53 results about "Sodium supplements" patented technology

The invention relates to the technical field of battery sodium supplementation agents, in particular to a sodium supplementation agent with a core-shell structure, a preparation method and a positive pole piece. The preparation method comprises the following steps: providing a core material containing sodium salt; a first coating process: providing a first coating material containing organic fluorine, mixing the core material containing the sodium salt with the first coating material, and performing first sintering to obtain a primary coating coated with a first coating layer; and a second coating process: providing a second coating material containing a carbon source, mixing the second coating material with the primary coating, and carrying out second sintering to obtain the sodium supplement which is coated with a first coating layer and a second coating layer and has the core-shell structure. The invention provides the sodium supplementing agent with the core-shell structure, the preparation method and the positive pole piece, so that the problem of poor sodium supplementing performance of the sodium supplementing agent in the related technology is solved.

The application provides a preparation method of a precursor pre-adsorption sodium-supplemented sodium iron phosphate pyrophosphate positive electrode material, uses hydrated iron phosphate as a precursor, and places the precursor in a sodium salt of an organic weak acid sodium supplement solution for impregnation adsorption, and after drying, is mixed with a sodium source, a phosphoric acid source, a pyrophosphoric acid source and a carbon source, and is sintered in an inert atmosphere to obtain a pre-sodium-supplemented Na4Fe3(PO4)2P2O7 / C material. The application also provides a sodium iron phosphate pyrophosphate positive electrode material prepared by using the above method, and a sodium ion battery comprising the material. By impregnating and adsorbing the sodium salt of the organic weak acid sodium supplement on the industrial precursor of the sodium iron phosphate pyrophosphate, the nanoscale dispersion of the sodium supplement is achieved, the toxicity and high gas production of the traditional sodium supplement are avoided from the root, the process is adapted to the existing industrial production line, the first coulomb efficiency and the cycle stability of the sodium iron phosphate pyrophosphate positive electrode material are effectively improved, and the industrial application is promoted.

The invention discloses a sodium supplementing method of a sodium-ion battery and application of the sodium supplementing method, and belongs to the technical field of sodium-ion batteries. The sodium supplementing method of the sodium ion battery comprises the following steps: adding a sodium supplementing agent into negative electrode slurry to prepare a negative electrode plate; the negative plate is used for assembling a dry battery, and sodium supplementation of the sodium ion battery is completed through baking, liquid injection, positive and negative electrode reverse charging, formation, aging and capacity grading. According to the invention, a mode of combining negative electrode sodium supplement and reverse charging is adopted, a proper sodium supplement agent is introduced into the negative electrode slurry, and then the sodium supplement agent can be fully decomposed and released through reverse charging, so that the number of freely shuttling sodium ions in the sodium-ion battery is increased, the battery capacity is improved, and finally the energy density of the battery is improved; the steps are simple, meanwhile, the problem of dead quality caused by sodium supplement residues in an existing sodium supplement technology is solved, the process compatibility is good, and industrial application can be achieved.

The application provides a preparation method of a sodium supplement agent with high conductivity, comprising the following steps: S1) soaking bacterial cellulose in a sodium carbonate solution, and then freeze-drying to obtain product A; S2) calcining the product A in a protective atmosphere to obtain product B; and S3) mixing an aqueous oxalic acid solution with the product B, and then standing to obtain the sodium supplement agent. Compared with the prior art, the sodium supplement agent prepared by the method can supplement the consumption of sodium ions in the positive electrode material in the circulation process, and the sodium supplement agent has excellent controllability as the porous carbon carrier can effectively improve the conductivity of the sodium supplement agent as a skeleton, the high conductivity improves the DCR of the sodium ion battery, improves the kinetic performance, and thus improves the electrochemical performance of the sodium ion battery.

