33results about How to "Improve high temperature storage performance" patented technology

This invention provides an electrolyte, a battery, a battery pack, and an electrical device. The electrolyte includes additives, including fluorocarbonate, unsaturated carbonate, a first sulfide additive, a second sulfide additive, and an anhydride additive. The first sulfide additive includes sulfonate compounds; the second sulfide additive includes sulfite compounds and / or sulfate compounds. Based on the mass of the electrolyte, the mass percentage of each component is as follows: fluorocarbonate m1%, 1.5≤m1≤5; unsaturated carbonate m2%, 1.5≤m2≤3; first sulfide additive m3%, 0.5≤m3≤2; second sulfide additive m4%, 0.5≤m4≤2; anhydride additive m5%, 0.3≤m5≤0.8; and satisfies 1≤(m1+m2) / (m3+m4+m5)≤3. This invention can effectively suppress gas generation at high temperatures in the battery and improve the cycle performance and storage performance of the battery under high-temperature conditions.

The application provides an electrolyte and a battery comprising the electrolyte, wherein the diazonium salt compound in the electrolyte can be decomposed in advance to generate a large amount of inert gas before a large amount of organic solvent is volatilized to generate gas during a furnace temperature test, and the inert gas is discharged from the pole lug, so that the generated heat is timely released, heat accumulation in the interior is avoided, and heat runaway is avoided; on the other hand, the volatilization of the organic solvent can cause the ion channel in the battery to be closed, so that the side reaction is stopped, the battery can safely pass the furnace temperature test, and the safety of the battery under the condition of heat runaway is significantly improved. Meanwhile, the electron-deficient B element in the diazonium salt compound in the electrolyte has Lewis acidity, can accept an electron pair, can remove HF in the electrolyte, avoids the damage of HF to the interface protection film, and further improves the high-temperature storage performance of the battery.

To overcome the problem of insufficient high-temperature cycle performance in existing lithium-ion batteries, this invention provides a lithium-ion battery comprising a positive electrode, a negative electrode, and a non-aqueous electrolyte. The positive electrode includes a positive electrode current collector with a conductive coating on its surface and a positive electrode material layer disposed on the positive electrode current collector. The non-aqueous electrolyte includes a non-aqueous organic solvent, a lithium salt, and an additive. The additive includes a compound represented by structural formula 1. The lithium-ion battery satisfies the following condition: and 2.4 ≤ M. A ≤3.6, 0.1≤W A ≤5, 0.1≤d≤10, 3.3≤c≤3.8. The lithium-ion battery provided by this invention can effectively improve high-temperature cycling and storage performance.

The invention discloses a lithium manganate battery and a preparation method thereof. The lithium manganate battery comprises a positive plate, a diaphragm, a negative plate and a functional diaphragm, the functional diaphragm comprises CaO2 and a multi-dimensional conductive carbon material; the functional diaphragm is arranged between the positive plate and the diaphragm, and / or the functional diaphragm is arranged between the negative plate and the diaphragm, HF in an electrolyte is consumed through alkaline compounds in the functional diaphragm, dissolution of manganese in the positive electrode is reduced, but interface impedance can be increased through an interface layer composed of the independent alkaline compounds, so that the performance of the lithium ion battery is improved, and the service life of the lithium ion battery is prolonged. Therefore, in combination with the multi-dimensional conductive material, the porous structure of the multi-dimensional conductive material can adsorb and intercept the dissolved manganese, and meanwhile, the alkaline compound material can be uniformly distributed in a conductive pore channel, so that the damage to the negative electrode is reduced, and the high-temperature cycle and high-temperature storage performance of the battery is improved.

The invention provides an electrolyte and a secondary battery, the electrolyte comprises a solvent, an additive and an electrolyte, the solvent comprises fluoroethylene carbonate, a compound as shown in a formula I and a compound as shown in a formula II, the mass ratio of fluoroethylene carbonate to fluorochain ester is 1: (0.33-4), the mass ratio of the compound as shown in the formula I to the compound as shown in the formula II is 1: (0.33-3), and the additive and the electrolyte are used for preparing the electrolyte. Based on the mass of the electrolyte, the mass percentage A of the fluorinated solvent is more than or equal to 20% and less than or equal to 80%; the additive comprises tetraethylene silane, based on the mass of the electrolyte, the mass percentage of the tetraethylene silane is M, and M is larger than or equal to 0.02% and smaller than or equal to 3%. Through the arrangement, the fluoroethylene carbonate, the compound as shown in the formula I, the compound as shown in the formula II and the tetraethylene silane have a synergistic effect, so that the electrolyte has proper viscosity and relatively high oxidation resistance, and meanwhile, the negative influence of defluorination on a positive electrode can be improved; therefore, the high-temperature cycle performance and the high-temperature storage performance of the secondary battery under the high-pressure condition are improved.

