36 results about "Iron pyrophosphate" patented technology

This invention provides a high-entropy doped composite sodium iron pyrophosphate cathode material, its preparation method, and a battery. The preparation method includes: passing a mixed metal source solution, a phosphorus source mixture, an oxidant solution, and a complexing agent solution into a base liquid to perform a co-precipitation reaction to obtain a precursor material; the mixed metal source solution includes an ferrous source, a nickel source, a cobalt source, a manganese source, a chromium source, and additives, wherein the additives include sodium alginate and / or sodium carboxymethyl cellulose; the precursor material, the sodium source, and the carbon source are sequentially mixed, spray-dried, and sintered to obtain the high-entropy doped composite sodium iron pyrophosphate cathode material. The preparation method of this invention introduces multiple metal elements, additives, and complexing agents during the co-precipitation reaction, enabling multiple metal elements to be uniformly doped into the crystal structure of the material. This utilizes the synergistic effect of high-entropy multiple factors to enhance the structural stability of the material, optimize electron / ion transport dynamics, and improve cycle and high-rate performance.

The application relates to F, N co-doped low-sulfur sodium iron pyrophosphate phosphate and a preparation method and application thereof, and belongs to the technical field of sodium ion battery materials, and at least one of the problems of poor rate performance and short cycle life of an existing sodium ion battery is solved. The preparation method comprises the following steps: S1, dissolving a sulfur-free iron source, a sulfur-free sodium source and a phosphorus source in deionized water, stirring and mixing to obtain a mixed solution; S2, adding a complex carbon source and a conventional carbon source into the mixed solution, and performing heating and stirring to obtain a precursor product, wherein the complex carbon source contains F and N; S3, drying the precursor product to obtain a sodium iron pyrophosphate phosphate precursor; and S4, sintering the sodium iron pyrophosphate phosphate precursor to obtain F, N co-doped low-sulfur sodium iron pyrophosphate phosphate. The sodium iron pyrophosphate phosphate positive electrode material has a carbon coating layer, N elements are doped in the carbon coating layer, and F elements are doped in the sodium iron pyrophosphate phosphate, so that the rate performance and the cycle life of the material are improved.

This invention relates to a method for preparing sodium iron pyrophosphate material. The preparation method includes the following steps: S1, mixing waste phosphoric acid, a trivalent iron source, and an acidic compound to react and obtain an iron-based phosphate precursor slurry; S2, centrifuging the iron-based phosphate precursor slurry to obtain a supernatant and an iron phosphate precipitate; S3, washing the iron phosphate precipitate and dispersing it in water to obtain an iron phosphate slurry; preparing a sodium dihydrogen phosphate slurry from the supernatant; mixing the iron phosphate slurry, sodium dihydrogen phosphate slurry, a sodium source, and a carbon source to react and obtain the sodium iron pyrophosphate material. The preparation method provided by this invention has a simplified process flow, significantly reduced energy consumption, and significantly improved resource utilization, achieving closed-loop utilization of all components. In addition, the process controllability is improved, and the obtained sodium iron pyrophosphate material exhibits excellent performance.

The application provides a battery monomer, a preparation method thereof, a battery and a power utilization device, and belongs to the technical field of sodium batteries. The battery monomer comprises a positive electrode sheet, the positive electrode sheet comprises a positive electrode film layer, the positive electrode film layer comprises an active substance, the active substance comprises 96-99 wt% of sodium iron pyrophosphate phosphate, 0-1.9 wt% of sodium ferrous phosphate and 0.6-4 wt% of sodium iron pyrophosphate, and the mass ratio of sodium iron pyrophosphate in the active substance is greater than the mass ratio of sodium ferrous phosphate. The battery monomer of the application controls the content of the main phase and the impurity phase in the active substance in the above range, which can not only improve the compaction density of the positive electrode active material, but also is beneficial to improving the compaction density of the positive electrode sheet, and can improve the charge gram capacity and the discharge gram capacity of the positive electrode active material. When the mass ratio of sodium iron pyrophosphate in the active substance is greater than the mass ratio of sodium ferrous phosphate in the active substance, the energy density and the cycle performance of the battery monomer can be further improved.

