523results about How to "Improve high temperature storage performance" patented technology

The invention discloses a lithium ion battery and a positive material, the positive material possesses a core-shell structure, the material of a core layer is at least one of lithium cobaltate, a ternary material and a lithium manganese material, the material of a shell layer is lithium nickel manganese spinel. The preparation method comprises the following steps: preparing the sol shell layer material, then adding the core layer material in the sol, stirring, drying and calcining to prepare the lithium ion battery positive material with the core-shell structure. In addition, the invention also discloses the lithium ion battery prepared by the positive material with the core-shell structure, the end of charge voltage is 4.3-4.7V(vs. Li), the lithium ion battery has excellent charge and discharge cycling performance and high temperature storage performance under high voltage.

The invention discloses a lithium manganese oxide material and a preparation method thereof, in particular to a high-crystallinity lithium manganese oxide material and a preparation method thereof, wherein the high-crystallinity lithium manganese oxide material is used for coating a lithium ion battery. The lithium manganese oxide material is obtained by being coated on a lithium manganese oxide precursor with the one-time crystal particle of 0.01-20mum and has the general formula of LiaMn2-b-cMbGcO4-d-eXdZe, wherein M and X are doped elements, G and Z are coating elements of which the concentration is distributed in a decreasing gradient from outside to inside, a is not less than 0.9 and is not more than 1.2, b is not less than 0 and is not more than 0.2, c is more than 0 and is not more than 0.2, d is not less than 0 and is not more than 0.2, and e is not less than 0 and is not more than 0.2. The material serves as the positive pole material of the lithium ion battery, has better normal-temperature and high-temperature cycle performance and excellent high-temperature storage performance, is simple in preparation and easy to operate, control and carry out industrial production.

The invention discloses an electrolyte solution for a high-capacity lithium-ion battery. The electrolyte solution includes non-aqueous solvent, lithium hexafluorophosphate, negative electrode film forming additive, positive electrode surface activity inhibiting additive and transition metal ion complexant; the negative electrode film forming additive includes organic ester negative electrode film forming additive of 1 to 10wt% of the total electrolyte solution and inorganic lithium salt negative electrode film forming additive of 0.5 to 2wt% of the total electrolyte solution; the positive electrode surface activity inhibiting additive includes fluorinated ether additive of 1 to 5wt% of the total electrolyte solution and nitrile additive of 0.1 to 5wt% of the total electrolyte solution; the transition metal ion complexant is of 0.1 to 1.0wt% of the total electrolyte solution. The electrolyte solution is adaptive to the high-capacity lithium-ion battery and is capable of optimizing the circulating performance and high-temperature storage performance of the lithium-ion battery. The invention further provides a preparation method of the electrolyte solution and the high-capacity lithium-ion battery adopting the electrolyte solution.

The invention provides a silicon-based composite material, which is prepared from silicon particles, silicate and optional carbon, wherein the mixture of the silicate and the optional carbon forms a massive body, and the silicon particles are dispersed in the massive body. A preparation method comprises the following steps of: dispersing the silicon particles into absolute ethyl alcohol and/or deionized water to form suspension liquid; dispersing the silicate and the optional carbon into the absolute ethyl alcohol and/or the deionized water to form suspension liquid; ultrasonically oscillating the two kinds of suspension liquid respectively, and then stirring; dropwise adding the suspension liquid of the silicon particles into the suspension liquid of the silicate and the optional carbon to form mixed liquid, heating and stirring the mixed liquid until evaporating the mixed liquid into paste; then, putting the paste in an oven to be dried to obtain masses, and grinding and sieving to obtain undersize particles; and conducting heat treatment in an inert atmosphere, and grinding and sieving to obtain the silicon-based composite material. According to the silicon-based composite material, a lattice structure of the silicon particles can be ensured, therefore the activity of the silicon particles is ensured, and the energy density, the first-time coulomb efficiency and the high-temperature storage performance of lithium ion batteries are increased.

