0033] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0034] Example 1: Preparation of Zr-containing lithium-supplemented solid electrolyte from waste lithium cobalt oxide, with the chemical formula: Li 5.6 Co 0.8 Zr 0.2 O4:
[0035] (1) Raw material ratio: Take waste LiCoO2 powder, LiOH powder, carbon black and ZrO2 nano powder with an average particle size of 50 nm obtained by dismantling and cleaning the waste 3C battery according to the stoichiometric ratio of the elements in the above chemical formula, and take additional carbon black according to the stoichiometric ratio of the trivalent cobalt in LiCoO2 to divalent. Place them in a mechanical ball mill and grind and mix for 30 min to obtain mixed powder.
[0036] (2) Joule rapid pulse heating: The above mixed powder is pressed into a thin sheet under a pressure of 5 MPa and placed in a quartz tube Joule thermal reactor protected by high-purity argon gas. The two ends are clamped tightly with copper electrodes. A transient pulse current is applied to the electrodes to rapidly heat the sample to 1500 ℃ within 1 second and hold it at this temperature for 20 seconds.
[0037] (3) Rapid cooling: The current pulse is cut off instantly, and the sample is rapidly cooled after losing the heat source, thus obtaining the target Zr-containing single-phase metastable solid electrolyte material.
[0038] (4) Application verification of all-solid-state battery: The single-phase metastable solid solution powder prepared above is used as an active solid electrolyte with lithium replenishment function. It is mixed with commercial LiCoO2 positive electrode active material, conventional sulfide solid electrolyte (Li6PS5Cl) and conductive carbon powder in an agate mortar at a mass ratio of 10:70:15:5 by dry grinding to obtain composite positive electrode powder. In a Teflon (PTFE) insulating mold with an inner diameter of 10 mm, an appropriate amount of high specific energy silicon-carbon composite negative electrode (Si / C) powder (silicon content 20%), Li6PS5Cl solid electrolyte powder (as a separator layer) and the above composite positive electrode powder are added in sequence. After each addition of powder, it is lightly pressed and flattened. Finally, it is cold-pressed under a pressure of 300 MPa to make it into a dense three-layer integrated solid battery electrode. After connecting the stainless steel current collector, it is assembled into an all-solid-state full battery.
[0039] Example 2: The difference from Example 1 is as follows:
[0040] The chemical formula is: Li 5.2 Co 0.6 Zr 0.4 O4.
[0041] Example 3: The difference from Example 1 is as follows:
[0042] The chemical formula is: Li 5.9 Co 0.95 Zr 0.05 O4.
[0043] Example 4: The difference from Example 1 is as follows:
[0044] The chemical formula is: Li 5.1 Co 0.7 Ta 0.3 O4;
[0045] The Joule heating parameters are set as follows: heat up to 1600 ℃ in 1 second, hold for 20 seconds, and then turn off the power to cool down quickly.
[0046] Example 5: The difference from Example 1 is as follows:
[0047] The chemical formula is: Li 5.7 Co 0.9 Nb 0.1 O4;
[0048] The Joule heating parameters are set as follows: heat up to 1600 ℃ in 1 second, hold for 20 seconds, and then turn off the power to cool down quickly.
[0049] Example 6: The difference from Example 1 is as follows:
[0050] The chemical formula is: Li 5.6 Ni0.4 Co 0.16 Mn 0.24 Zr 0.2 O4;
[0051] Waste cathode powder is replaced with recycled ternary cathode LiNi. 0.5 Co 0.2 Mn 0.3 O2 (NCM523), with ZrO2 as the metal element precursor; the molar ratio of the system is controlled as (Ni+Co+Mn):Zr=0.8:0.2.
[0052] Comparative Example 1: The difference from Example 1 is that:
[0053] When preparing the all-solid-state battery, the solid solution material with lithium replenishment function prepared in the embodiments of the present invention is not added. Instead, the proportion of conventional sulfide solid electrolyte (Li6PS5Cl) in the composite cathode is increased to 25% to ensure that the relative loading of the cathode active material (LiCoO2) is completely consistent with that in Example 1 (i.e., the cathode ratio is LiCoO2:Li6PS5Cl:conductive carbon = 70:25:5).
[0054] Comparative Example 2: The difference from Example 1 is that:
[0055] Without adding any solid electrolyte nucleating metal precursors (such as ZrO2), waste LCO is converted into conventional pure-phase Li6CoO4 lithium supplementation additives using only Joule thermal carbothermal reduction; in the full cell assembly, this pure-phase Li6CoO4 is mixed with LiCoO2, Li6PS5Cl and conductive carbon in a ratio of 10:70:15:5 to prepare a composite cathode.
