694 results about "Interfacial impedance" patented technology

The invention provides a high-stability lithium-rich manganese-based positive electrode material and a preparation method thereof, and relates to the technical field of lithium-rich manganese-based positive electrode materials, and the method comprises three steps of preparation of a homogeneous precursor, solid-state mechanical fusion doping and coating, and high-temperature sintering; a lithium-rich manganese-based precursor is prepared by adopting a homogeneous coprecipitation process, uniform distribution of metal ions is ensured, then an aluminum source, a zirconium source and a fluorine source are introduced as doping agents, phosphate and a titanate coating agent are combined, doping and coating integrated treatment is realized through mechanical ball milling, and the lithium-rich manganese-based composite material is obtained. And finally, mixing with a lithium source in an argon atmosphere, and carrying out high-temperature sintering of temperature programming and staged heat preservation to form a stable composite coating layer in situ. Therefore, manganese ion migration is effectively inhibited through lattice doping, a layered structure is prevented from being converted into spinel or rock salt phase, meanwhile, a nanoscale ion / electron transmission channel is constructed, interface impedance is reduced, and the charging and discharging efficiency under high voltage is improved.

The invention discloses a negative electrode interface modification material, a negative electrode plate, a positive electrode interface functional layer, a positive electrode plate, a solid-state battery and a power utilization device, and relates to the technical field of batteries, the negative electrode interface modification material comprises a first polymer matrix, a reinforcing filler, a conductive agent and a lithium salt, the modulus of the reinforcing filler is greater than 50 GPa. The tensile strength of the negative electrode interface modification material can be improved through the first polymer matrix, breakage of a negative electrode interface modification layer is reduced, interface impedance is reduced, meanwhile, the first polymer matrix can be matched with the expansion coefficient of a silicon-based material, and bulging of a negative electrode plate is reduced. The modulus of the reinforcing filler is greater than 50GPa, so that the modulus of the negative electrode interface modification layer can be improved, the expansion of the silicon-based active material is further inhibited, the conductive agent can relieve the problem that the flexible substrate interface of the copper foil and the negative electrode interface modification layer possibly causes unsmooth electron transmission, and the lithium salt can improve the ion conduction capability and reduce the interface impedance.

The invention provides a solid-state battery and a preparation method thereof, and particularly relates to the technical field of solid-state batteries. The solid-state battery is composed of a plurality of laminated units, the laminated unit comprises a positive pole piece, an all-solid-state electrolyte membrane and a negative pole piece which are sequentially stacked according to a sandwich structure; among the positive pole piece, the all-solid-state electrolyte membrane and the negative pole piece, convex structures and concave structures which are uniformly arranged are distributed on any two mutually contacted surfaces of the positive pole piece, the all-solid-state electrolyte membrane and the negative pole piece. When the components of the solid-state battery are overlapped, the convex structures and the concave structures on the surfaces of the solid-state battery can be mutually engaged to form a stable micro-embedded structure, the interface bonding strength between the positive electrode and the electrolyte and between the negative electrode and the electrolyte is greatly enhanced through physical embedding, and the problem of unstable bonding in the prior art is solved. Meanwhile, the uniform concave-convex structure ensures the controllability and consistency of the interface contact area, effectively reduces and stabilizes the interface impedance, improves the performance consistency of the pole piece, and further improves the production yield and the overall performance stability of the battery.

The invention provides a lithium ion battery and an electric device, the lithium ion battery comprises a positive electrode, a negative electrode, a diaphragm and an electrolyte, the positive electrode comprises a positive electrode active material layer, the positive electrode active material layer comprises a positive electrode active material and an oxide solid electrolyte, and the surface of the diaphragm is provided with an oxide solid electrolyte layer; the electrolyte comprises a solvent, a lithium salt, a first additive and a second additive, the first additive comprises fluoroethylene carbonate, and the second additive comprises 1, 3-propane sultone; the lithium ion battery satisfies the following conditions: 0.72 < = (H + X) / P < = 8; 0.5 < = (A + B) / (H + X) < = 8.89; 0.16 < = H / X < = 6.4; 0.5 < = A / B < = 12. According to the lithium ion battery provided by the invention, the safety and the high and low temperature performance of the positive electrode of the lithium ion battery are remarkably improved through multi-component cooperative regulation and control, further, when the lithium ion battery meets the limitation of the relational expression at the same time, the interface impedance can be reduced to the maximum extent, and the performance of the lithium ion battery can be improved through cooperation of multi-component parameters. And synchronous optimization of thermal safety, low-temperature discharge capacity and high-temperature cycle life of the battery is realized.

