51 results about "Decomposition potential" patented technology

The invention belongs to the field of lithium ion batteries, and discloses a ZIF-67-derived composite lithium oxalate lithium supplement agent and a preparation method and application thereof.The lithium supplement agent comprises a lithium oxalate matrix and a ZIF-67-derived Co-based catalyst, and the ZIF-67-derived Co-based catalyst is evenly distributed on the surfaces of lithium oxalate particles or among crystals to form a composite structure; a water-phase synthesis method is adopted for preparation, ZIF-67 is converted into Co-based nano-particles, the Co-based nano-particles and lithium oxalate particles form a composite structure, the Co-based nano-particles can serve as a positive electrode additive to be applied to a positive electrode of a lithium ion battery, in-situ thermal decomposition / electrolytic reaction occurs in the first charging process of the battery, Li is released to compensate irreversible capacity loss, the decomposition potential can be reduced to 4.0 V or below, and the positive electrode additive can be applied to the positive electrode of the lithium ion battery. The first-time charging efficiency is improved to 90% or above, and the cycling stability is remarkably enhanced.

A lithium replenishment composite material and its preparation method, as well as a positive electrode plate, a separator, a secondary battery, and an electrical device. The composite material includes a core and a coating layer containing a conductive material, which at least partially covers the core. The core comprises a lithium replenishment agent and a metal catalyst, wherein the lithium replenishment agent includes an organic lithium compound. During an initial charging cycle, the organic lithium compound releases lithium ions to replenish lithium in the negative electrode, while its byproducts decompose into gases that are expelled from the battery, thereby minimizing impact on mass energy density and long-term performance. The metal catalyst lowers the decomposition potential of the lithium agent, allowing lithium replenishment at lower voltage while protecting the positive electrode and electrolyte. The conductive coating suppresses metal dissolution, enhances conductivity, and improves the cycling performance of the battery.

The invention belongs to the field of sodium-ion batteries, and discloses a sodium-ion battery electrolyte and a sodium-ion battery. The sodium-ion battery electrolyte comprises sodium salt, an organic solvent and an organic molecular additive shown in the following formula, wherein R1 to R5 are respectively and independently any one of F, Cl, Br, I, CN, H, OH, SH and NO2. A boron atom in the molecular structure of the additive is used as an electron-deficient center and can be preferentially complexed with anions or solvent molecules in the electrolyte to pre-stabilize an electrode interface; the bond energy of the B-O bond is moderate, so that the oxidation potential of the B-O bond is lower than that of a main body carbonate solvent, the B-O bond can be preferentially decomposed in the first charge-discharge process, and a thin, compact and highly stable positive electrode electrolyte interface film is formed on the surface of a positive electrode; the controllable substituent group on the benzene ring further regulates the decomposition potential of molecules through an electronic effect, so that the film forming time and the film property can be precisely regulated and controlled. The stable CEI can effectively inhibit continuous decomposition of the electrolyte at high temperature and high pressure, and the cycling stability of the battery in the high-temperature and high-pressure environment is remarkably improved.

The invention discloses a nanoscale lithium oxalate / carbon composite lithium supplement agent, a preparation method and application of the nanoscale lithium oxalate / carbon composite lithium supplement agent in a lithium ion battery. The lithium oxalate powder is prepared into the lithium oxalate saturated aqueous solution, then the amphiphilic surfactant is added, overgrowth of crystals of the lithium oxalate in the drying process can be limited, the particle size of the lithium oxalate is effectively reduced, and therefore the ion transmission path is shortened. Besides, after the carbon material is added, the polar group of the amphiphilic surfactant promotes the uniform distribution of the carbon material, so that a three-dimensional conductive network structure is constructed, the electron transmission path is effectively shortened by the structure, and the conductivity of the material is remarkably improved. The lithium supplement agent prepared by the invention has remarkable electrochemical performance, and the decomposition potential of the lithium supplement agent is successfully reduced to about 4.33 V, which conforms to the working voltage range of a positive electrode material and an electrolyte of a commercial lithium ion battery. The method provided by the invention has the advantages of simple operation and no need of additional introduction of a metal catalyst, and can effectively reduce the raw material cost.