This invention relates to a core-shell structured sodium iron phosphate pyrophosphate cathode material, its preparation method, electrode sheet, and battery, belonging to the technical field of methods or devices for directly converting chemical energy into electrical energy. The core-shell structured sodium iron phosphate pyrophosphate cathode material of this invention comprises primary particles, each primary particle including: a core, a sodium iron phosphate pyrophosphate shell layer disposed on at least a portion of the surface of the core, and a carbon coating layer located within the pores and on the surface of the sodium iron phosphate pyrophosphate shell layer; the core includes a NASICON-type sodium-ion inorganic solid electrolyte with an average particle size ≤50nm; the average thickness of the sodium iron phosphate pyrophosphate shell layer is ≤500nm; the chemical formula of the sodium iron phosphate pyrophosphate shell layer is Na₄Fe₂O₃. 3‑ x M x (PO4)2P2O7, 0≤x≤0.9, M is a doped metal element. The core-shell structured sodium iron phosphate pyrophosphate cathode material of this invention combines high solid density, high conductivity and good electrochemical performance.

The present application provides a kind of phosphorus iron compound precursor and its preparation method, sodium iron pyrophosphate phosphate, electrode sheet, battery, electric equipment, the phosphorus iron compound precursor includes the component of Fe x (PO4) y (HPO4) z ·aH2O;Wherein, 0.6

This invention relates to a Cr and Br dual-element doped polyanionic sodium-ion battery cathode material, sodium iron phosphate pyrophosphate, its preparation method, and its application, belonging to the field of sodium-ion battery technology. The general chemical formula of the cathode material of this invention is: Na₄Fe₂O₃. 3‑x Cr x (PO4)2P2O7Br y Where 0 < x < 0.5, 0 < y < 0.7; the precursor wet gel is obtained through a sol-gel process, dried, and then sintered. This invention relates to a Cr- and Br-doped polyanionic sodium-ion battery cathode material, sodium iron phosphate pyrophosphate. The Cr dopant enhances bulk stability, while the gradient distribution of Br forms a fast ion conduction layer on the surface. The two elements together improve the rate capability and cycle performance of the sodium-ion battery. This provides a modification strategy of significant reference value for cathode materials that suffer from low discharge specific capacity and poor cycle performance at high rates due to electron conductance differences.

This invention belongs to the field of sodium-ion battery cathode materials, specifically disclosing a method for preparing a sodium iron pyrophosphate / C composite material. The method involves pre-reacting iron source A and iron source B to obtain a composite iron source, then adding sodium, phosphorus, and carbon sources for mechanical mixing, followed by solvent removal to obtain precursor powder. The precursor powder is then subjected to high-temperature calcination to obtain the sodium iron pyrophosphate / C composite material. This invention also includes the material prepared by the described method and its applications. The material prepared by this method exhibits excellent fast-charging performance and long-cycle stability.

The application discloses carbon-coated doped manganese iron pyrophosphate, a preparation method and application thereof. The application controls the ratio of manganese source, iron source and phosphorus source and reaction conditions in the preparation process, so that divalent manganese and divalent iron are precipitated to form manganese iron ammonium phosphate, impurities are removed and crystallization is carried out, and finally, manganese iron pyrophosphate is obtained by calcination. The whole precipitation process does not need inert gas protection, effectively reducing the production cost; the removal of impurities and crystallization can improve the uniformity of the finished product and effectively avoid the existence of non-divalent manganese and divalent iron impurities in the finished product, improving the purity. Meanwhile, the carbon source and dopant are used for coating and doping manganese iron pyrophosphate, so that the carbon-coated doped manganese iron pyrophosphate can inhibit the elution of manganese ions when applied in lithium manganese iron phosphate, the secondary carbon coating makes the carbon layer more uniform and dense, and the performance of lithium manganese iron phosphate is significantly improved. In addition, the synthesis period of the application is short, the cost is low, and the application is suitable for large-scale popularization and application.

This invention provides a titanium-doped sodium iron pyrophosphate precursor, its preparation method, and a battery. The preparation method includes the following steps: introducing a mixed iron-titanium metal source solution, a phosphorus source solution, a pyrophosphate source solution, an oxidant solution, and a pH adjuster into a base solution to perform a co-precipitation reaction, thereby obtaining the titanium-doped sodium iron pyrophosphate precursor. The mixed iron-titanium metal source solution includes an iron source, a titanium source, a bimetallic complexing agent, and a titanium anchoring agent. The bimetallic complexing agent includes an alkanolamine compound, and the titanium anchoring agent includes an organophosphonic acid compound. The preparation method of this invention introduces titanium during the co-precipitation reaction, simultaneously adding specific metal complexing agents and titanium anchoring agents to achieve uniform bulk phase doping of titanium. This fundamentally regulates the electronic structure of the material, improves its electronic conductivity, and solves the problems of poor battery rate performance due to the poor conductivity of sodium iron pyrophosphate, as well as the problems existing in solid-state synthesis.