[0056] Comparative Example 3: The difference from Example 1 is that:
[0057] Instead of using transient pulse Joule heating, the mixed powder is pressed into thin sheets and placed in a conventional high-temperature tube furnace. Under the protection of an argon atmosphere, the temperature is slowly increased to 800 ℃ at a constant rate of 5 ℃ / min and held for up to 12 hours. Then, the furnace is allowed to cool slowly to room temperature naturally.
[0058] Electrochemical performance testing:
[0059] 1. The solid electrolyte material obtained in step (3) of Example 1 was mixed with PVDF and conductive carbon black in a mass ratio of 8:1:1 to prepare an electrode sheet and assembled into a half cell. The first-cycle charging curve was tested as follows: Figure 2 As shown.
[0060] Figure 2This indicates that the material exhibits a significant delithiation voltage plateau during the first charge cycle, with a charge specific capacity as high as 685 mAh / g, which can effectively provide extremely abundant active lithium compensation for the battery.
[0061] 2. Prepare half-cells using the methods described above for Examples 1-6 and Comparative Examples 2-3, perform a first-cycle complete delithiation (charge to 4.5 V), then disassemble in a glove box, wash and scrape off the residual powder, and cold press to form a dense sheet; test the AC impedance (EIS) of the dense sheet at 25°C to accurately calculate the solid-state lithium-ion conductivity of the residual skeleton, and the results are shown in Table 1.
[0062] Table 1: Test results of ultimate delithiation capacity and ionic conductivity after delithiation Group Heat treatment process Doping elements and proportions First charge capacity (mAh / g) Room temperature (25°C) ionic conductivity (S / cm) of the residue after lithium removal. Example 1 Joules Zr (x=0.2) 685 <![CDATA[3.5×10 -4 ]]> Example 2 Joules Zr (x=0.4) 550 <![CDATA[5.5×10 -4 ]]> Example 3 Joules Zr (x=0.05) 720 <![CDATA[0.8 ×10 -4 ]]> Example 4 Joules Ta (x=0.3) 612 <![CDATA[4.8×10 -4 ]]> Example 5 Joules Nb (x=0.1) 675 <![CDATA[1.2×10 -4 ]]> Example 6 Joules NCM ternary + Zr 562 <![CDATA[2.8×10 -4 ]]> Comparative Example 2 Joules none 740 <![CDATA[1.5×10 -8 ]]> Comparative Example 3 slow cooking in a tubular furnace Zr (x=0.2) 515 <![CDATA[4.2×10 -7 ]]>
[0063] As shown in Table 1, after the solid electrolyte materials in Examples 1-6 are deactivated by active lithium, due to the absence of lattice collapse and the formation of a large number of lithium vacancies, they all convert to room-temperature ionic conductivity as high as 10. -4 It is a fast ion conductor on the order of S / cm and can be used as a solid electrolyte to conduct lithium; however, the conductivity of Comparative Example 2 (a conventional pure-phase Li6CoO4 lithium supplement) drops drastically to 1.5 × 10⁻⁶ after delithiation. -8 S / cm, completely reduced to a dead weight of insulation; Comparative Example 3, prepared by slow firing in a tube furnace, also exhibited extremely poor ion conduction ability due to phase separation.
[0064] 3. The first-cycle discharge capacity and long-cycle life of the lithium cobalt oxide||silicon-carbon (LiCoO2||Si / C) all-solid-state batteries assembled in each embodiment and comparative example were tested, and the results are shown in Table 2.
