17results about How to "Alleviate volume changes" patented technology

The application provides a high-nickel ternary material modification method and a high-nickel positive electrode material with a nitrogen-oxygen coating layer, and relates to the field of lithium ion batteries. In the high-nickel ternary material, surface lattice oxygen is gradually replaced by nitrogen atoms in a high-temperature long-time calcination process in a nitrogen-oxygen mixed atmosphere, so that a nitrogen-oxygen layer is formed on the surface, which is beneficial to the delocalization of electrons, thereby endowing the material with excellent electronic conductivity; meanwhile, the presence of the nitrogen-oxygen layer inhibits the transformation of the surface layer structure into a rock salt phase structure, which is beneficial to realizing efficient ion transport. The formation of the nitrogen-oxygen layer on the surface of the high-nickel ternary material can simultaneously improve the electronic and ionic conduction of the surface of the high-nickel positive electrode material, inhibit the interface side reaction, relieve the volume change, and thereby improve the cycle stability of the battery.

The present application relates to the technical field of sodium battery materials, in particular to a sodium supplement coating based on a spiral iron-carbon composite material and a preparation method thereof, a spiral polypyrrole template is synthesized by a chiral template method, Fe3C@CNS spiral carbon composite material rich in Fe3C nanocrystals and iron single-atom sites is prepared through iron loading, sulfidation and high-temperature pyrolysis, Na2C2O4@Fe3C@CNS composite material is prepared by highly dispersing sodium oxalate on the surface and in the pores of the spiral carbon composite material through a recrystallization method, finally, a slurry is prepared by mixing the Na2C2O4@Fe3C@CNS composite material with a conductive agent and a binder, and the slurry is coated on the surface of an electrode to form a functional sodium supplement coating. The sodium supplement coating based on the spiral iron-carbon composite material and the preparation method thereof solve the problems of poor interface stability and first-cycle irreversible sodium loss of existing sodium ion batteries, realize efficient sodium pre-activation and interface synergistic regulation, and improve the comprehensive performance of the battery.

The invention relates to the technical field of lithium ion batteries, and discloses a nickel-rich ternary positive electrode material as well as a preparation method and application thereof. The preparation method of the nickel-rich ternary positive electrode material provided by the invention comprises the following steps: S1, mixing a ternary positive electrode material precursor with a lithium salt, and sintering for the first time to obtain an intermediate product; s2, mixing the intermediate product, aluminum salt, pyrophosphoric acid and ethanol to obtain a mixed solution; and S3, drying the mixed solution, sintering for the second time, and cooling to obtain the nickel-rich ternary positive electrode material. According to the preparation method provided by the invention, the ion transport layer with high ionic conductivity is constructed on the surface of the positive electrode in situ, so that the migration kinetics of Li < + > is improved, adverse side reactions at an electrode / electrolyte interface are inhibited, and the capacity and cycle performance of the nickel-rich ternary positive electrode material under high magnification are improved.

The invention discloses a silicon negative electrode active material which sequentially comprises a silicon-based material inner core, a flexible solid electrolyte or gel electrolyte middle layer and a carbon-coated outer layer from inside to outside, the flexible solid electrolyte or gel electrolyte middle layer comprises a conductive agent, and the conductive agent comprises a carbon nanotube. According to the silicon negative electrode active material, the surface of the silicon-based material is coated with the flexible solid-state or gel-state electrolyte, so that the volume change of the negative electrode active material in the charging and discharging process is effectively relieved, the electrolyte is isolated, the stability of the negative electrode active material is improved, and the negative electrode active material has relatively high reversible specific capacity and relatively high specific surface area; and excellent long cycle performance is shown.