The invention discloses a composite lithium supplementing material and a preparation method thereof, a positive electrode, a lithium ion battery and a power utilization device, the composite lithium supplementing material comprises a conductive substrate and lithium supplementing agent crystal particles attached to the surface of the conductive substrate, and the Dv50 particle size of the lithium supplementing agent crystal particles is less than 100 nm. Lithium supplement agent crystal particles are formed on the surface of the conductive substrate through recrystallization, the smaller lithium supplement agent crystal particle size (less than 100nm) provides more reaction sites and shortens the lithium ion transmission path, and meanwhile, the conductive effect of the conductive substrate further improves the electrochemical decomposition kinetics of the lithium supplement agent, so that the decomposition potential of the lithium supplement agent is reduced, and the lithium supplement effect is improved. For example, the decomposition potential of lithium oxalate can be reduced from about 4.90 V to 4.35 V or below, so that the lithium oxalate is compatible with an existing lithium ion battery.

This application provides a secondary battery and an electrical device, relating to the field of lithium battery technology. On one hand, this application utilizes a second positive electrode active material for positive electrode lithium replenishment to improve the cycle performance of the secondary battery. On the other hand, because the carbon layer on the surface of the second positive electrode active material has a certain catalytic effect on phosphate ester film-forming additives, it can reduce the decomposition potential of phosphate ester film-forming additives on the surface of the second positive electrode active material. This results in some phosphate ester film-forming additives preferentially forming a CEI film on the surface of the second positive electrode active material at a lower voltage, effectively suppressing the active sites of the carbon layer and inhibiting side reactions between the second positive electrode active material and the solvent at lower voltages. The remaining phosphate ester film-forming additives preferentially form a CEI film on the surface of the first positive electrode active material before solvent decomposition during formation, isolating the solvent from contact with the first positive electrode active material, suppressing side reactions, and improving cycle performance.

This invention belongs to the technical field of sodium-ion battery electrode materials, specifically relating to a preparation method and application of an air-stable molten asphalt-coated sodium selenide composite cathode sodium replenisher. The invention first prepares pure-phase sodium selenide nanoparticles in a glove box by room temperature stirring. Then, asphalt is grown in situ on the surface of the sodium selenide through ball milling and high-temperature calcination, thereby forming a core-shell structured sodium selenide composite sodium replenisher material coated with molten asphalt. The resulting composite sodium replenisher is stable in air for extended periods without deterioration, while simultaneously reducing the decomposition potential of sodium selenide and improving its decomposition efficiency. Coupled with a layered oxide cathode, it can achieve cathode sodium replenishment, compensating for the loss of active sodium caused by the growth of the SEI film on the surface of the hard carbon anode. Furthermore, its decomposition product, selenium, can inhibit the lattice oxygen evolution of the layered oxide cathode, improving the structural stability of the cathode and thus effectively enhancing the battery's initial efficiency and cycle performance, demonstrating promising commercial application prospects.

The invention provides an organic lithium salt and a preparation method and application thereof, the organic lithium salt has a structure as shown in a formula I. Through the design of a molecular structure, the organic lithium salt has high capacity and excellent stability, does not generate adverse side reaction in air, solvent and other environments, and is low in decomposition potential and high in stability. The lithium supplement agent can be compatible with various battery systems and manufacturing processes, products obtained after decomposition / lithium removal can enter electrolyte, the positive effect on the cycle performance of the battery is achieved, and the lithium supplement agent is excellent in comprehensive performance. The organic lithium salt is used in a lithium ion battery, is especially suitable for being used as a positive electrode lithium supplement agent to prepare a positive electrode plate, and can significantly improve the capacity and cycle performance of the battery.

The present application relates to a kind of decomposable organic lithium salt for positive electrode lithium supplement agent and its preparation method.Compared with the currently commercialized positive electrode lithium supplement additive, the decomposable organic lithium salt of the present application has the advantages of high theoretical capacity, high air stability, simple preparation process, etc.The lithium salt is prepared by the reaction of a specific precursor and lithium source, and the theoretical capacity and decomposition potential of the lithium salt can be changed by changing the R group of the precursor, and an organic decomposable lithium salt lithium supplement agent is prepared by mixing with conductive carbon.The lithium supplement agent can be added to the positive electrode slurry during battery manufacturing process, and is compatible with the current battery manufacturing process.The lithium salt anion decomposes during charging and does not remain in the positive electrode, ensuring the energy density of the battery.The small molecules generated by decomposition form a solid electrolyte membrane (SEI) rich in inorganic components with the negative electrode, enhancing the mechanical strength of the SEI and prolonging the service life of the battery.