This invention belongs to the fields of chemical metallurgy and environmental protection technology, specifically relating to a method for recovering ferrophosphate and simultaneously removing thorium from rare earth waste residue, and a ferrophosphate product. The method targets rare earth waste residue containing insoluble ferrophosphate. After grinding pretreatment, it undergoes enhanced acid hydrolysis at 75-85°C using 70-80% sulfuric acid. The high concentration of protons disrupts pyrophosphate bonds, achieving efficient leaching of phosphorus and iron while inhibiting the dissolution of calcium impurities. The strongly acidic filtrate after solid-liquid separation is subjected to multi-stage extraction using a primary amine extractant (N1923) to selectively remove radioactive thorium. The raffinate is then pH-controlled to induce the synthesis of battery-grade ferrophosphate. This invention achieves a phosphorus recovery rate >92% and a thorium removal rate >99.5%, not only solving the environmental pollution problem caused by rare earth waste residue storage but also preparing a high-value-added lithium battery cathode material precursor.

This application relates to the field of new energy technology, and particularly to sodium iron pyrophosphate precursor and its preparation method, cathode material and its preparation method, and battery. The sodium iron pyrophosphate precursor comprises iron phosphate, iron pyrophosphate, an impurity phase, and water of crystallization. When the water of crystallization accounts for no more than 1% of the mass of the sodium iron pyrophosphate precursor, the mass percentage of pyrophosphate in the precursor is 8-30%, and the impurity phase accounts for no more than 4% of the mass of the precursor. Using a precursor with pyrophosphate content within the above range, the PO4 content in the crystal can be increased during the subsequent synthesis of sodium iron pyrophosphate. 3‑ with Fe 3+ Na + By combining the energy barrier of individual phase formation, the formation of electrochemically inactive NFP impurity phases can be suppressed, which is beneficial to improving the purity of the main phase of NFPP material and improving the specific capacity and rate performance of the battery.

The application discloses modified sodium iron pyrophosphate phosphate, a preparation method, application, slurry, an electrode piece and a battery. The preparation method of the modified sodium iron pyrophosphate phosphate comprises the following steps: performing gas phase deposition of powder on an Al2O3 nano layer oriented growth (010) crystal face to obtain the modified sodium iron pyrophosphate phosphate; and the powder is manganese and titanium doped sodium iron pyrophosphate phosphate powder containing a fluorinated layer on the surface. Through the triple synergy of Mn / Ti double site doping, crystal face selective Al2O3 coating and gas phase fluorination, the effects of improving electronic conductivity, inhibiting electrolyte interface side reactions and improving the low-temperature performance of the battery are achieved.

This invention relates to the field of sodium-ion battery technology, specifically disclosing a sodium iron pyrophosphate (NFPP) cathode material, its preparation method, and its application. The preparation method includes: using iron phosphate as the iron source, mixing it with a specific sodium source, phosphorus source, and composite carbon source; adjusting with deionized water; and then performing precision sand milling to control the slurry particle size D50 within 0.30~0.35 μm to ensure uniform elemental mixing; subsequently, spray drying is performed to obtain a precursor with high sphericity and narrow particle size distribution; finally, programmed sintering is carried out under an inert atmosphere to obtain the final product. This invention solves the problems of uneven elemental distribution, impurity phase formation, low material compaction density, and poor electrochemical performance in existing technologies through synergistic optimization of the entire process chain of sand milling-spray drying-sintering. The obtained NFPP material has a high-purity phase structure. The sodium iron pyrophosphate cathode material prepared by the method of this invention can achieve a 0.1C discharge specific capacity of 101 mA·hg. ‑1 The 1C discharge specific capacity can reach 93 mA·hg ‑1 It is suitable for the preparation of high-performance sodium-ion batteries.