This invention provides a bipolar electrode and a bipolar all-solid-state battery. The bipolar electrode comprises a positive electrode film, a current collector, a bulk material layer, and a carbon material layer. Through the design of the carbonaceous framework and nucleating agent in the bulk material layer, efficient and dense lithium metal deposition is achieved under high voltage conditions. The carbon material layer significantly improves the interfacial contact between the bulk material layer and the all-solid-state electrolyte, reduces interfacial resistance, and improves the deposition and extraction efficiency of lithium metal in the bulk material layer. Furthermore, the carbon material layer provides storage space for lithium metal deposited from the positive electrode, mitigating volume changes during lithium metal deposition in the bulk material layer and improving the stability of the bipolar electrode. The bipolar all-solid-state battery fabricated using the bipolar electrode exhibits high rate capability and long lifespan.

This application provides a dynamic ion transport binder and its preparation method, a silicon-based anode, and an all-solid-state lithium-ion battery, relating to the field of solid-state batteries. The raw materials of the dynamic ion transport binder, by mass (100%), include: 60-80% nitrile compounds, 10-30% ether-based ion compounds, and 5-10% borate compounds. The dynamic ion transport binder employs a low-polarity elastic main structure, avoiding the introduction of a large number of highly active groups such as carboxyl and hydroxyl groups, thus effectively inhibiting the decomposition of sulfide electrolytes. The borate ester dynamic bonds formed by the borate compounds undergo reversible breakage and reconstruction under stress, thereby mitigating volume changes during silicon anode cycling. This dynamic ion transport binder can effectively improve the structural integrity of the silicon-based anode after cycling, reducing interfacial delamination and crack formation.

This invention discloses a method for preparing one-dimensional network nanotube MOF-derived selenide@porous carbon materials and their applications. The method includes the following steps: dispersing ZnCo-BTC nanowires in an ethanol-water solution to form a uniform suspension A; dissolving 2-methylimidazole in an ethanol-water solution to form a solution B; preheating solution B to the reaction temperature in a water bath, pouring in suspension A, stirring at a constant temperature, centrifuging the product, washing it multiple times with ethanol and water, and finally drying it to obtain a one-dimensional tubular MOF material. Annealing this one-dimensional tubular MOF material with melamine in an argon atmosphere yields a porous carbon nanotube material with a network structure. Mixing the one-dimensional network porous carbon nanotube material with selenium powder and annealing it under argon protection yields the one-dimensional network nanotube MOF-derived selenide@porous carbon material. This invention is simple to operate, the process is controllable, and the prepared product can be widely used in electrochemical energy storage, separation, catalysis, and drug sustained release.

This invention relates to the field of batteries and discloses a method for preparing nickel disulfide / copper sulfide / carbon composite hollow spheres and their applications. The invention uses hollow spherical Ni-MOF as a precursor, combined with subsequent ion exchange, PDA coating, glucose coating, carbonization, and sulfidation to prepare nickel disulfide / copper sulfide / carbon composite hollow spheres. This material inherits the porous hollow structure of Ni-MOF, providing a high-speed and efficient transport channel for ion diffusion in electrode materials, while mitigating volume change effects and improving the cycle life of sodium-ion batteries. Furthermore, the controllable introduction of appropriate amounts of copper ions through ion exchange to form a nickel-copper bimetallic sulfide heterostructure can accelerate ion diffusion kinetics, reduce the ion diffusion barrier, and enhance structural stability. Finally, the nitrogen-doped carbon derived from polydopamine carbonization in the middle layer improves the conductivity of the composite material and increases sodium storage active sites, while the outermost carbon layer derived from glucose carbonization further enhances the structural stability of the composite material.

The application discloses a kind of supercapacitor negative high-efficiency composite electrode and preparation method thereof, including the block body iron of substrate and the outer layer PrNi x Fe 1‑x O3 conductive active layer, and Fe2O3 active layer between the two, by wet chemical etching and transient high temperature joule heat method in-situ synthesis active layer, and further utilize wet chemical brush coating and transient high temperature joule heat method in-situ synthesis conductive active layer, two are asymmetric sandwich structure, it is favorable to build charge transport path, improve charge transport efficiency, at the same time, can effectively relieve the volume change generated in the process of charge and discharge of iron oxide, unlike the characteristics of particle composite structure easy to collapse, inhibit the occurrence of electrode material pulverization, wherein, using transient high temperature joule heat preparation technology, layered in-situ build heterostructure, not only simple and fast, also make the structure compact and dense, maintain the stability of overall electrode structure, improve the long-period cycle charge and discharge capacity of electrode.