The application relates to the technical field of lithium battery diaphragm, in particular to a modified PE diaphragm with low decomposition voltage and high lithium supplement capacity and a preparation method thereof. The preparation method comprises the following steps: mixing C3N4, a molybdenum source, a cobalt source and citric acid to obtain a precursor; sintering the precursor under a protective atmosphere to obtain a composite catalyst; mixing the composite catalyst, a conductive agent, a binder, lithium oxalate and a solvent to obtain a slurry; and coating the slurry on the surface of a PE diaphragm to obtain the modified PE diaphragm with low decomposition voltage and high lithium supplement capacity after drying. The composite catalyst is obtained by sintering a multiphase precursor, the slurry is mixed with a conductive agent, a binder, lithium oxalate and the like, and is coated on the PE diaphragm, so that the decomposition potential of lithium oxalate can be greatly reduced, the problem that lithium oxalate is difficult to supplement lithium efficiently in a ternary positive electrode system can be effectively solved, the specific capacity of lithium oxalate released at low voltage can be improved, and the effect of high lithium supplement capacity is achieved.

In a first aspect, the present disclosure relates to a method of forming a battery cell, the method comprising:-in a battery cell, the battery cell comprising a carbon-containing anode, a sodium-containing cathode and an electrolyte solution comprising an alkali metal bis (oxalato) borate and an organic solvent wherein the alkali metal ions are selected from sodium (Na +) and potassium (K +), the organic solvent comprises a pyrrolidone and / or phosphate compound,-performing a first formation cycle by fully charging and discharging the battery cell, and-performing a second formation cycle by fully charging and discharging the battery cell; -wherein the formation cycle is from gt; the method is carried out at a temperature in the range of 25 DEG C to 100 DEG C. The present disclosure also relates to a method of forming a battery cell, comprising the steps of:-performing a first step of charging the battery cell at a C-rate in the range of 0.5 C to 20 C; and-performing a second step of constant voltage (CV) charging at a voltage higher than the decomposition potential of the electrolyte salt for a period of time until a C-rate current range of 0.02 C to 4C is reached.

The present invention relates to a composite lithium supplement agent, which is lithium borate doped with a transition metal coated with carbon, and / or lithium thioborate doped with a transition metal coated with carbon. The composite lithium supplement agent of the present invention has a high theoretical decomposition capacity and has ion transport performance, which is beneficial to improving the battery rate performance; and by regulating the doping elements and ratios, as well as carbon coating, a composite lithium supplement agent with two decomposition mechanisms is prepared, significantly improving the electronic conductivity of the material and effectively reducing the decomposition potential; and according to its different decomposition reactions, the charging voltage can be regulated to achieve on-demand lithium supplementation. The composite lithium supplement agent prepared by the present invention has good air stability and moisture resistance, and is compatible with the existing battery preparation process. Moreover, the material has good chemical stability and high safety, and is suitable for industrial-scale preparation.

The invention discloses a lithium ion battery monomer, a lithium ion battery and an electric device, and belongs to the technical field of batteries. The lithium ion battery cell comprises a positive pole piece, the positive pole piece comprises a positive pole film layer, the positive pole film layer comprises a positive pole active material, and the positive pole active material comprises a lithium transition metal oxide; the electrolyte comprises a carboxylic ester solvent and a first additive, and the reductive decomposition potential V1 of the first additive meets the condition of 1.45 Vlt; v1 < = 2V; the shell is used for containing the positive pole piece and the electrolyte, the shell is provided with a pressure relief mechanism, and the actuating pressure P of the pressure relief mechanism is larger than or equal to 0.5 MPa and smaller than or equal to 1.8 MPa. According to the technical scheme, the fast charging performance, the cycle life and the storage life of the battery monomer can be improved.

A composite lithium supplementing material and a preparation method therefor, a positive electrode sheet, a battery, and an electrical apparatus, relating to the technical field of batteries. The composite lithium supplementing material comprises core-shell structure particles, each core-shell structure particle comprising an inner core, and a shell wrapping the outer surface of the inner core. The shell comprises a lithium supplementing agent, and the inner core comprises a reducing agent. The reducing agent comprises at least one of elemental sulfur, elemental boron, lithium sulfide, sodium sulfide and selenium disulfide. By means of forming the lithium supplementing agent and the reducing agent into core-shell structure particles, lithium supplementing efficiency is improved. The lithium supplementing agent is a shell and the reducing agent is a core. Placing the reducing agent in a lithium supplementing agent shell enables the reducing agent to better react with the lithium supplementing agent, and decreases the decomposition potential of the lithium supplementing agent; in addition, the reducing agent can also be combined with anions in the lithium supplementing agent, to generate a stable salt and avoid gas generation. Furthermore, the reducing agent is coated inside the lithium supplementing agent, which can prevent side reactions caused by direct contact between the reducing agent and the electrolyte.