The application relates to the technical field of batteries, in particular to a positive electrode material and a preparation method and application thereof. The positive electrode material comprises a substrate and a coating layer coated on at least part of the surface of the substrate; the substrate comprises sodium pyrophosphate; the coating layer comprises carbon material and sodium sulfide; the carbon material comprises a doping element; and the doping element comprises S and F. Compared with the prior art, the application improves the electronic conductivity of the sodium pyrophosphate positive electrode material by doping the double coating layer with carbon and sodium sulfide in combination with sulfur and fluorine, and further applies the sodium pyrophosphate positive electrode material in a sodium ion battery to improve the electrochemical performance.

This invention provides a composite material of sodium iron pyrophosphate and sodium vanadium phosphate, its preparation method, and its application. The preparation method includes the following steps: S1. A first mixing of a first sodium source, a vanadium source, a first phosphorus source, and a first carbon source to obtain a sodium vanadium phosphate precursor; S2. A first calcination of the precursor in S1 to obtain sodium vanadium phosphate; the first calcination includes calcination at 700-900℃; S3. A second mixing of the sodium vanadium phosphate in S2 with an iron source, a second sodium source, a second phosphorus source, and a second carbon source to obtain a sodium vanadium phosphate composite powder coated with the sodium iron pyrophosphate precursor; S4. A second calcination of the composite powder in S3 to obtain the sodium iron pyrophosphate and sodium vanadium phosphate composite material; the second calcination temperature is 500-600℃. The preparation method provided by this invention takes into account the optimal crystallization temperatures of sodium iron pyrophosphate and sodium vanadium phosphate, thereby improving the rate performance of the cathode material.

The invention discloses a ferric sodium phosphate pyrophosphate material and a preparation method thereof, a positive plate, a sodium battery and electric equipment, the ferric sodium phosphate pyrophosphate material comprises ferric sodium phosphate pyrophosphate particles, at least part of the adjacent ferric sodium phosphate pyrophosphate particles are connected through a carbon network, carbon coating layers are arranged on the surfaces of the ferric sodium pyrophosphate particles. When the ferric sodium pyrophosphate material is used as a sodium battery positive electrode material, the ferric sodium pyrophosphate material has good low-temperature performance and excellent rate capability.

This invention discloses a dual-gradient lithium manganese iron phosphate material and its preparation method. A radially dual-gradient distribution of manganese iron pyrophosphate precursor is prepared by a stepwise continuous co-precipitation method, strictly achieving the structural design of high manganese in the inner layer and low manganese in the outer layer, and low doping of Mg-Al composite in the inner layer and high doping of Mg-Al composite in the outer layer. Subsequently, the precursor is uniformly mixed with lithium source and organic carbon source, and then calcined at high temperature. The resulting dual-gradient cathode material can not only rely on the high manganese composition of the inner layer to ensure the high-voltage energy density of the material, but also precisely suppress the surface Jan Taylor effect, disproportionation reaction and manganese dissolution through the synergistic effect of low manganese and high doping in the outer layer, thus alleviating the high-voltage side reactions above 4.2V, while taking into account both bulk lithium-ion transport and structural stability.

The application provides a preparation method of a sodium iron phosphate pyrophosphate positive electrode material, a positive electrode material and an electrochemical device. The preparation method comprises the following steps: mixing a sodium source, an iron source, a phosphorus source and a first carbon source, performing one-time grinding and drying, and then performing one-time sintering to obtain a sodium iron phosphate pyrophosphate precursor; dispersing the sodium iron phosphate pyrophosphate precursor, the first carbon source and an organic acid in a solvent, performing two-time grinding, and then drying to obtain a powder, wherein the organic acid comprises at least one of glyoxylic acid, phthalic acid, maleic acid, malic acid, oxalic acid, citric acid, acetic acid, squaric acid and tartaric acid; and performing two-time sintering on the powder to obtain the sodium iron phosphate pyrophosphate positive electrode material. The sodium iron phosphate pyrophosphate positive electrode material prepared by the preparation method has the advantages of low surface residual alkali content, good air stability and excellent electrochemical performance.

The application provides a sodium iron pyrophosphatediphosphate precursor, a preparation method of the sodium iron pyrophosphatediphosphate precursor, a positive electrode active material, a preparation method of the positive electrode active material, a battery cell and an electric device. The sodium iron pyrophosphatediphosphate precursor comprises phosphate and iron elements, and the valence of the iron element is positive divalent. The sodium iron pyrophosphatediphosphate prepared by using the precursor has good first charge-discharge capacity, and meanwhile, good powder compaction density is also considered.