The application relates to the field of sodium ion batteries, and discloses a preparation method of hierarchical porous Fe7S8 / nitrogen-doped carbon composite nanowires and application thereof. The application takes NTA as a metal ion chelating agent, chelates zinc ions and iron ions through a solvothermal reaction, and prepares a ZnFe-NTA precursor; the precursor is pyrolyzed at high temperature under an inert atmosphere, metal ion reduction is induced through a carbon thermal reaction, low-boiling-point zinc particles are volatilized, nitrogen-doped carbon formed through in-situ conversion of an organic ligand is combined, and a hierarchical porous structure is generated; finally, a gas-phase sulfuration method is adopted to form Fe7S8, and the hierarchical porous Fe7S8 / nitrogen-doped carbon composite nanowires are obtained. When the composite nanowires are used as a negative electrode of a sodium ion battery, the hierarchical porous structure can effectively promote full infiltration of electrolyte and rapid migration of sodium ions, and can improve cycle stability and rate performance.

The invention discloses a high-nickel ternary positive electrode material and a preparation method and application thereof, and belongs to the technical field of batteries and battery materials, a coating layer is formed on the surface of the high-nickel ternary positive electrode material through silicon dioxide, direct contact between an electrode material and an electrolyte is effectively isolated, and then through a thiol-ene click reaction, the high-nickel ternary positive electrode material is obtained. The graphene / titanium dioxide core-shell whisker is used as a reinforcing phase to coat the surface of the silicon dioxide coating layer again, so that the interface bonding force between the two coating layers is increased, the volume change caused by lithium ion intercalation and deintercalation can be coped, the structural stability of the material is kept, and the specific discharge capacity, the capacity retention rate and the cycling stability are favorably improved; according to the graphene / titanium dioxide core-shell whisker, titanium dioxide containing whiskers is synthesized on the surface of graphene containing a lamellar structure through microwave heating and serves as a core layer, then a shell-structure lanthanum metal framework is synthesized in a hydro-thermal mode, and the interface bonding force can be further improved through the mechanical interlocking effect.

The invention relates to the field of sodium ion batteries, and discloses a preparation method and application of a ferrocobalt bimetallic sulfide nitrogen-doped porous carbon framework composite material. The preparation method comprises the following steps: by taking aminotriacetic acid as a ligand, chelating cobalt and iron ions through ball milling to prepare a CoFe-NTA precursor; the precursor is pyrolyzed, metal ions are subjected to carbon thermal reduction, and nitrogen-doped carbon formed by in-situ conversion of nitrilotriacetic acid can be tightly combined with ferrocobalt sulfide, so that the volume change generated during deintercalation of sodium ions can be effectively relieved, the cycling stability of the material can be enhanced, and the conductivity and the sodium ion diffusion rate of the composite material can be improved; and carrying out gas-phase vulcanization to finally obtain the ferrocobalt bimetallic sulfide nitrogen-doped porous carbon framework composite material. The nitrogen-doped porous carbon framework is beneficial to contact between electrolyte and an electrode material, active sites are fully utilized, the structural stability of the composite material can be enhanced, and when the nitrogen-doped porous carbon framework is used as a sodium-ion battery negative electrode, the nitrogen-doped porous carbon framework shows excellent sodium storage performance.