The invention relates to a composite diaphragm with high ionic conductivity, a composite solid electrolyte and a preparation method thereof. The composite diaphragm is composed of a lithium lanthanum-based fluorine-doped solid electrolyte LLMOF and a base membrane, the chemical general formula of the LLMOF is Li < x > La < y > M < 1 > < z > M < 2 > < w > M < 3 > O < 6 > F, wherein M1 is a tetravalent cation, M2 is a pentavalent cation, and M3 is a hexavalent cation; 1 < x + 3y < 5, 0 < x < = 2, and 1 / 3 < y < 5 / 3; 0 < = z < = 2, 0 < = w < = 2, 0 < = u < = 2, z + w + u = 2; the base membrane is a large-aperture base membrane, and the aperture r is more than or equal to 200nm and less than or equal to 1mu m; the particle size D50 of the LLMOF is 50 nm to 1 [mu] m, and the particle size D50 of the LLMOF is less than or equal to the aperture r of the base film. According to the composite diaphragm disclosed by the invention, the LLMOF solid electrolyte with an ion channel function is introduced, so that efficient conduction of ions is realized; the particle size is matched with that of a large-aperture base membrane, the membrane can be uniformly embedded into membrane holes, a continuous conduction path is constructed, and the ionic conductivity is improved; meanwhile, the composite diaphragm has excellent thermal stability and interface wettability, interface impedance is effectively reduced, and growth of lithium dendrites is inhibited.

The invention relates to a preparation method and application of an electrode, in particular to a preparation method and application of an anti-reverse current self-supporting electrode for anion exchange membrane water electrolysis hydrogen production. The self-supporting (NiCoFe) 9S8 electrode is constructed by adopting a directional solid-phase synthesis strategy to overcome the challenge of performance degradation of the electrolytic cell. The preparation method comprises the following steps: firstly, depositing a precursor solution of FeS2 and CoCl2 on a nickel felt substrate, and then carrying out annealing treatment to obtain uniformly grown (NiCoFe) 9S8; the method not only ensures uniform distribution of multiple metal components, but also constructs firm chemical bonding and efficient charge transfer between the catalyst layer and the conductive substrate through solid-phase interface reaction, and effectively avoids interface impedance caused by introduction of an additional binder. Therefore, high-current-density water electrolysis hydrogen production under intermittent fluctuation power supply is realized. In 1M KOH, the cell voltage is almost not attenuated when the electrode stably operates for 2000h at 500mAcm <-2 >.

The invention relates to the technical field of lithium battery electrolytes, in particular to a preparation method of a polyether-based solid electrolyte and application of the polyether-based solid electrolyte in electrochemical devices such as lithium metal batteries. The polyether-based solid electrolyte material comprises a porous polymer skeleton, a cyclic ether monomer, a copper-based compound, a lithium salt and a plasticizing additive. The preparation method comprises the following steps: loading a copper-based compound into a porous polymer skeleton, adding cyclic ether, lithium salt and the like to carry out in-situ ring opening polymerization, cooperatively constructing a polyether-porous polymer skeleton three-dimensional network structure, and improving the mechanical strength of the electrolyte. Wherein the copper-based compound widens the chain spacing of the porous polymer, and is convenient for the cyclic ether monomer to penetrate into the skeleton; meanwhile, the in-situ ring-opening polymerization of the cyclic ether promotes the close contact between the electrolyte and an electrode, the interface impedance is reduced, and the ionic conductivity is improved. The polyether-based solid electrolyte prepared by the invention can promote stable circulation of a lithium metal battery.

The invention discloses an in-situ autocatalytic forming gel epidermal electrode, an electrophysiological signal monitoring system and an electrophysiological signal monitoring device. The gel precursor includes a supramolecular solvent selected from a specific monomer, a metal ion catalyst, an initiator, a cross-linking agent, and a hydrogen bond acceptor and a hydrogen bond donor. The gel precursor provided by the invention can perform autocatalysis to initiate crosslinking to form a sensing medium with an interlocking structure, and meanwhile, can form a stable interface structure with the skin to ensure that the gel precursor is tightly attached to epidermal tissues, and motion artifacts caused by relative displacement in a motion process are reduced to the greatest extent. According to the invention, the electrode is formed by gelling the gel precursor on the skin surface, and the electrode has low interface impedance so as to ensure high signal fidelity, excellent mechanical stability, dynamic adhesion, stable electrochemical performance and biocompatibility, and can be reliably used for a long time. The method can be widely applied to wearable equipment, electronic skin, medical equipment and the like.