A sodium supplement material, a preparation method thereof, positive electrode plate, and sodium-ion battery. The sodium supplement material includes a sodium supplement agent body and first particles exposed on the surface of the sodium supplement agent body. In any 300 nm×200 nm region on the surface of the sodium supplement material, the number of first particles ranges from 2 to 20. The first particles include one or more conductive agent particles and one or more catalyst particles.

The present application relates to the field of battery, especially to a gradient pore hierarchical nitrogen-doped carbon-coated composite sodium supplement agent and its preparation method and application, comprising: a composite sodium supplement agent core and a coating layer coated on the surface of the composite sodium supplement agent core; wherein the composite sodium supplement agent core comprises: an inorganic sodium supplement phase and an organic sodium supplement phase; the coating layer comprises from inside to outside: an inner dense amorphous carbon layer, a middle mesoporous carbon layer and an outer macroporous carbon layer. The present application innovatively designs a gradient pore carbon coating structure from inside to outside, the inner dense amorphous carbon layer realizes efficient isolation protection, the middle mesoporous carbon layer solves the problem of ion transmission obstruction, and the outer macroporous carbon layer improves the electronic conduction and volume buffering capacity, completely solving the inherent contradiction between the denseness of the traditional carbon coating layer and ion transmission, realizing the synergy and unity of "isolation protection-ion transmission-electronic conduction".

The invention belongs to the technical field of sodium ion batteries, and particularly relates to a composite sodium supplement additive which comprises the following raw material components: disodium iminodiacetate, conductive porous carbon and a metal oxide quantum dot catalyst, the metal oxide quantum dot catalyst is coated with the disodium iminodiacetate active particles, and the disodium iminodiacetate active particles are adsorbed on the inner wall and the outer wall of the conductive porous carbon to form the composite sodium supplement additive, and the particle size of the composite sodium supplement additive is 1-500 nm. The composite sodium supplement additive takes conductive porous carbon as a load matrix; the conductive porous carbon comprises any one or more of activated carbon, carbon nanotubes, ordered mesoporous carbon and bamboo charcoal. The active ingredients in the composite sodium supplement agent are small in particle size, good in conductivity and low in decomposition voltage, and an excellent sodium supplement effect can be achieved under the condition of low addition.

The invention discloses a current collector, a secondary battery and a power utilization device, and belongs to the technical field of batteries, the current collector comprises a polymer layer and a matrix layer located on at least one surface of the polymer layer, through holes are formed in the matrix layer, the polymer layer comprises an active ion supplement, and the active ion supplement is formed in the matrix layer. The active ion supplement comprises at least one of a lithium supplement agent and a sodium supplement agent, and active ions generated by decomposition of the lithium supplement agent or the sodium supplement agent can enter the through holes and enter the pole piece (the positive pole piece and / or the negative pole piece) to form a film, so that the loss of the active ions (lithium or sodium) for pole piece film formation is reduced, and the film formation efficiency is improved. And by-products (such as gas) generated by the active ion supplement are discharged from the end surface (side surface) of the polymer layer or are left in the polymer layer, so that the influence on the internal resistance of the pole piece is small, the risk of causing the side reaction of the positive and negative poles is reduced, and the energy density and the cycle life of the secondary battery can be remarkably improved.

The invention belongs to the technical field of sodium ion battery materials, and particularly relates to a sodium-containing modified polyvinylidene fluoride binder as well as a preparation method and application thereof. The sodium-containing modified polyvinylidene fluoride binder comprises a sodium-containing functional unit-polyvinylidene fluoride copolymer, alkannin and a lophatherum gracile polysaccharide stabilizer, wherein the alkannin is grafted on the surface of the sodium-containing functional unit-polyvinylidene fluoride copolymer; the sodium-containing functional unit is combined with a polyvinylidene fluoride main chain through covalent bond grafting. According to the preparation method, the sodium-containing functional unit-polyvinylidene fluoride copolymer is prepared, polyvinylidene fluoride has a bonding function, the sodium-containing functional unit can release sodium ions, compensate sodium loss of the first cycle of the positive electrode and improve the first effect performance, and the sodium-containing functional unit and the polyvinylidene fluoride are connected through a covalent bond to construct a sodium ion conduction channel, so that the conductivity of the sodium ions is improved; meanwhile, a sodium supplementing agent and a conductive polymer with a certain volume are prevented from being introduced into the binder, and the high-activity substance proportion and the binding performance of the binder can be kept.