This invention discloses a two-dimensional porous silicon, its preparation method, and its application in lithium batteries, belonging to the field of materials technology. The silicon-calcium alloy powder is immersed in hydrochloric acid solution, and after the reaction is complete, it is filtered and dried to obtain siloxane powder. The siloxane powder is then heat-treated in a vacuum environment, during which the siloxane is first oxidized to SiO. x SiO x Further high-temperature processing leads to a disproportionation reaction, generating uniformly distributed two-dimensional Si / SiO2. The two-dimensional Si / SiO2 is then immersed in a hydrofluoric acid solution, where the hydrofluoric acid reacts with the SiO2. After complete reaction, the mixture is repeatedly centrifuged and washed, then vacuum dried to obtain a two-dimensional silicon material with a porous structure. The preparation method of this invention is simple, controllable, and highly practical. The two-dimensional porous silicon prepared by this method possesses a crystalline structure and an ultrathin layered structure, which can effectively mitigate volume changes in the negative electrode material and accelerate lithium-ion diffusion when used in lithium-ion batteries.

This invention discloses a lignin-derived carbon-coated NiS / TiO 2 Composite materials, their preparation methods, and applications. This invention uses sodium lignosulfonate as a carbon precursor and introduces TiO2, a substance with strong adsorption properties for sodium polysulfide. 2 NiS / TiO₂ with high specific capacity and good cycle stability was prepared by hydrothermal and calcination treatment. 2 / C composite material has a simple preparation process and low cost. As a high-energy-density and high-stability sodium-ion battery anode material, it is of great significance to the development of sodium-ion battery anode materials.

The invention provides a current collector with a three-dimensional porous structure on the surface, a preparation method and a battery. The preparation method comprises the following steps: firstly, obtaining a tin / copper foil with a three-dimensional structure on the surface through constant-current electrodeposition tin; then coating an indium tin seed layer on the tin surface of the three-dimensional structure through co-electrodeposition of indium tin, and on the basis, continuously performing constant-current electrodeposition of indium to obtain indium / indium tin / tin / copper foil with a three-dimensional porous structure on the surface; and finally, enabling the indium / indium tin / tin / copper foil to form an alloy by adopting a heat treatment technology so as to obtain the current collector with a walnut-shaped three-dimensional porous structure on the surface. Therefore, the lithium nucleation overpotential can be reduced, and the uniform deposition of lithium is guided, so that the growth of lithium dendrites and the volume expansion of lithium metal are effectively inhibited.

The invention relates to the field of sodium ion batteries, and discloses a preparation method and application of an additive induced coordination compound derived Bi nitrogen-doped carbon composite material. The preparation method comprises the following steps: chelating an organic ligand with Bi ions in bismuth salt through a mechanochemical method to obtain a precursor Bi-HMT; subsequently, mixing and grinding the precursor and an additive to obtain an intermediate product, and performing high-temperature pyrolysis and carbon thermal reduction on the intermediate product to obtain a final product Bi nitrogen-doped carbon composite material. When the material is used as a sodium ion battery negative electrode, a nitrogen-doped carbon skeleton generated based on in-situ conversion of a coordination compound and an additive can be tightly combined with Bi particles, agglomeration among the Bi particles is avoided, volume change caused by intercalation and deintercalation of sodium ions is effectively relieved, heteroatom nitrogen is introduced through an organic ligand to modify the carbon skeleton, and the specific surface area of the material is increased. The chemical affinity of the material is improved, the overall conductivity of the composite material is improved, and the cycling stability and the rate capability of the material are enhanced.

This invention relates to the field of dry electrode fabrication technology, specifically a method for preparing a silicon anode dry electrode for sulfide solid-state batteries. In a glove box, any two of the following raw materials—pre-lithiated silicon, silicon powder, and a binder—are placed in a ball mill jar, sealed, transferred, and fixed on a rotating support within the ball mill. The ball mill then performs its first cycle. After the mill stops, the jar is removed and transferred back to the glove box. Inside the glove box, the jar is opened and removed to obtain a primary mixture. A binder is added to the primary mixture, and the ball mill cycle is repeated to obtain a secondary mixture. This invention achieves carbon coating on the surface of pre-lithiated silicon and silicon, mitigating the volume expansion of the silicon anode during charging and discharging, maintaining the high ionic conductivity of the sulfide electrolyte, and achieving the preparation of a high-silicon-to-content, high-energy-density silicon anode through dry electrolysis.