This invention relates to the field of sodium-ion battery materials technology, and discloses a high-entropy doped polyanionic cathode material and its preparation method. It aims to solve the problems of low intrinsic conductivity, poor capacity performance under high compaction density, and easy component segregation in traditional sodium iron pyrophosphate-based cathode materials. The method involves wet mixing of Fe source, at least three M sources, P source, and Na source in deionized water according to the product molar ratio, adjusting the pH to 0-3 to obtain a precursor solution with a total Fe and M ion concentration of 1-4 mol / L. The precursor powder is obtained by spray pyrolysis, then mixed with a carbon source and calcined under an inert atmosphere to obtain the target material. This invention achieves uniform mixing of multiple elements at the atomic scale, optimizes the electronic structure of the material, maintains excellent capacity performance under high compaction density, and significantly improves the volumetric energy density of the battery. Furthermore, the preparation process is short, controllable, and reproducible, showing excellent prospects for industrialization and commercial application.

The application discloses a kind of sodium pyrophosphate iron phosphate sodium positive electrode materials and preparation method and application, it is related to sodium ion battery positive electrode material technical field, first by electrochemical synthesis method preparation doped modified sodium ferrate, subsequently it is as precursor with phosphorus source, iron source is mixed according to specific proportion, high purity, high performance sodium pyrophosphate iron phosphate positive electrode material of phosphoric acid is prepared by two-step sintering process.The method utilizes the high reactivity of sodium ferrate and self-doping effect, realizes the uniform distribution of element at atomic level, significantly improves the purity, structural stability and electrochemical performance of final product.The obtained sodium pyrophosphate iron phosphate material shows high reversible specific capacity, excellent cycle stability and high rate performance in sodium ion battery, suitable for large-scale sodium ion battery production.

The application discloses a sodium iron pyrophosphate positive electrode material and a preparation method and application thereof. The sodium iron pyrophosphate positive electrode material is a double-carbon-layer sodium iron pyrophosphate material, which comprises sodium iron pyrophosphate particles, a first carbon layer coated on the surface of the sodium iron pyrophosphate particles, and a second carbon layer coated on the surface of the first carbon layer. The first carbon layer is in-situ coated on the surface of the sodium iron pyrophosphate particles, thereby avoiding large particle agglomeration of the sodium iron pyrophosphate during the generation process, so that the diffusion path of ions in the particle interior is shortened. The second carbon layer is coated on the surface of the first carbon layer, thereby modifying the surface and preventing the sodium iron pyrophosphate from being exposed, and effectively improving the iron ion dissolution problem. The double-carbon-layer sodium iron pyrophosphate electrode material is prepared by adopting a solid phase method and dry ball milling, the synthesis process is simple, and the electrode material can be easily produced in batches in an industrialized manner. The electrode material provided by the application can exhibit good cycle stability and capacity performance in organic electrolyte and aqueous electrolyte.

This invention discloses a method for preparing a non-stoichiometric sodium iron pyrophosphate cathode material co-doped with fluoride and manganese ions, relating to the field of sodium-ion battery cathode material preparation technology. The method is characterized by: doping non-stoichiometric sodium iron pyrophosphate with fluoride and manganese ions. The introduction of manganese ions expands the lattice volume, widening the lattice channels, while the introduction of highly electronegative fluoride ions affects the electron cloud density of surrounding atoms. Both synergistically improve the kinetic performance of the cathode material, resulting in a non-stoichiometric sodium iron pyrophosphate cathode material co-doped with fluoride and manganese ions exhibiting superior electrochemical performance. The preparation method of this invention has advantages such as simple preparation, environmental friendliness, and low cost, and has good prospects for commercial application.

This invention provides a high-pressure compacted sodium iron pyrophosphate cathode material, its preparation method, and its application. The preparation method of the high-pressure compacted sodium iron pyrophosphate cathode material includes: weighing sodium, iron, and phosphorus sources according to the stoichiometric ratio of sodium iron pyrophosphate, adding carbon source and solvent, and mixing and grinding to obtain a precursor slurry; spray drying the precursor slurry to obtain precursor powder; compacting and granulating the precursor powder under a pressure of 10 MPa to 80 MPa to obtain denser precursor particles; and finally sintering at 500℃ to 650℃ for 6 to 15 hours under an inert atmosphere. This invention effectively eliminates internal cavities and interparticle gaps in the precursor through compaction and granulation, and controls the pressure within the range of 10 MPa to 80 MPa. The subsequent sintering process improves the density of the cathode material while controlling the impurity phase content to below 1 wt% and maintaining good electrochemical performance.