The invention relates to the field of batteries, in particular to a thiophene compound and a preparation method thereof, an electrolyte and a battery. The structural formula of the thiophene compound is as shown in formula I, specifically, the thiophene compound containing cyano and sulfamido is obtained by carrying out electrophilic aromatic amino sulfonylation reaction on a cyano thiophene compound and an amino sulfonyl chloride compound; the electrolyte comprises a solvent, a lithium salt, an additive and the thiophene compound. The electrolyte provided by the invention comprises the thiophene compound containing the cyano group and the sulfamide group, and the thiophene compound not only can participate in film formation of a positive electrode and a negative electrode, but also can be complexed with transition metal ions dissolved out from the electrolyte, so that the high-temperature performance of the battery is synergistically improved.

This invention discloses an electrolyte and its lithium-ion battery, comprising a lithium salt, an organic solvent, and an additive; the additive includes at least compound A, the content of which is 0.5% to 8% of the total weight of the electrolyte; the general structural formula of compound A is as follows: In formula I, at least one of R1, R2, and R3 is an alkoxyalkyl group with 1 to 20 carbon atoms, at least one of which is O-TMS, and the remaining one is selected from one of an alkoxyalkyl group with 1 to 20 carbon atoms, CN-, -CH2C, -CH2CH2CN, -CH2CH2CH2CN, -CH2CH2CH2CH2CN, and O-TMS, wherein TMS is Si-(CH3)3. In this invention, compound A is added to the electrolyte, and the PF5 generated from LiPF6 in the electrolyte reacts with trace amounts of water to generate HF. The HF is cleared by the siloxane functional groups in compound A, wherein the fluoride (F... ‑ ) is captured by silicon (Si) to generate TMSF, H + It is also captured by oxygen (O) to form HPO, thereby improving high-temperature cycling performance and high-temperature storage performance under high voltage.

The invention specifically discloses an electrolyte and a lithium ion battery. The electrolyte comprises an electrolyte for first injection and an electrolyte for second injection, the first injection electrolyte comprises a first solvent, a first additive and a first lithium salt; the first solvent comprises dimethyl carbonate, the first additive comprises vinylene carbonate and a composite additive, and the composite additive comprises at least one of fluoroethylene carbonate, ethylene sulfate and methylene methanedisulphonate; the mass ratio of the dimethyl carbonate is 45%-50%; the secondary injection electrolyte comprises a second solvent, a second additive and a second lithium salt; the second solvent comprises dimethyl carbonate, and the second additive comprises vinylene carbonate; the mass ratio of the dimethyl carbonate is 45%-50%; the mass ratio of the vinylene carbonate is 15%. The lithium battery has the advantages of high energy density and long cycle performance.

The application provides a phosphate-based positive electrode material, a preparation method thereof and a lithium ion battery, and the preparation method comprises the following steps: (1) mixing raw materials of the phosphate-based positive electrode material, a first carbon source and a solvent, and performing drying, crushing and first calcination to obtain one-step calcined particles; (2) mixing a second carbon source and the one-step calcined particles in step (1), and performing heat treatment, wherein the second carbon source is sublimated and adhered to the surface of the one-step calcined particles in the process of the heat treatment, and then performing second calcination to obtain the phosphate-based positive electrode material. The phosphate-based positive electrode material provided by the application is coated with a dense carbon film on the outer surface, and can better isolate the electrolyte and the phosphate-based positive electrode material after forming a lithium ion battery, thereby improving the high-temperature performance of the lithium ion battery.