The invention discloses a composite solid electrolyte layer, a preparation method and application, the composite solid electrolyte layer comprises a porous membrane laminated on a negative pole piece, and pores in the porous membrane and gaps between the porous membrane and the negative pole piece are filled with in-situ generated polymers. Inorganic solid electrolyte is also dispersed in the porous membrane, and lithium salt is dispersed in the polymer and the porous membrane. The composite solid electrolyte layer is obtained through in-situ polymerization of a polymer in pores in the porous membrane and gaps between the porous membrane and the negative electrode plate, and a novel interface structure with the electrode-electrolyte integration characteristic is constructed. By adopting a collaborative optimization strategy of a polymer matrix and inorganic filler double-crosslinking network system and an interface stable layer, the volume effect problem of a silicon-based negative electrode, the electrolyte interface impedance problem and the battery safety problem can be solved at the same time, so that the cycling stability and the rate capability of the lithium ion battery are remarkably improved.

The invention relates to the technical field of lithium ion batteries, in particular to a preparation method of an interface-modified high-rate lithium iron phosphate positive electrode material, which is used for solving the problems of low interface impedance, low rate capability and low energy density of the existing lithium iron phosphate. According to the preparation method, zirconium-niobium co-doped iron phosphate is used as a precursor of the lithium iron phosphate positive electrode material, a lithium ion diffusion channel is widened, the lithium ion diffusion coefficient is improved, meanwhile, an olivine structure framework is provided, a wider tunnel space is provided for lithium ion migration, zirconium-niobium provides additional electrons, and the electron conductivity is improved through cooperation of the zirconium-niobium co-doped iron phosphate and the olivine structure framework; li2ZrCl6-LiCl interface modification can isolate sulfide electrolyte from being in direct contact with a positive electrode material, and interface side reaction is inhibited; carbon nanotube coating can enhance the conductivity, reduce erosion, improve the diffusion coefficient of Li < + > and the stability of the material structure, and improve the charge-discharge rate.

The embodiment of the present application provides a positive electrode material, a secondary battery and an electric device, wherein the positive electrode material comprises a core and a coating layer arranged on the surface of the core, the core comprises a sodium ion layered oxide, and the coating layer comprises a spinel lithium salt. In the embodiment of the present application, the layered positive electrode material is tightly coated by the spinel lithium salt, so that the problem that the interface impedance of the positive electrode material of the existing sodium ion battery is large and the positive electrode adhesive is easily attacked is solved.

The invention relates to the technical field of lithium ion batteries, in particular to a halogenated electrolyte modified low-impedance positive electrode and a preparation process and application thereof. The problem that an existing lithium ion battery positive electrode material is high in impedance is solved. According to the preparation method, the carbon-coated aluminum foil is used as the positive current collector, so that the positive current collector has relatively low contact resistance and relatively high adhesion, the charge transfer resistance and the internal resistance of the battery are reduced, and the rate capability and the cycle performance of the battery are improved; a positive active material is added, C6H12O6.H2O is adopted for carbon coating to improve the electron transmission capacity of lithium iron phosphate, titanium-vanadium co-doping synergistically improves the electron conductivity, and the electron conduction impedance is reduced; the halide solid electrolyte coats lithium iron phosphate to inhibit side reaction and reduce interface impedance; carbon nano tube coating inhibits particle aggregation and reduces charge transfer impedance; and the modified conductive agent and the modified binder are added, so that the lithium ion battery has higher cycling stability, electrochemical activity and lower impedance.