The invention belongs to the technical field of electrochemical sodium ion batteries, and discloses a sodium supplement additive based on a heterostructure and a preparation method and application thereof.The preparation method comprises the following steps that 1, five or more sodium-containing compounds are jointly dispersed in a solvent, and slurry A is obtained after stirring; (2) adding a conductive carbon material or a carbon preparation precursor into the slurry A, and stirring to obtain slurry B; (3) sanding the slurry B to obtain uniformly dispersed slurry C; (4) carrying out spray drying granulation on the slurry C to obtain precursor powder; and (5) in an inert atmosphere, carrying out heat treatment on the precursor powder, and cooling to obtain the sodium supplement additive based on the heterostructure. The sodium-supplementing additive with the heterostructure is prepared by taking five or more sodium-containing compounds as raw materials, performance parameters such as sodium-supplementing capacity and decomposition voltage of the additive can be optimized, and the sodium-supplementing additive is particularly suitable for a positive electrode plate of a sodium-ion battery.

The invention relates to the technical field of batteries, in particular to a sodium ion battery, a preparation method thereof and a power utilization device. The sodium-ion battery provided by the invention comprises an electrolyte, wherein the electrolyte contains a sodium-supplementing sustained-release capsule; the sodium-supplementing sustained-release capsule comprises a sustained-release shell and a sodium supplementing agent, wherein the sodium supplementing agent is accommodated in the sustained-release shell. According to the sodium ion battery provided by the invention, too high concentration of sodium ions in the electrolyte caused by decomposition of a large number of sodium ions in the early-stage charge-discharge cycle is avoided, and in the long-term charge-discharge cycle process, the slow-release shell is slowly decomposed under an electric field and high temperature to release the internal sodium supplementing agent, so that the effect of long-term sodium supplementing can be achieved, and the service life of the sodium ion battery is prolonged. Furthermore, the capacity retention ratio and the performance exertion of the battery after long-term circulation are improved; and the sodium supplementing method is safe, simple, low in cost and convenient for large-scale industrial production.

The application provides a sodium supplement, a sodium ion battery, an electronic device and a preparation method of the sodium supplement, and belongs to the technical field of secondary batteries. The sodium supplement comprises a core and a coating layer. The core comprises a sodium supplement material. The coating layer comprises a carbon material, metal atoms and non-metal atoms, wherein the metal atoms and the non-metal atoms are located in the carbon material; and the metal atoms comprise at least one of noble metal atoms and transition metal atoms. The sodium supplement can effectively reduce its own decomposition gas, avoid the side reaction of the gas with an electrolyte and a sodium-embedded negative electrode material, and thus ensure the improvement effect of the sodium supplement on the energy density and the cycle life of the battery.

The application discloses a composite sodium supplementing agent and a preparation method and application thereof. m A, wherein A is an anion, and m is the number of sodium ions satisfying charge conservation. The composite sodium supplementing agent is added into a positive plate as a battery additive, can realize one-time sodium ion compensation in the first charging and discharging process of the battery, supplement the sodium ions consumed in the irreversible process such as SEI formation in the initial cycle, effectively improve the initial coulomb efficiency and reversible capacity of the battery, and improve the cycle stability, so that the overall electrochemical performance of the sodium ion battery is improved.

The invention provides a diaphragm and a preparation method thereof, a battery, a battery pack and electric equipment, the diaphragm comprises a base membrane and a functional coating located on at least one side surface of the base membrane, the functional coating comprises a sodium supplementing agent, and the sodium supplementing agent comprises aromatic diphenol sodium. According to the invention, the first coulombic efficiency, the low-temperature rate capability, the high-temperature cycle life and other performances of the battery can be improved.