Provided are an electrolyte additive, an electrolyte for a lithium secondary battery containing the same, and a lithium secondary battery. Specifically, the present application can provide an electrolyte for a lithium secondary battery containing an electrolyte additive including a compound represented by Formula 1, which can effectively suppress the deterioration of a positive electrode and is not easily decomposed on a negative electrode, and a lithium secondary battery containing the same, thereby achieving excellent high-temperature storage characteristics and high-temperature cycle characteristics.

This invention relates to a secondary battery, an electrode wetting method, and a method for preparing the secondary battery. From a product design perspective, this invention reduces the areal density and compaction density of the electrode, increases the number of stacked layers, establishes a correlation between electrode areal density, compaction, and the number of stacked layers and the electrode pore volume, and directionally increases electrode pores to provide channels and storage space for electrolyte penetration. Based on this, the electrolyte formulation is optimized, thereby improving electrolyte wettability and ultimately enhancing the battery's long-term cycle life and high-temperature storage performance.

This invention provides a battery comprising an electrolyte and a negative electrode, wherein the negative electrode active material comprises a silicon-containing material; the electrolyte comprises a first additive and a second additive, the first additive comprising fluoroethylene carbonate, and the second additive comprising a compound having a structure of Formula 1, wherein R1-R3 are each independently selected from substituted or unsubstituted C1-C10 alkyl, substituted or unsubstituted C2-C10 alkenyl, or substituted or unsubstituted C2-C10 alkynyl groups, and at least one unsaturated group is included in R1-R3. The battery provided by this invention uses silicon material as the negative electrode and exhibits excellent room temperature and high temperature cycling performance, as well as high temperature storage performance.

The present application relates to the technical field of lithium ion batteries, in particular to a lithium ion battery and a preparation method thereof. In the present application, the performance index k calculated by the mass fraction of the negative electrode conductive agent in the second negative electrode material layer, the mass fraction of the negative electrode binder in the first negative electrode material layer, the area density ratio of the second negative electrode material layer to the first negative electrode material layer and the mass fraction of the additive lithium difluoro(oxalato)borate in the electrolyte is compared with the set threshold value. The optimization of each mass fraction or area density ratio can provide accurate and quantifiable guidelines for the design of high-performance double-layer negative electrode batteries. Within the set threshold value range, the lithium ion battery with high peeling force (indicating good mechanical stability of the electrode sheet), excellent high-temperature storage performance and super-long cycle life can be obtained.

The application discloses a phosphorus-carbon metal composite negative electrode material, a preparation method and application thereof, and belongs to the technical field of material preparation. The preparation method of the phosphorus-carbon metal composite negative electrode material comprises the following steps: activating and pore-forming of a mixture of a carbon source compound, an activating agent and a molybdenum compound in an activating gas to obtain molybdenum-doped porous carbon; performing gas phase deposition of the molybdenum-doped porous carbon in red phosphorus gas and selenium gas to obtain phosphorus-selenium-molybdenum porous carbon; and performing gas phase deposition of the phosphorus-selenium-molybdenum porous carbon in sulfur vapor and carbon source vapor in sequence to obtain the phosphorus-carbon metal composite negative electrode material. The phosphorus-carbon metal composite negative electrode material utilizes molybdenum selenide and phosphorus to improve the specific capacity of the material, utilizes a porous structure to reduce the expansion of the molybdenum selenide, and utilizes sulfur-doped amorphous carbon deposited on the shell to improve the electronic conductivity of the material, and the application of the material to a sodium ion battery has the advantages of high specific capacity, good rate performance, low expansion and the like, and improved cycle performance.

The application discloses an electrolyte and a lithium ion battery. The electrolyte comprises a mixed solvent of fluorinated carbonate and linear carbonate, a lithium salt, an additive and a stabilizer. The mass ratio of the fluorinated carbonate to the linear carbonate in the mixed solvent is 1:(1-5). The electrolyte has good thermal stability, and the high-temperature decomposition defect of the cyclic carbonate is improved. The lithium ion battery assembled by using the electrolyte has good high-temperature storage performance, and the gas production of the assembled lithium ion battery at high temperature is significantly reduced. The safety performance of the assembled lithium ion battery is greatly improved, and the heat resistance temperature is as high as 160 DEG C. In addition, the battery also has good cycle performance, and when the cycle is 600 times at a current density of 1C, the capacity retention rate can still reach more than 94%.