The invention discloses a preparation method of a solid-state electrolyte based on chemical bonding of a silane coupling agent and a sulfide solid-state electrolyte and a preparation method of a solid-state lithium battery. A halogen ion competitive adsorption effect of a first electrolyte is cooperated with a compact siloxane network formed by the silane coupling agent; the sulfide solid electrolyte is effectively inhibited from reacting with moisture in air, electrochemical performance attenuation is delayed, the first electrolyte reacts with lithium metal to generate a stable SEI layer to inhibit dendritic crystal growth, and a wide electrochemical stable window of the second electrolyte can reduce oxygenolysis reaction with a high-voltage positive electrode, so that the electrochemical performance is improved. Chemical bonding is formed between amino groups of the silane coupling agent and lithium metal, interface contact is optimized, meanwhile, the interface ion transfer efficiency is improved through the high ionic conductivity of the second electrolyte, and the interface impedance is reduced; the defects of poor ionic conductivity and poor service life caused by poor air stability and electrochemical stability of the electrolyte in the prior art are overcome.

The invention discloses a preparation method of a polymer-sulfide solid electrolyte based on multi-scale interface design and application of the polymer-sulfide solid electrolyte in an all-solid-state lithium battery, sulfide electrolyte particles with three complementary functions of Li10SiP2S12, Li7P2S8I and Li3PS4 are utilized, and a compact and ion transmission path optimized structure is formed in a polymer matrix through a gradient distribution technology; the micron-sized particles construct a high-speed ion conduction trunk, the nano and submicron particles are tightly filled to greatly reduce the interface impedance, meanwhile, the introduction of Li7P2S8I widens an electrochemical window from the source of the material, the self-repairing functional component on the outermost layer endows the interface with dynamic intelligent response capability, and when the interface generates microcracks, the self-repairing functional component on the outermost layer can repair the surface of the material. Dynamic bonds contained in the material can be reversibly broken and reconstructed, self-repairing of damage is achieved, the endurance capacity of an interface to mechanical and chemical strain caused by temperature change and long-term circulation is enhanced, and finally high ionic conductance, excellent interface stability and wide temperature range adaptive capacity are successfully and cooperatively achieved.

The invention discloses a sulfide-oxide composite solid electrolyte based on Lewis acid-base reaction, a preparation method of the sulfide-oxide composite solid electrolyte and a battery, and relates to the technical field of solid-state batteries. Comprising a sulfide electrolyte and a composite coating coated on the surface of the sulfide electrolyte, and the composite coating comprises an oxide electrolyte and a Lewis alkaline substance. The oxide electrolyte and the Lewis alkaline substance are adopted as the composite coating material, so that the sulfide electrolyte can be isolated from air, the air stability of the sulfide electrolyte is effectively improved, and the phenomenon that the sulfide electrolyte is subjected to oxidation-reduction decomposition in the charge-discharge process is reduced; and by-products generated in the use process of the sulfide electrolyte can be neutralized in situ by the Lewis alkaline substance, so that the great increase of interface impedance is reduced, the cycle performance and high-current stability of the battery are remarkably improved, and the problem that the interface impedance is increased in the charge-discharge process of the traditional sulfide solid electrolyte is solved.

The present invention relates to a composite separator for a lithium metal battery, a preparation method for a composite separator, and a lithium metal battery. The composite separator for a lithium metal battery comprises a separator layer and an NF@MOF membrane layer, wherein the NF@MOF membrane layer is an NF membrane on which an MOF material is grown in situ. In the present invention, the separator layer is combined with the NF@MOF membrane layer, and the in-situ grown MOF material provides high ionic conductivity and low interfacial impedance, such that the prepared composite separator integrates high mechanical strength, high flexibility, high electrolyte wettability, a high liquid retention rate and excellent ionic conductivity; and the synergistic effect exerted by the components of the composite separator can promote the uniform deposition and stripping of lithium metal, suppress the growth of lithium dendrites, and prevent separator penetration that may lead to a short circuit or even fire and explosion accidents, thereby prolonging the cycle life of the lithium metal battery and improving the safety performance thereof. Thus, the composite separator of the present invention has broad application prospects in terms of lithium metal batteries.

The invention provides a positive pole piece, a solid-state battery and a preparation method of the positive pole piece, and belongs to the technical field of secondary batteries, and the positive pole piece comprises a positive current collector and a positive active material layer. Wherein the positive electrode active material layer is arranged on the positive electrode current collector, the interface layer is arranged on the positive electrode active material layer, the interface layer comprises a first polymer, and the first polymer comprises polyether sulfonate. According to the positive pole piece provided by the invention, the polymer interface layer formed by cross-linking polyether sulfonate is arranged on the surface of the positive active material layer, so that the interface contact and ion transmission efficiency between the positive pole piece and the solid electrolyte membrane are effectively improved based on good ionic conductivity, chemical stability and mechanical flexibility of the interface layer; the interface impedance between the positive pole piece and the solid electrolyte membrane is reduced, and the side reaction of a contact interface is inhibited, so that the rate capability and the cycle life of the solid-state battery are effectively improved.