The invention provides a battery assembly which is characterized by comprising a cation supplementing agent, and the decomposition potential of the cation supplementing agent is smaller than or equal to 5V. When the battery assembly is applied to a secondary battery, the cation supplementing agent is decomposed during charging and discharging, so that cations can be provided in a battery system. When the content of cations is increased, the transmission of lithium ions is promoted, so that the attenuation of the battery capacity can be reduced, and the capacity retention ratio of the battery is improved.

An electrolyte (105), a lithium-ion battery (100), an electric device, and an energy storage system. The electrolyte (105) is suitable for a lithium-ion battery (100) comprising a lithium supplementing agent; the electrolyte (105) comprises an organic additive; the organic additive can be dissolved in the electrolyte (105); the oxidation-reduction potential of the organic additive is greater than the decomposition potential of the lithium supplementing agent. The organic additive can promote decomposition of the lithium supplementing agent and effectively reduce the decomposition potential of the lithium supplementing agent, thereby achieving the purpose of compensating for lithium loss of the lithium-ion battery. Moreover, the organic additive is easily dissolved in the electrolyte (105), diffuses to the surface of the lithium supplementing agent along with the electrolyte (105), and is in full contact with the lithium supplementing agent, thereby fully reducing the decomposition potential of the lithium supplementing agent, and increasing the utilization rate of the lithium supplementing agent.

The invention discloses a modified lithium supplement agent and a preparation method and application thereof, and belongs to the field of lithium ion battery positive electrode materials. The lithium supplement agent is of a porous net structure and comprises lithium oxalate, conductive carbon and an additive, the additive takes carbon as a substrate, and Mn-Mo bimetal ions are loaded on the substrate. The mass ratio of the metal Mn to the metal Mo is (1-3): 1. The mass ratio of the additive to the conductive carbon is (0.5-5): 1. The preparation method of the modified lithium supplement agent comprises the following steps: (1) placing a carbon material in strong acid, and carrying out modification treatment to obtain a modified carbon material; (2) impregnating the modified carbon material with manganese salt and molybdenum salt, and sintering to obtain an additive with manganese and molybdenum loaded on the carbon material; and (3) adding conductive carbon and an additive into the lithium oxalate solution, spraying, and drying to obtain the modified lithium supplement agent. According to the modified lithium supplement agent prepared by the method, the lithium oxalate decomposition potential is remarkably reduced, and the overall electrochemical performance is excellent.

The invention belongs to the technical field of sodium ion batteries, and particularly relates to an efficient sodium formate composite positive electrode sodium supplementing agent and preparation and application thereof. According to the preparation method, firstly, iron cluster catalyst particles are prepared through high-temperature calcination, then sodium formate grows on the surface of the catalyst in situ through an anti-solvent crystallization method, the composite sodium supplementing material is formed, and the composite structure can synchronously achieve reduction of the decomposition potential of sodium formate and improvement of the decomposition efficiency. Meanwhile, after the composite sodium-supplementing material is coupled with a layered oxide positive electrode, an efficient positive electrode sodium-supplementing effect can be played, active sodium loss caused by formation of a hard carbon negative electrode SEI film is made up, the first effect and the cycle performance of the battery are improved, and nearly 100% decomposition efficiency can be achieved. The molecular catalytic coupling size control effect is originally created, the sodium supplementing performance of sodium formate is remarkably improved, after the sodium formate is applied to a layered oxide positive electrode hard carbon negative electrode battery system, the first effect and the cycle performance of a battery are effectively improved, and good commercial application prospects are achieved.

This invention relates to a method for preparing lithium nitride. By ball milling the initial lithium nitride material in a mixed atmosphere of nitrogen and argon in a specific ratio, the mass ratio of α-Li3N to β-Li3N in lithium nitride can be controlled within the range of (95-60):(5-40), thereby reducing the reactivity of lithium nitride itself and improving its stability in air. At the same time, when lithium nitride is added as a positive electrode lithium replenishment additive in the positive electrode material of lithium-ion batteries, lithium nitride exhibits the characteristics of low decomposition potential and high decomposition rate during the first charge cycle. Only a very small amount of lithium nitride is needed to compensate for the active lithium consumed during the formation of the SEI film. Lithium nitride has high compatibility and lithium replenishment performance in the positive electrode material of lithium-ion batteries.