The invention relates to a sodium supplementing agent and a preparation method thereof, a sodium ion battery positive plate and a sodium ion battery, the chemical structural formula of the sodium supplementing agent is NaB (OSiR1R2R3) 3X, R1, R2 and R3 are independently selected from alkyl or phenyl, and X is selected from F or Cl. The oxidation potential of the sodium supplementing agent ranges from 3.5 V to 3.85 V, the sodium supplementing agent is suitable for the working voltage of a current sodium ion battery, and the sodium supplementing effect is excellent. Moreover, in the presence of oxygen, the sodium supplementing agent can react to generate B2O3, SiO2 and NaX, a composite interfacial film composed of B2O3, SiO2 and NaX has excellent thermal stability and certain heat conduction performance, and the high-temperature stability of the sodium ion battery can be remarkably improved.

The invention discloses a metal organic framework-based sodium supplement and a preparation method and application thereof, and the preparation method of the sodium supplement comprises the following steps: S1, dissolving a metal source and 2-sulfonic acid terephthalic acid monosodium salt in a solvent to obtain a precursor solution; and S2, transferring the precursor solution into a reaction kettle, carrying out a heating reaction, collecting a precipitate after the reaction is finished, washing, and drying to obtain the sodium supplementing agent based on the metal organic framework. Sodium ions in the sodium supplementing agent prepared by the method are combined with sulfonate radicals in a ligand through strong electrostatic interaction, so that the sodium ions are fixed in an MOF framework, and in the charging process, the sodium ions and the sulfonate radicals can be dissociated by electrochemical driving force, so that the sodium supplementing agent is formed. The released sodium ions are driven by an external electric field to quickly migrate into an electrolyte through MOF pore channels to participate in battery reaction, and the structure of the sodium supplementing agent is kept stable after the sodium ions are released, so that the sodium ion battery containing the sodium supplementing agent has high initial charging efficiency and excellent cycling stability.

This invention discloses a Na2Se@C composite sodium supplement, its preparation method, and its application. The supplement comprises Na2Se and carbon coated on the surface of Na2Se, wherein the mass percentage of Na2Se is 80wt%–98wt%, and its particle size is 1–10μm. The preparation method includes the following steps: [The text abruptly ends here, so the translation stops.] x O y Selenium source and carbon are dried and purified before pretreatment, where x = 1, 2, y = 0, 2, 3, 4. The pretreated selenium source and carbon are thoroughly mixed, ground, and sieved at a mass ratio of 1:0.1 to 0.5 to obtain a mixture. The mixture is annealed in an inert gas atmosphere, heated to 500-900℃ and held at that temperature, and then cooled to obtain Na2Se@C composite sodium supplement. This invention can solve the problems of gas generation and inert substance residue in the sodium supplementation process of existing sodium supplements. The synthesis method is simple, safe, and efficient, and can improve the energy density of batteries.

The application discloses a sodium supplement modification method for a negative-electrode-free sodium battery and the negative-electrode-free sodium battery. A composite positive electrode sodium supplement agent is added in a positive electrode active material; the composite positive electrode sodium supplement agent is composed of a sodium-rich layered oxide of a sodium ion battery and sodium carbonate; the mass of the composite positive electrode sodium supplement agent is 0.5wt%-10wt% of the total mass of the positive electrode active material; meanwhile, an electrolyte sodium supplement agent is added in an electrolyte; the added amount of the electrolyte sodium supplement agent is 1wt%-4wt% of the total mass of the electrolyte; and the mass ratio of the added amount of the electrolyte sodium supplement agent to the added amount of the composite positive electrode sodium supplement agent is in the range of 0.2-2:1. Through the cooperation of the electrolyte sodium supplement and the positive electrode sodium supplement, the application realizes rapid sodium supplement, continuous sodium supplement and interface optimization, effectively compensates for the irreversible sodium loss in the first charge-discharge process of the negative-electrode-free sodium battery, significantly improves the first coulomb efficiency, the energy density and the cycle stability of the battery, and promotes the large-scale application of the negative-electrode-free sodium battery.