The invention provides an electrochemical device and electronic equipment, the electrochemical device comprises a positive electrode, a negative electrode and a diaphragm, the diaphragm comprises a base film and a coating layer, the coating layer comprises a first coating layer and / or a second coating layer, the coating surface density of the first coating layer is a g / m < 2 > / mu m, the coating surface density of the second coating layer is b g / m < 2 > / mu m, an electrolyte contains a fluorosulfonamide compound, and the electrolyte contains an electrolyte. The mass content of the fluorosulfonamide compound in the electrolyte is c%, and the binding power efficiency of the electrolyte is M; the following relational expression is satisfied: M = 25% * a + 75% * b; c / M is greater than or equal to 2.67 and less than or equal to 49.52; through the synergistic effect of the coating layers on the two sides of the diaphragm, the cycling stability, the rate capability and the safety of the battery are improved, meanwhile, the lithium dendrite penetration risk is effectively inhibited, and good dimensional stability is kept under the high-temperature condition; by synergistically limiting the coating surface density of the first coating layer and the second coating layer and the mass content of the fluorosulfonamide compound, the cycling stability, the interface compatibility and the high-temperature storage performance of the lithium ion battery can be remarkably improved.

The invention belongs to the technical field of lithium ion batteries, and relates to a cyano electrolyte additive, an electrolyte and a lithium ion battery. The cyano electrolyte additive comprises a nitrile additive and a functional additive; the structural formula of the functional additive is shown in the specification. The nitrile additive and the functional additive are compounded, the functional additive has a cyano group and a triazine ring, the triazine ring is chelated with transition metal ions and cooperates with the cyano group to form a film, and a benzene ring rigid structure can enhance the thermal stability. The nitrile additive and the functional additive have a cyano complementation effect, three phenyl groups in the functional additive are connected with a triazine ring, so that the functional additive has a larger structure and steric hindrance and cannot be completely complexed with transition metal ions on the surface of the positive electrode, and the short-chain nitrile additive has a smaller structure and can make up the space of the functional additive; and the two synergistically form a complementary effect to form a compact interfacial film on the surface of the positive electrode so as to improve the high-temperature performance.

The present application relates to an electrochemical device comprising a positive electrode sheet, a negative electrode sheet, and an electrolyte, the negative electrode sheet comprising a negative electrode active layer, the positive electrode sheet comprising a positive electrode active layer, the positive electrode active layer comprising a positive electrode active material, the positive electrode active layer comprising an aluminum element, wherein a content A (mmol) of the aluminum element in the positive electrode active layer and a total area B (mm 2 ) of the negative electrode active layer satisfy: 3≤A / B≤25, the positive electrode active material comprising lithium manganate and a manganese-containing compound.

The invention provides a secondary battery and electric equipment. The secondary battery comprises a positive pole piece and an electrolyte, the positive pole piece comprises a positive current collector and a positive active material layer arranged on at least one surface of the positive current collector, the positive active material layer comprises a positive active material, the positive active material comprises lithium iron phosphate, and the lithium iron phosphate comprises secondary particles formed by gathering primary particles. The average particle size of the primary particles is D nm, the specific surface area of the lithium iron phosphate is BET m < 2 > / g, and D / BET is greater than or equal to 2 and less than or equal to 30; the electrolyte comprises an additive and an organic solvent, the additive comprises lithium fluorosulfonate, the mass percentage of the lithium fluorosulfonate in the electrolyte is a%, 0.05 < = a < = 0.5, the organic solvent comprises ethyl propionate, and the mass percentage of the ethyl propionate in the organic solvent is greater than or equal to 30%. The low-temperature discharge performance, the high-temperature storage performance and the high-temperature cycle performance of the secondary battery are improved by matching the proper positive electrode active material and the electrolyte.

The invention relates to a high-nickel ternary positive electrode material, a preparation method of the high-nickel ternary positive electrode material, a positive plate and a battery. The high-nickel ternary positive electrode material comprises secondary particles formed by aggregating primary particles, the high-nickel ternary positive electrode material satisfies the following conditions: in the primary particles of the secondary particles, the ratio A [101] / A [104] of the total surface area A [101] of the [101] crystal face to the total surface area A [104] of the [104] crystal face satisfies 0.05 < = A [101] / A [104] < = 0.3; the concentration of the cobalt element in the secondary particle is in gradient distribution which is sequentially decreased from the surface to the center, and the cobalt element concentration C [surface] in the surface area of the secondary particle and the cobalt element concentration C [core] in the core area of the secondary particle meet the condition that (C [surface]-C [core]) / C [core] is larger than or equal to 0.05 and smaller than or equal to 0.2. According to the scheme provided by the invention, the low-temperature discharge capacity, the high-temperature storage stability and the long cycle life of the ternary material can be synergistically improved.