The present invention discloses an in-situ gelled double cross-linked polymer electrolyte, a preparation method and an application thereof. A polymer nanofiber membrane is prepared by an electrostatic spinning method, a cross-linked nanofiber membrane is obtained by heat treatment, and then a mixed solution of an organic electrolyte and a cross-linking agent is impregnated to obtain a double cross-linked polymer solid electrolyte membrane material through in-situ cross-linking gelation. The double cross-linked polymer solid electrolyte membrane material has high porosity, high liquid absorption rate, excellent mechanical strength and thermal stability, and good electrochemical properties. It has high ionic conductivity and lithium ion transfer number, high oxidative decomposition potential, and has excellent rate performance and cycle performance when used in lithium-ion batteries, thus solving the problems of low ionic conductivity and poor mechanical properties of polymer electrolytes.

The invention discloses a composite lithium supplement material and a preparation method thereof, a positive pole piece, a battery and an electric device. The composite lithium supplement material comprises core-shell structure particles, each core-shell structure particle comprises an inner core and an outer shell coating the outer surface of the inner core, and the outer shell comprises a lithium supplement agent; the inner core comprises a reducing agent, and the reducing agent comprises at least one of elemental sulfur, elemental boron, lithium sulfide, sodium sulfide and selenium disulfide. The lithium supplementing agent and the reducing agent form the core-shell structure particles, so that the lithium supplementing efficiency is improved. Wherein the lithium supplementing agent serves as a shell, the reducing agent serves as a core, the reducing agent is placed in the lithium supplementing agent shell, it is guaranteed that the reducing agent can effectively react with the lithium supplementing agent, the decomposition potential of the lithium supplementing agent is reduced, meanwhile, the reducing agent can be combined with anions in the lithium supplementing agent, stable salt is generated, and gas is avoided. And moreover, the reducing agent is coated by the lithium supplementing agent, so that side reaction caused by direct contact between the reducing agent and the electrolyte can be avoided.

The invention provides a lithium supplement agent and a preparation method thereof, a positive plate and a lithium ion battery, and relates to the technical field of batteries. The lithium supplement agent provided by the invention comprises lithium-rich lithium ferrite; the surface of the lithium-rich lithium ferrite is coated with carbon nanotubes and silicon carbide; the mass ratio of the carbon nano tube is 0.01%-0.5%; the mass ratio of the silicon carbide is 0.01%-1%. The lithium supplement agent can reduce the internal resistance of the battery, improve the liquid absorption rate of a battery positive pole piece to electrolyte, reduce the decomposition potential, reduce the side reaction of a battery cell, improve the rate capability and cycle performance of the battery cell, reduce the crushing of a lithium supplement agent core body, and avoid the side reaction of lithium supplement agent residues and the electrolyte.

A positive electrode sheet, a preparation method therefor, a battery and an electrical device. The positive electrode sheet comprises a positive electrode active material layer; and a capacity compensation layer, the capacity compensation layer being arranged on a side of the positive electrode active material layer, the capacity compensation layer comprising a catalyst and a capacity compensator, and the average particle size of the capacity compensator being less than or equal to 2 μm. Thus, the present application increases the probability that the catalyst is in contact with the capacity compensator, reduces the decomposition potential of the capacity compensator, increases the capacity retention rate of a battery, and prolongs the service life of the battery.

The invention discloses a sodium ion battery metal oxide catalysis organic nanometer sodium supplement agent, a positive electrode material and a battery, wherein the formula comprises the following components in percentage by mass: 0.5-1% of organic micron sodium salt, 0.01-0.5% of conductive material and 0.1-50% of metal oxide, and the particle size of the organic micron sodium salt is 200-500 microns. The metal oxide catalyzed organic nano sodium supplement for the sodium-ion battery can remarkably reduce the decomposition potential of a sodium supplement composite material, and improve the charge-discharge capacity, the first-circle coulombic efficiency and the cycle stability of the high-voltage sodium-ion battery.

The application discloses an electrochemical preparation method of large-size graphene, which comprises the following steps: under the protection of inert gas, a three-electrode system is adopted, the potential in an electrolyte is increased from the lowest potential of ion intercalation to the highest potential of ion intercalation, a graphite intercalation compound is prepared, then the graphite intercalation compound is peeled off by constant potential electrolysis at an ion decomposition potential, and finally the large-size graphene is prepared. The graphene prepared by the method has a size of 10 microns, low oxidation degree and few defects, and can be applied to MOS devices.