The invention provides a sodium supplementing agent, a sodium ion battery and a preparation method of the sodium supplementing agent, and belongs to the technical field of secondary batteries, and the sodium supplementing agent comprises an inner core and a coating layer. Wherein the inner core comprises a sodium supplementing material and a lithium supplementing material; the coating layer includes a carbon material. The sodium supplementing agent provided by the invention effectively improves the gram volume development and cycle life of the sodium ion battery.

The application provides a sodium-ion battery negative electrode sheet cold spraying sodium supplement device and a sodium supplement method, and relates to the technical field of sodium-ion battery processing. The sodium-ion battery negative electrode sheet cold spraying sodium supplement device comprises a sodium supplement operation table, and the upper surface of the sodium supplement operation table is fixedly connected with a sodium supplement spraying box. In the application, a cold air blower and a first air compressor are started, cold air is pressurized by the first air compressor, and then is delivered to the sodium powder inlet pipeline inside through a first gas pipeline. High-pressure gas blows the sodium powder in the sodium powder inlet pipeline inside to the inside of three sodium powder delivery pipelines. A second air compressor is started, high-pressure air is sent into the gas output main pipeline by the second air compressor, and then is delivered into the three sodium powder delivery pipelines through three second gas pipelines to pressurize and deliver the sodium powder again. Finally, the sodium powder is sprayed out of the multiple sodium powder spraying branch pipelines along with the high-pressure gas, so that the sodium powder is sprayed on the negative electrode sheet to supplement sodium, and the process is efficient and safe.

The invention provides a sodium supplementing agent, a sodium ion battery, electronic equipment and a preparation method of the sodium supplementing agent, and belongs to the technical field of secondary batteries, and the sodium supplementing agent comprises an inner core and a coating layer. Wherein the inner core comprises a sodium supplementing material; the coating layer comprises a carbon material, metal atoms and non-metal atoms, and the metal atoms and the non-metal atoms are located in the carbon material; the metal atoms comprise at least one of noble metal atoms and transition metal atoms. The sodium supplementing agent effectively reduces gas generated by self decomposition, and avoids side reaction of gas, electrolyte and a sodium-embedded negative electrode material, so that the improvement effect of the sodium supplementing agent on the energy density and cycle life of the battery is ensured.

The invention relates to the technical field of sodium-ion batteries, in particular to a novel asphalt sodium-supplementing pore-forming improved hard carbon material as well as a preparation method and application thereof. According to the experiment, nitric acid is used as an oxidizing agent, the raw material asphaltene is oxidized to obtain a hard carbon precursor, sodium azide is used as a sodium-supplementing pore-forming agent, the asphalt is rapidly heated to be subjected to graphitization removal through a micro-plasma synthesis technology, meanwhile, sodium azide is decomposed at high temperature to perform sodium-supplementing pore-forming on asphalt hard carbon, and the effects of reducing graphitization and optimizing pore-forming are achieved; according to the present invention, the sodium supplementing efficiency is improved, the energy consumption is reduced, the negative electrode active material has advantages of high specific surface area and more active sites in the presence of the pore-forming agent, and the assembled battery has advantages of large specific capacity, low first-circle loss rate and the like. The novel asphalt sodium-supplementing pore-forming improved hard carbon material provided by the invention has the advantages of large specific surface area and more active sites, and the assembled sodium ion battery has excellent electrochemical performance.