The application provides a single-crystal nickel-cobalt-manganese positive electrode material, a preparation method, a positive electrode sheet and a lithium ion battery. The preparation method comprises the following steps: mixing a nickel-cobalt-manganese precursor, a lithium source and a first additive, first sintering to obtain a first sintered material; mixing the first sintered material and a second additive, second sintering to obtain a second sintered material; mixing the second sintered material and a third additive, third sintering to obtain the single-crystal nickel-cobalt-manganese positive electrode material; the half-peak width a of the (001) crystal face of the nickel-cobalt-manganese precursor and the half-peak width b of the (100) crystal face satisfy the following conditions: 0.30 <= a <= 0.48, 0.38 <= b <= 0.52, and 1.1 <= b / a <= 1.5. The roundness of the single-crystal nickel-cobalt-manganese positive electrode material and the half-peak width of the nickel-cobalt-manganese precursor are combined and quantified, the nickel-cobalt-manganese precursor is screened, and the single-crystal nickel-cobalt-manganese positive electrode material with high roundness and stable structure is prepared by combining the three sintering systems.

The invention relates to the field of negative electrode materials, in particular to a preparation method of an artificial graphite negative electrode material, which comprises the following steps: preparation of a boron nitride precursor: mixing boric acid and a nitrogen source and then adding into a solvent to form a complex; and heating the complex to evaporate the solvent to obtain the boron nitride precursor, first coating: mixing graphitized coke with the boron nitride precursor according to a mass ratio of 100: (1-10) to obtain a first mixture; calcining the first mixture to obtain a first coated product; second coating: mixing the first coating product with a carbon source according to a mass ratio of 100: (0.5-10) to obtain a second mixture; and calcining the second mixture to obtain a second coated product. The negative electrode material prepared by the embodiment of the invention can improve the first efficiency, the high-temperature storage function and the cycle life of the battery.

This invention belongs to the field of secondary batteries, and provides a novel structural additive, a preparation method, a non-aqueous electrolyte containing the novel structural additive, and a secondary battery. The novel structural additive is a complex of an inner salt compound containing a hydrocarbon sulfonate anion and a quaternary ammonium cation with difluorophosphate, having the structure shown in Formula I: where R1 is a hydrocarbon-like group with 1-6 carbon atoms; R2 is a chain-like or cyclic quaternary ammonium cation; R3 and R4 are independently selected from one of , , , , or ; R5, R6, and R7 are independently selected from hydrocarbon groups or hydrocarbon oxygen groups; R8, R9, and R... 10 The elements are independently selected from hydroxyl groups; n=1~6, m=1~6, p=1~6, and n, m, and p are independent of each other; M is a metallic element selected from Li or Na. A non-aqueous electrolyte and a secondary battery containing this novel structural additive are provided, which can improve the battery's low-temperature discharge performance and high-temperature storage performance, and extend cycle life.

The application belongs to the technical field of lithium ion batteries, and relates to a silicon-carbon composite material, a preparation method, a silicon-based negative electrode and a lithium ion battery. The silicon-carbon composite material comprises a core, a carbon coating layer and an aluminum compound coating layer; the core material is elemental silicon and a silicon oxide compound; the core comprises a solid part and a porous layer formed on the surface of the solid part; the carbon coating layer is wrapped on the porous layer; and the aluminum compound coating layer is wrapped on the carbon coating layer. The silicon-carbon composite material has high capacity, stable cycle performance, and superior high-temperature cycle and high-temperature storage performance.