The application provides a high-compaction-density sodium iron pyrophosphate positive electrode material and a preparation method thereof, and belongs to the field of sodium ion batteries. The preparation method of the high-compaction-density sodium iron pyrophosphate positive electrode material comprises the following steps: preparing amorphous FePO4xH2O, wherein 1≤x≤4; mixing the amorphous FePO4xH2O with a phosphorus source, a supplementary sodium source, a carbon source and a solvent to obtain a first slurry; performing dispersion and drying treatment on the first slurry to obtain a precursor; and performing sintering treatment on the precursor to obtain the sodium iron pyrophosphate positive electrode material. The method provided by the application can fuse primary particles into secondary particles with a high compactness, and the compaction density of the sodium iron pyrophosphate positive electrode material prepared by the method can reach 2.0-2.2 g / cm 3 , effectively solving the technical problem of low compaction density of the sodium iron pyrophosphate positive electrode material, and making the sodium ion battery prepared from the positive electrode material have a high energy density.

This invention relates to the field of lithium-ion battery anode material technology, and discloses a method for preparing an iron ammonium pyrophosphate anode material, comprising the following steps: S1: grinding ferric oxide and ammonium dihydrogen phosphate to obtain a mixed powder; S2: calcining the mixed powder obtained in S1 under an inert atmosphere, cooling, washing, and drying to obtain the iron ammonium pyrophosphate anode material, wherein the chemical formula of iron ammonium pyrophosphate is NH4FeP2O7. In S1, ferric oxide is α-Fe2O3, and the molar ratio of ferric oxide to ammonium dihydrogen phosphate is 1:6.3-7. In S2, the calcination conditions are a calcination temperature of 200°-300°C, a calcination time of 1-3 h, and a heating rate of 2°-5° / min. The anode material obtained by this invention has excellent lithium-ion diffusion rate, stable structural characteristics, excellent discharge specific capacity, good cycle stability, and good rate performance.

This invention provides a glycosylated peptide chelated iron pyrophosphate supplement, its preparation method, and its application. The raw materials for preparing the glycosylated peptide chelated iron pyrophosphate supplement include glycosylated peptides, iron pyrophosphate, and a solubilizer. The glycosylated peptide is a β-glucan-grafted casein phosphopeptide, and the solubilizer is sodium pyrophosphate. The glycosylated peptide chelated iron pyrophosphate supplement of this invention exhibits good water solubility, color stability over a wide pH range, coexistence with nutrients such as vitamin C and oils, high iron loading capacity, good stability in gastric juice, sustained iron release in simulated intestinal fluid, and high iron absorption and utilization rate, significantly improving anemia in iron-deficiency anemia mice. The excellent absorption performance and superior physicochemical properties of the glycosylated peptide chelated iron pyrophosphate supplement of this invention make it a potential candidate for widespread application in the iron supplement market.

The application discloses a positive electrode active material, a sodium-ion secondary battery and an electric device, and belongs to the technical field of batteries; by adopting a first sodium iron pyrophosphate material and a second sodium iron pyrophosphate material with different effective phase contents and different particle sizes as a positive electrode active material, and by controlling Dv50 of the whole positive electrode active material to meet a specific range, the positive electrode active material layer can simultaneously have a high effective phase content and a high compaction density, and thus the energy density of the secondary battery can be improved.

The application discloses a kind of composite positive electrode material of core-shell structure and its preparation method, the material includes with sodium iron pyrophosphate phosphate as core body core body material, it is characterized in that, the core body material is successively coated with fast ion conductor layer and conductive carbon layer outside, wherein, the fast ion conductor layer includes lithium iron phosphate.By constructing lithium iron phosphate fast ion conductor shell layer and external conductive carbon layer on the surface of sodium iron pyrophosphate phosphate core, a synergistically enhanced core-shell conductive network is formed, which improves the ion and electron conduction capacity of the material.