[0065] Table 2: Electrochemical performance test results of all-solid-state batteries in each embodiment and comparative example Group Positive electrode components negative electrode components First-cycle discharge specific capacity (mAh / g) Capacity retention rate (%) after 200 long cycles Example 1 <![CDATA[LiCoO2 + Li6PS5Cl + Example 1 + Carbon (70:15:10:5)]]> Si / C 172.4 91.2 Example 2 <![CDATA[LiCoO2 + Li6PS5Cl + Example 2 + Carbon (70:15:10:5)]]> Si / C 170.8 92.5 Example 3 <![CDATA[LiCoO2 + Li6PS5Cl + Example 3 + Carbon (70:15:10:5)]]> Si / C 172.8 86.4 Example 4 <![CDATA[LiCoO2 + Li6PS5Cl + Example 4 + Carbon (70:15:10:5)]]> Si / C 170.6 90.8 Example 5 <![CDATA[LiCoO2 + Li6PS5Cl + Example 5 + Carbon (70:15:10:5)]]> Si / C 171.2 87.5 Example 6 <![CDATA[LiCoO2 + Li6PS5Cl + Example 6 + Carbon (70:15:10:5)]]> Si / C 170.9 89.1 Comparative Example 1 <![CDATA[LiCoO2 + Li6PS5Cl + carbon (70:25:5, without lithium supplement agent)]]> Si / C 141.5 72.6 Comparative Example 2 <![CDATA[LiCoO2 + Li6PS5Cl + pure-phase Li6CoO4 + carbon (70:15:10:5)]]> Si / C 171.3 78.3 Comparative Example 3 <![CDATA[LiCoO2 + Li6PS5Cl + slow-burning product + carbon (70:15:10:5)]]> Si / C 167.8 68.1
[0066] As shown in Table 2, in Comparative Example 1, due to the lack of a lithium replenishment agent, the high-capacity silicon-carbon anode consumed a large amount of active lithium from the cathode in the first cycle, resulting in an initial discharge capacity of only 141.5 mAh / g for the entire battery. Although Comparative Example 2 added pure-phase Li6CoO4, which provided lithium replenishment (increasing the capacity to 171.3 mAh / g in the first cycle), the delithiation product of this lithium replenishment agent was non-lithiductive, severely hindering the interfacial ion transport between Li6PS5Cl and LiCoO2 inside the cathode, leading to a rapid increase in cycle polarization and a sharp drop in capacity retention to 78.3% after 200 cycles. In contrast, the all-solid-state battery doped with the materials from Examples 1-6, while receiving sufficient lithium compensation in the first cycle (with capacities all exceeding 170 mAh / g), had its residue transform into a high-conductivity solid electrolyte framework in situ, effectively reducing interfacial impedance and exhibiting extremely excellent long-cycle stability (capacity retention exceeding 85% after 200 cycles).
[0067] For those skilled in the art, various other corresponding changes and modifications can be made based on the technical solutions and concepts described above, and all such changes and modifications should fall within the protection scope of the claims of this invention.
Claims
1. A solid electrolyte with lithium replenishment function, characterized in that, The solid electrolyte is a single-phase metastable solid solution; its general chemical formula is Li. (6-a) TM (1-x) M x O (4-b) ; Wherein, TM is a transition metal element, including one or more of cobalt, nickel, manganese or iron; M is a metal dopant element, including one or more of zirconium, tantalum, niobium, titanium, tungsten, molybdenum or hafnium, and 0.05≤x≤0.4; a and b are lattice defect coefficients caused by the influence of the valence state of the doped metal, satisfying 0≤a≤1 and 0≤b≤1.
2. The solid electrolyte with lithium replenishment function according to claim 1, characterized in that, The single-phase metastable solid solution has an antifluorite structure or a cationic disordered rock salt crystal structure; the metal doping element M is uniformly dissolved in the crystal lattice by in-situ substitution of some TM sites; there are no independent M element oxides or M-containing impurity phases inside the solid electrolyte.
3. The solid electrolyte with lithium replenishment function according to claim 1, characterized in that, The room temperature solid-state electrolyte has a lithium-ion conductivity of not less than 1.0 × 10⁻⁶. -4 S / cm.
4. A method for converting waste positive electrodes into a solid electrolyte with lithium replenishment function as described in any one of claims 1 to 3, characterized in that, Includes the following steps: a. The recovered cathode powder containing transition metal, lithium source, reducing carbon source and precursor compound of metal dopant element M are mixed evenly according to the stoichiometric ratio corresponding to the chemical formula to obtain a solid-phase mixed precursor. b. In an oxygen-free environment, the solid-phase mixed precursor is subjected to a transient high-current pulse for rapid heating, which triggers transient carbothermic reduction and atomic rearrangement reaction; c. After reaching the set ultra-high transient peak temperature and holding it at that temperature for an extremely short time, the current pulse is instantly cut off, allowing the reaction system to be rapidly cooled at room temperature. This interrupts the long-range thermodynamic diffusion of atoms, forcing the M element to be kinetically trapped in a lithium-rich transition metal lattice, thus obtaining the desired result.
5. The method according to claim 4, characterized in that, The lithium source includes one or more of Li2O, LiOH, Li2CO3, Li2O2 or lithium acetate; the precursor compound of the metal dopant element M has an average particle size of 10~200 nm.
6. The method according to claim 4, characterized in that, The reducing carbon source includes one or more of the following: micronized graphite, carbon black, graphene, multi-walled carbon nanotubes, sucrose, glucose, or starch.
7. The method according to claim 4, characterized in that, The rapid heating rate is 1000~20000℃ / s; the ultra-high transient peak temperature is 1000~2800℃, and the holding time is 5~60 s.
8. The method according to claim 4, characterized in that, The cooling rate of the rapid cooling is not less than 1000 K / s.
9. The method according to claim 4, characterized in that, The cathode powder containing transition metals obtained in step a is not subjected to leaching for purification, and retains the original conductive agent and binder.
10. The application of a solid electrolyte with lithium replenishment function as described in any one of claims 1 to 3 in the preparation of an all-solid-state battery or a solid-liquid hybrid battery.