The invention discloses a secondary battery, a capacity compensation agent, a preparation method of the capacity compensation agent and electric equipment, the secondary battery comprises a positive pole piece, a negative pole piece and an isolating membrane, the positive pole piece comprises a positive current collector and a positive membrane layer located on at least one side of the positive current collector, the positive membrane layer comprises the capacity compensation agent, and the capacity compensation agent is located on at least one side of the negative current collector. The capacity compensation agent comprises a compound shown as a formula 1: R-COOM formula 1, R comprises an electron donating group, and M comprises one or two of Na or Li; the volume average particle size Dv50 of the volume compensating agent meets the condition that Dv50 is less than or equal to 4 microns. Therefore, the decomposition potential of the capacity compensation agent is reduced, and the capacity compensation effect is improved.

The application discloses a positive electrode sheet and a preparation method therefor, and a battery and an electric device. The positive electrode sheet comprises a positive active material layer; and a capacity compensation layer arranged on one side of the positive active material layer, wherein the capacity compensation layer comprises a catalyst and a capacity compensation agent, the average particle size of the capacity compensation agent is less than or equal to 2 mu m, and the average particle size of the catalyst is less than or equal to the average particle size of the capacity compensation agent. In this way, the probability of contact between the catalyst and the capacity compensation agent is improved, the decomposition potential of the capacity compensation agent is reduced, and the capacity retention rate and the service life of the battery are improved.

The application belongs to the technical field of energy storage batteries, and discloses a composite nano organic lithium supplementing agent, a preparation method thereof and a positive electrode sheet. The composite nano organic lithium supplementing agent is composed of an active lithium source, a catalyst, a conductive network material and various auxiliary additives, and through precise control of the proportion of each component and the preparation process, the supplementing performance of lithium is optimized. The preparation of the active lithium source at a specific pH value can control the nucleation and growth process kinetics of the active lithium source, and at the pH value, the spray drying process can ensure the precipitation of spherical nanoparticles, and can provide sufficient recyclable lithium. The catalyst uses the ligand-metal charge transfer principle to reduce the oxidation decomposition potential of the unsaturated C=O bond in the carboxylate of the active lithium source. The conductive network material constructs an efficient electron transport path, and the dispersibility, stability and mechanical properties of the lithium supplementing agent are optimized through auxiliary additives. The composite nano organic lithium supplementing agent has excellent mechanical properties, good decomposition kinetics and good conductive performance, and can fully supplement lithium. After being applied to a lithium ion battery, the composite nano organic lithium supplementing agent can significantly improve the initial coulomb efficiency, energy density and cycle stability of the battery, and is suitable for new system batteries such as high-voltage positive electrode materials and silicon-based negative electrodes.

The application belongs to the field of lithium ion batteries, and discloses a ZIF-67 derived lithium oxalate lithium supplementing agent, a preparation method and application thereof. The lithium supplementing agent comprises a lithium oxalate matrix and a ZIF-67 derived Co-based catalyst. The ZIF-67 derived Co-based catalyst is uniformly distributed on the surface or intercrystalline of the lithium oxalate particles to form a composite structure. The preparation adopts an aqueous phase synthesis method to convert the ZIF-67 into Co-based nanoparticles and form a composite structure with the lithium oxalate particles. The lithium supplementing agent can be applied to a lithium ion battery positive electrode as a positive electrode additive. In the first charging process of the battery, in-situ thermal decomposition / electrolysis reaction occurs to release Li+ to compensate for irreversible capacity loss. The decomposition potential can be reduced to below 4.0 V, the first charging efficiency is increased to above 90%, and the cycle stability is significantly enhanced.

The invention discloses a boron-based electrolyte for a rechargeable magnesium battery and application of the boron-based electrolyte. The electrolyte consists of a solvent and a solute, the solvent is organic ether; the solute is composed of organic boric acid ester and alkyl magnesium halide; wherein the concentration of the alkyl magnesium halide in the electrolyte is 0.1 mol / L-2mol / L, and the molar ratio of the organic boric acid ester to the alkyl magnesium halide is 1: (1-3). The electrolyte is applied to the rechargeable magnesium battery, the anodic oxidation decomposition potential can reach 3.5 V vs.Mg or above, and the efficiency is kept 99% or above in the stable cycle process; the electrolyte has the advantages of being simple to prepare, low in raw material cost, high in magnesium deposition-dissolution efficiency and high in anodic oxidation decomposition potential.