The invention relates to the field of lithium ion batteries, and discloses a lithium titanate composite material and a preparation method thereof, a negative pole piece and a preparation method thereof, a lithium battery and a battery pack. The surfaces of lithium titanate particles are sequentially coated with the nitrogen-doped carbon intermediate layer and the two-dimensional MXene material outer layer, and the MXene material outer layer is formed by bridging adjacent particles through hydrogen bonds, so that a'core-shell-bridge 'three-dimensional conductive network structure is constructed, the electronic conductivity of the lithium titanate composite material is remarkably improved, the electron / ion transmission efficiency of the lithium titanate negative electrode is improved, and the lithium titanate negative electrode has a good application prospect. The lithium ion battery has excellent rate capability and cycle performance; and through collaborative optimization of the three-dimensional composite material and the electrolyte, the interface impedance is reduced, and polarization is inhibited, so that the lithium battery still keeps high capacity and long cycle stability under ultrahigh rate, and meanwhile, the problems of discontinuous conductive network and high interface impedance in the prior art are solved. And excellent rate capability and cycle performance can be achieved under ultrahigh rate.

The invention provides a gel electrolyte with a controllable polymerization degree, a preparation method of the gel electrolyte, a semi-solid lithium ion secondary battery and a preparation method of the semi-solid lithium ion secondary battery, and relates to the technical field of lithium ion batteries. Raw materials for preparing the gel electrolyte comprise a cyclic ether monomer, an initiator and a polymerization inhibitor; the cyclic ether monomer is subjected to ring opening polymerization to obtain an ether polymer; the polymerization inhibitor is an inorganic lithium salt, and the polymerization degree of the gel electrolyte is determined by the dosage of the polymerization inhibitor and the dosage of the initiator. The gel electrolyte provided by the invention has the fluidity advantage of a liquid electrolyte and the flexibility advantage of a solid polymer electrolyte, and is beneficial to maintaining a stable contact interface between the electrolyte and an electrode, reducing interface impedance and improving ion transmission.

The invention discloses a high-voltage lithium ion battery capacity compensation type electrolyte with a slow release effect, and relates to the technical field of electrolyte preparation. The electrolyte comprises a lithium salt, an organic solvent, a cosolvent and a lithium supplement agent, the cosolvent is a compound containing a nitrogen-containing heteroaromatic ring, and the nitrogen-containing heteroaromatic ring is modified with a boron group and / or a strong electron withdrawing group. According to the cosolvent, the solubility of the lithium supplement agent in an electrolyte solvent can be remarkably improved, meanwhile, the cosolvent and the lithium supplement agent can jointly participate in CEI forming an organic-inorganic hybrid component, and higher Young modulus, ion diffusion rate and interface stability are achieved, so that the interface side reaction between the electrolyte and an electrode can be effectively inhibited, and the service life of the electrolyte is prolonged. And the interface impedance is reduced, so that the capacity attenuation caused by the fracture of the electrode material structure is slowed down, and the cycling stability of the battery under high voltage is comprehensively improved. According to the invention, the problems of poor capacity compensation performance and poor interface stability under high voltage of the existing electrolyte are solved.

The invention discloses a solid electrolyte membrane for constructing a grain boundary bridge based on an APTES coupling agent and a preparation method of the solid electrolyte membrane, and belongs to the technical field of lithium batteries. According to the composite film, a gallium-doped lithium ion conductor is used as an inorganic phase, a polymer is used as an organic phase, APTES is added for ball milling, an APTES siloxane group is hydrolyzed to generate silanol, the silanol and hydroxyl on the surface of inorganic filler LGLZO are subjected to condensation, terminal amino and the polymer form a hydrogen bond, and a grain boundary bridge is successfully constructed. By adding the APTES coupling agent, the organic-inorganic interface compatibility can be enhanced, the growth of lithium dendrites can be inhibited, the interface impedance can be reduced, the interface stability and the lithium ion transmission efficiency can be improved, and the structural integrity and the electrochemical performance of the battery in the cycle process can be guaranteed; and important theoretical guidance and experimental basis are provided for structural design and performance optimization of the composite solid electrolyte membrane.