The invention provides a secondary battery and an electronic device, the secondary battery comprises a positive pole piece and an electrolyte, the positive pole piece comprises a positive pole current collector and a positive pole material layer arranged on at least one surface of the positive pole current collector, the positive pole material layer comprises nickel cobalt lithium aluminate, based on the mole number of metal elements except lithium in the positive pole material layer, the molar percentage content of the aluminum element is C1%, and C1 is more than or equal to 2 and less than or equal to 20; the electrolyte comprises a first component, based on the mass of the electrolyte, the mass percentage content of the first component is m1%, and m1 is larger than or equal to 0.01 and smaller than or equal to 5. The secondary battery provided by the invention can give consideration to low-temperature discharge performance, low-temperature cycle stability and high-temperature storage performance.

This application discloses a secondary battery comprising a positive electrode active material layer, which includes a phosphate-based positive electrode material and a lithium-rich manganese-based positive electrode material. The lithium-rich manganese-based positive electrode material includes a substrate material and a coating layer on the surface of the substrate material. The coating layer includes at least one of amorphous carbon and transition metal oxides. Based on the mass of the positive electrode active material layer, the mass content of the substrate material is 1% to 10%, and based on the mass of the substrate material, the mass content of the coating layer is 1% to 12%. This secondary battery, by introducing a lithium-rich manganese-based positive electrode material with a specific structure and content into a phosphate-based positive electrode material such as lithium iron phosphate, can effectively improve gas generation and enhance high-temperature storage performance while maintaining both rate performance and cycle performance.

In order to overcome the problem that the existing lithium ion battery is difficult to consider high temperature performance and low temperature performance, the application provides a non-aqueous electrolyte, which comprises a lithium salt, an additive and an organic solvent, the additive comprises a compound shown in structural formula 1: wherein R1 and R2 are each independently selected from a cyclic carbonate group and a derivative thereof, a cyclic sulfite group and a derivative thereof or a cyclic sulfate group and a derivative thereof, n and m are each independently selected from any natural number of 0-3, and the content of ethanol in the non-aqueous electrolyte is 1-200 ppm. Meanwhile, the application also discloses a lithium ion battery comprising the non-aqueous electrolyte. The compound shown in structural formula 1 provided by the application can not only form a special CEI film at the positive electrode, but also form a SEI film at the negative electrode, so that the lithium ion battery has good low temperature rate performance, high temperature storage performance and high temperature cycle performance.

The application belongs to the technical field of lithium ion batteries, and discloses a ternary high-nickel lithium ion battery nonaqueous electrolyte and a lithium ion battery containing the electrolyte. The ternary high-nickel lithium ion battery nonaqueous electrolyte contains a nonaqueous organic solvent, an electrolyte lithium salt and an additive, the additive contains a sulfur-containing additive and other film-forming additives, the structure of the sulfur-containing additive is shown in formula (I), and the high-nickel lithium ion battery nonaqueous electrolyte is optimized in formula, and under the joint action of a plurality of components in a unique combination, the electrolyte system has high energy density and long service life, and is beneficial to meeting the demand of the electrolyte on cycle performance and high-temperature storage performance in the high-nickel system.

The invention provides an electrolyte and a secondary battery. The electrolyte comprises a solvent, an electrolyte and an additive, wherein the additive comprises a first component and a second component; the first component is selected from fluoroethylene carbonate, the second component is selected from a compound shown as a formula I, based on the mass of the electrolyte, the mass percentage content of the first component is a, a is more than or equal to 5% and less than or equal to 20%, the mass percentage content of the second component is b, and b is more than or equal to 0.1% and less than or equal to 2%. The synergistic effect of the first component and the second component can improve the high-temperature cycle performance, the high-temperature storage performance and the low-temperature discharge performance of the secondary battery and reduce the impedance.

The invention relates to a lithium ion battery electrolyte and a lithium ion battery. The lithium ion battery electrolyte comprises a lithium salt, a solvent and an additive, the solvent comprises a carbonic ester solvent and a carboxylic ester solvent, the carboxylic ester solvent comprises a compound A with a structure shown in a formula I, the additive comprises a film-forming additive, the film-forming additive comprises an anhydride additive, and the anhydride additive comprises a compound B with a structure shown in a formula II. The acid anhydride additive comprises an acid anhydride compound B with a structure as shown in a formula II. By designing the composition of the lithium ion battery electrolyte, the problem of poor cycle performance of the current lithium cobalt oxide lithium ion battery under 5V high voltage is solved, and the high-temperature cycle performance and high-temperature storage performance under 5V high voltage are improved.