This invention belongs to the field of sodium-ion battery technology, specifically relating to a composite sodium replenishing agent, its preparation method, and a positive electrode sheet for sodium-ion batteries. The composite sodium replenishing agent provided by this invention includes a fully sacrificial sodium replenishing agent and a non-fully sacrificial sodium replenishing agent. The fully sacrificial sodium replenishing agent has a porous structure, and the non-fully sacrificial sodium replenishing agent is loaded within the porous structure of the fully sacrificial sodium replenishing agent. This invention uses a fully sacrificial sodium replenishing agent with a porous structure as a carrier, which provides structural support. Loading the non-fully sacrificial sodium replenishing agent within the porous structure of the fully sacrificial sodium replenishing agent not only improves the cycle life of the battery cell but also significantly reduces gas production, simplifying the application of sodium replenishing agents.

The invention discloses a preparation method and application of a sodium-rich sodium ferric sulfate positive electrode material, and the preparation method comprises the following steps: weighing sodium sulfate, ferrous sulfate and a phosphorus source according to the stoichiometric ratio of a sodium-poor intermediate compound, dispersing in deionized water, and carrying out ball milling and mixing to obtain slurry; performing spray drying on the slurry to obtain sodium-poor precursor powder; the sodium-poor precursor powder and a sodium supplementing agent are mixed through a dry method and then calcined, and the sodium supplementing agent and the sodium-poor precursor powder are subjected to a solid-phase reaction to obtain the sodium-rich sodium ferric sulfate positive electrode material. According to the method, a step-by-step synthesis process of'primary sodium deficiency and secondary sodium supplement 'is adopted, and a sodium-deficient precursor is synthesized by a wet method, so that the mixing uniformity of raw materials is greatly improved, and composition segregation is avoided from the source; the formed sodium-poor precursor is stable in structure, and an ideal substrate is provided for the sodium supplementing reaction in the second step; sodium ions are uniformly embedded into a crystal structure to form sodium-rich sodium ferric sulfate with accurate stoichiometry during sodium supplementation by a dry method, so that pollution and sodium loss possibly introduced by secondary wet treatment are avoided.

The invention belongs to the technical field of sodium-ion batteries, and particularly relates to a method for pre-embedding sodium into a low-temperature sodium-ion battery. According to the invention, organic sodium borate is used as a sodium pre-embedding agent, and specifically, the sodium pre-embedding agent is used as an additive to be dissolved in the electrolyte of the sodium-ion battery; active sodium ions are released through electrochemical oxidation at a low temperature, so that sodium supplementation is realized; meanwhile, an electrolyte cosolvent component with a low freezing point is generated, excellent electrochemical compatibility is achieved, and the sodium ion battery has excellent sodium supplementing performance and longer cycle life under the low-temperature condition. According to the sodium ion battery subjected to sodium pre-embedding treatment, the sodium ion transmission performance of the sodium ion battery at an extremely low temperature (-60 DEG C) is greatly improved, and the battery efficiency is improved. The sodium pre-embedding agent is high in specific capacity (approximately equal to 179 mAh g <-1 >), high in solubility in an electrolyte and excellent in compatibility with a sodium ion battery system. The sodium pre-embedding process is simple, and industrial application is facilitated.

The application discloses a sodium supplement, a preparation method thereof, a positive plate, a preparation method thereof, and an electrochemical device. The sodium supplement comprises an inner core and a coating layer at least partially covering the inner core. The inner core comprises a sodium source material, and the material of the coating layer comprises a water-absorbing material. The inner core is at least partially covered in the coating layer, so that, in use, when the sodium supplement contacts moisture, the water-absorbing material of the coating layer contacts the moisture first, the moisture is fixed in the water-absorbing material, and the sodium source material of the inner core is covered by the water-absorbing material of the coating layer, thereby reducing the contact between the sodium source material and the moisture, reducing the formation of strong alkaline compounds on the surface of the positive electrode, and weakening the influence on the cycle stability of the battery.