The invention relates to the technical field of solid-state batteries, and particularly discloses an all-solid-state sulfide negative-electrode-free lithium metal battery and an assembling method thereof. The battery adopts a combination of an electrolyte membrane and electrolyte powder as an electrolyte layer, the electrolyte membrane is close to a positive electrode side, and the electrolyte powder is close to a negative electrode side. According to the structure, the compaction density and density of the electrolyte layer are remarkably improved, the growth of lithium dendrites is effectively inhibited, the interface impedance is reduced, and the volume change of the positive electrode is buffered. The assembly method comprises the following steps: compounding the positive electrode and the current collector, sequentially placing the electrolyte membrane, the electrolyte powder and the negative electrode plate, and carrying out pressure-maintaining molding under a specific pressure. Experiments show that the battery has high initial specific discharge capacity, long cycle life and high capacity retention rate, and is suitable for large-scale solid-state battery manufacturing.

The invention belongs to the technical field of development and manufacturing of solid-state electrolyte materials and solid-state lithium batteries, and particularly relates to an all-solid-state oxide-polymer electrolyte membrane as well as a preparation method and application thereof. The electrolyte membrane comprises a polymer matrix, a lithium salt, butanedinitrile, lithium lanthanum zirconium tantalum oxide and graphite phase carbon nitride, the polymer matrix, the lithium salt, the butanedinitrile, the lithium lanthanum zirconium tantalum oxide and the graphite phase carbon nitride are uniformly mixed to form a solid film; the polymer matrix is polyacrylonitrile and forms a framework of the electrolyte membrane; the lithium salt, the butanedinitrile, the lithium lanthanum zirconium tantalum oxide and the graphite phase carbon nitride are at least physically and uniformly dispersed in the polymer matrix. The electrolyte membrane can be prepared through the steps of slurry preparation, defoaming treatment, membrane forming processing, drying and curing and the like, and can be used in a solid-state lithium battery, so that the contact between the electrolyte membrane and an electrode interface is improved, side reaction is inhibited, the ion transmission efficiency and mechanical property are improved, the interface impedance is reduced, and the cycling stability and safety of the solid-state lithium battery are enhanced.

The invention discloses a solid electrolyte membrane, a preparation method and a lithium battery. The solid electrolyte membrane comprises a polymer electrolyte, the structure of the polymer electrolyte is a hyperbranched polymer, a molecular chain of the polymer electrolyte contains a polyoxyethylene chain segment, ether oxygen atoms in an amorphous phase region can form coordination with lithium ions, migration of the lithium ions is facilitated, and the ionic conductivity of the solid electrolyte membrane is improved; besides, a nitrogen and sulfur element annular structure is introduced into the hyperbranched polymer, so that the mechanical strength of the solid electrolyte membrane can be effectively improved, the ionic conductivity of the solid electrolyte membrane can be further improved, the interface impedance can be reduced, and the comprehensive performance of the battery on safety performance and electrical performance is improved.

The invention discloses a sulfur-containing all-solid-state polymer electrolyte membrane, a preparation method and a lithium metal battery, and belongs to the technical field of polymer electrolytes.The method comprises the steps that 1, 4-phenylene-diacrylate and dimethyl tetrasulfide are evenly mixed and cooled to the room temperature after a reverse vulcanization reaction, and a polymer solid is obtained; the preparation method comprises the following steps: dissolving a polymer solid in dimethyl sulfoxide, adding bis (trifluoromethanesulfonyl) lithium imide, uniformly stirring and mixing, casting in a PTFE (Polytetrafluoroethylene) mold, uniformly spreading, and carrying out vacuum drying to obtain the sulfur-containing all-solid-state polymer electrolyte membrane. The ion transmission function of a liquid electrolyte is replaced by the solid ion conduction property, and the physical isolation function of a diaphragm is replaced by a compact and firm physical structure, so that the Li < + > diffusion energy barrier is reduced, the electrochemical window is widened, the interface impedance is reduced, and the interface compatibility between the positive and negative electrode materials and the solid electrolyte is improved; the lithium metal battery assembled by the electrolyte has excellent electrochemical performance and cycle performance.

The invention discloses a method for removing residual alkali on the surface of a high-nickel positive electrode material in a ternary lithium battery and application of the method, and belongs to the technical field of lithium ion battery positive electrode materials. After the lithium ion ternary positive electrode material is subjected to coating treatment, residual alkali compounds on the surface of the lithium ion ternary positive electrode material are remarkably reduced, and a coating material protection layer can be constructed on the surface of the lithium ion ternary positive electrode material in situ; therefore, an electrode / electrolyte interface structure is strengthened, side reaction and interface impedance are inhibited, and the specific discharge capacity and rate capability of the battery are remarkably improved. The method is simple and convenient in process and mild in condition, and has a good industrial application prospect.

The invention belongs to the technical field of lithium ion batteries, and particularly discloses a composite coated high-voltage lithium cobalt oxide positive electrode material as well as a preparation method and application thereof. The positive electrode material comprises an inner core, and a first coating layer and a second coating layer which sequentially coat the inner core from inside to outside; the inner core is a doped lithium cobalt oxide matrix, the chemical formula is Li1 + xCo1-yM1yM2zO2, x is more than or equal to 0 and less than or equal to 0.1, y is more than or equal to 0.001 and less than or equal to 0.05, z is more than or equal to 0.001 and less than or equal to 0.05, M1 is selected from at least one of Al, Ni and Fe, and M2 is selected from at least one of Mg, Al, Zr, Zn, Ni, Fe, Sr, Mo, Ta and W; the chemical formula of the first coating layer is La1-mNmCoO3-n.Co3O4, m is greater than 0 and less than 1, n is greater than 0 and less than 3, and N is selected from one or two of Ca, Mg, Fe, Zn, Ba and Zr; and the second coating layer is cobalt oxide of YOF and Y. The core problems of bulk phase structure degradation, serious interface side reaction, interface impedance increase and the like under high voltage can be cooperatively solved.

The invention discloses a capacity compensation type electrolyte for a high-voltage lithium ion battery as well as a preparation method and application of the capacity compensation type electrolyte, and relates to the technical field of electrolyte preparation. The electrolyte comprises a lithium salt, an organic solvent, a first additive and a second additive, the first additive can remarkably improve the solubility of the second additive in an electrolyte solvent, so that the compensation effect of the second additive on the capacity is enhanced; meanwhile, the additive disclosed by the invention can form a compact and stable positive electrode electrolyte interface film (CEI), so that the continuous decomposition of the electrolyte and the generation of byproducts are effectively inhibited, the interface impedance is reduced, and the capacity attenuation is slowed down. The problem that an existing electrolyte is poor in capacity compensation performance is solved.

The invention discloses a preparation method of a liquid metal composite silicon-based negative electrode material and application of the liquid metal composite silicon-based negative electrode material in an all-solid-state battery, and relates to the technical field of all-solid-state batteries, and the preparation method specifically comprises the following steps: S1, obtaining a silicon-based composite material compounded by a silicon-based phase and a metal phase by adopting a suspension smelting and rapid quenching technology; s2, mixing a silicon material or a silicon-based composite material with a conductive agent, and obtaining a silicon material-conductive agent powder material or a silicon-based composite material-conductive agent powder material through a sanding technology; and S3, pouring the silicon powder and liquid metal into a dispersing agent, uniformly mixing by adopting a stirring-ultrasonic-stirring method, and drying in a vacuum drying oven to obtain the silicon-based negative electrode material. According to the method, the liquid metal dynamically repairs silicon cracks by utilizing the fluidity in the charging and discharging process, and the connectivity of an internal conductive network is maintained; and by filling an electrode-electrolyte interface gap, the stability of an ion transmission channel is ensured, and the interface impedance is reduced.

The invention provides a lithium manganese iron phosphate positive electrode material, a preparation method thereof and a lithium ion battery. The lithium manganese iron phosphate positive electrode material comprises an inner core, and a first shell and a second shell which sequentially coat the surface of the inner core, wherein the inner core comprises a boron-doped lithium manganese iron phosphate material, the first shell is a boron-doped aluminum oxide layer, and the second shell is a lithium niobium tantalate layer; the doping amount of boron in the lithium manganese iron phosphate positive electrode material is gradually reduced from the inner core to the second shell layer. According to the invention, a plurality of shell layers are constructed for collaborative protection, and gradient boron doping is carried out on the inner core and the first shell, so that the intrinsic electron / ionic conductivity of lithium manganese iron phosphate is improved, the interface stress caused by element distribution mutation between different material layers is avoided, and the balance of bulk phase high conductivity-interface low impedance is realized; and the comprehensive electrochemical performance is improved.