The present application relates to the technical field of energy storage apparatuses, in particular to a sodium-supplement agent, and a positive electrode sheet and preparation method therefor, and an electricity-consumption device. The composite sodium-supplement agent is located on a positive electrode sheet of a sodium-ion energy storage apparatus, and the composite sodium-supplement agent comprises: a first sodium-supplement agent and a second sodium-supplement agent, wherein the first sodium-supplement agent has a first oxidation potential, and the second sodium-supplement agent has a second oxidation potential, the first oxidation potential being smaller than 3.9 V, and the second oxidation potential ranging from 3.9 V to 4.4 V. The composite sodium-supplement agent is disposed on the positive electrode sheet, and therefore the advantages, such as realizing simple operation and processing, reducing treatment procedures and involving no harsh processing conditions, are achieved, and industrial application can be implement. In addition, the composite sodium-supplement agent has a relatively comprehensive sodium supplement function, and can form a certain gradient of oxidation potential, thereby achieving the effect of gradient sodium supplementation. Full-stage sodium supplementation can be performed on a sodium-ion energy storage apparatus from an initial formation stage to a subsequent cyclic charging / discharging stage, such that the electrochemical performance of the sodium-ion energy storage apparatus is improved throughout the whole process from formation to cyclic charging / discharging.

This invention discloses a sodium-ion battery double-layer coated composite sodium replenisher, its preparation method, and its application, relating to the field of new energy battery technology. The sodium replenisher consists of a core composite matrix and a double-layer outer shell. The core composite matrix is ​​αA∙(1-α)D; the double-layer outer shell surrounds the core composite matrix and includes a first coating layer E and a second coating layer G from the inside out. Wherein, A is Na… a Ni x M 1‑x O y D is Na b Π z This invention also discloses a method for preparing the sodium replenishing agent and its application in sodium-ion batteries. This sodium replenishing agent can compensate for the irreversible loss of active sodium in sodium-ion batteries, helping to improve the battery's energy density, increase coulombic efficiency and cycle life, and facilitate the large-scale promotion and application of sodium-ion batteries in energy storage fields requiring more than 10,000 cycles.

The invention discloses a sodium supplement additive of a sodium ion battery and a preparation method and application thereof, and belongs to the technical field of sodium ion batteries. A precursor is prepared through a high-temperature solid-phase method, transition metal with low valence is oxidized into transition metal with high valence in the synthesis process of the precursor, and a basic lattice frame is provided for subsequent synthesis of the sodium supplement additive; no impure phase is generated in the sodium supplementing additive; na2O2 is introduced in the process and can be decomposed to release oxygen in the sintering process, so that the oxidizing atmosphere in the sealed crucible is ensured, and the valence state of Ni < 3 + > is maintained to be stable; the sodium-supplementing additive prepared by the method has lower decomposition voltage and higher irreversible specific capacity, so that more extra capacity can be provided by adding a small amount of the sodium-supplementing additive into the positive electrode of the sodium-ion battery, and the energy density of the sodium-ion battery is remarkably improved.

The application relates to a sodium supplement, a preparation method of the sodium supplement, a sodium supplement positive electrode and a preparation method of the sodium supplement positive electrode and a sodium ion battery. x MO4, wherein x is 3-4.5, the M comprises a first element, the first element is any one or a combination of at least two of Co, Fe, Mn, Cr, Ti, V, Zr, Mo or W; and the sodium supplement is a triclinic crystal structure. The sodium supplement comprises a triclinic crystal structure of Na x MO4, the crystal structure of the sodium supplement is unstable, is easy to decompose at a low voltage, can be matched with most positive electrode materials, the decomposition product is an oxide, has no negative effect on the positive electrode material and has a high theoretical specific capacity, therefore, the sodium supplement is a high-efficiency sodium supplement, has good compatibility with a sodium ion positive electrode active material, and can improve the capacity and cycle stability of the sodium ion battery. x MO4 can be used as a high-efficiency sodium supplement and has good compatibility with a sodium ion positive electrode active material, thereby improving the capacity and cycle stability of the sodium ion battery.