The invention relates to the technical field of lithium ion batteries, in particular to a ternary cathode material lithium ion battery and an electrolyte thereof. The electrolyte comprises a non-water-based organic solvent, lithium salt and an additive. The additive comprises 1,3-propane sultone, a compound with the structural formula I or II, and a compound containing an M-O-Si functional group. M is any one of B, C, N, P, S and Al. Compared with the prior art, the ternary cathode material lithium ion battery with the electrolyte can normally work within the range of high voltage of 4.4 V or above, rise of internal resistance of the battery is restrained when the battery is used in high-pressure and low-temperature environments, the high-temperature storage performance and a low-temperature discharging platform of the battery are effectively improved, and excellent circulation performance and storage performance can be achieved within the wide temperature range.

The invention discloses an electrolyte additive and an application thereof in a lithium ion battery. The electrolyte additive comprises a polynitrile-based compound and a compound comprising a sulfur bond and an oxygen bond. When the electrolyte additive is applied to the lithium ion battery, good cycle life, good low-temperature discharging property and good high-temperature storage property of the lithium ion battery under the high voltage still can be maintained.

The invention discloses a lithium ion power battery non-water electrolyte. The lithium ion power battery non-water electrolyte is prepared from, by weight, 100 parts of solvents, common lithium salts, 0.2-10 parts of anode film formation additives, 0.2-10 parts of circulation improvement additives and 0.01-0.5 part of acid and water removal additives. The solvents are cyclic carbonic ester and/or chain carbonic ester, and the molar concentration of the common salts in the solvents is 0.8-1.5 mol/L. Due to the combination use of the anode film formation additives, the circulation improvement additives and the acid and water removal additives, during first formation, a CEI film can be formed on the surface of an anode, the stability of a cathode SEI film can be improved, and the normal temperature circulation performance, the high-temperature 45 DEG C circulation performance and the high-temperature storage performance of a power battery can be remarkably improved.

The invention discloses high-voltage electrolyte and a lithium ion battery using the electrolyte. The invention is realized by the following technical scheme: the high-voltage electrolyte comprises a non-aqueous solvent, lithium salt and an additive, wherein the non-aqueous solvent is a carboxylic ester compound which accounts for 1-40% by mass of the high-voltage electrolyte; the additive is any one or more of lithium bis(oxalate)borate (Li BOB), fluoroethylene carbonate (FEC) and ethylene glycol bis(propionitrile) ether. The high-voltage electrolyte contains carboxylic ester solvents capable of improving an electrode/electrolyte interface, and through optimized combination of the carboxylic ester solvents, Li BOB, FEC, ethylene glycol bis(propionitrile) ether and other various additives, the good cycle performance of a high-voltage battery can be ensured, meanwhile, the high-temperature storage performance of the high-voltage battery can be effectively improved, and gas generation of the battery under high-voltage high-temperature storage condition can be obviously inhibited.

The invention, belonging to the technical field of lithium ion secondary battery, particularly relates to an electrolyte for a lithium ion secondary battery, comprising a non-aqueous solvent, lithium salts and additives, wherein the additives comprise a fluorinated cyclotriphosphazene derivative of formula (I), R1 represents aromatic group or aromatic group containing halogen substituent group, R2 represents alkyl, alkylene or halogen substituted alkyl, alkylene, R3 represents hydrogen, halogen, alkyl or alkyloxy, halogenated alkyl groups or halogenated alkyloxy, and the fluorinated cyclotriphosphazene derivative accounts for 0.1-20 wt% of the total weight of the electrolyte. Compared with the prior art, by using the fire resistance function of fluorinated cyclotriphosphazene derivative, the decomposition of the electrolyte on the anode surface can be effectively prevented, the decomposition and gas generation of the electrolyte are reduced, and the high temperature storage thickness expansion ratio of the battery is greatly reduced. In addition, the invention further discloses a lithium ion secondary battery containing the electrolyte.

The invention relates to the lithium ion battery field, in particular to a high-capacity cathode material and a high energy density lithium ion secondary battery prepared by the cathode material. The cathode material comprises a cathode active material, an adhesive and a conductive agent, wherein the cathode active material is a composite material of a lithium cobalt oxide active material A and a high nickel active material B; the high nickel active material B is pretreated before mixing; and the mass ratio of the high nickel active material B to the lithium cobalt oxide active material A is between 0.82 and 9. The cathode material can not only prepare the batteries with higher capacity and energy density but also solve the problem of high temperature gas production in the batteries.

The invention provides a preparation method of a manganese-based compound positive pole material for a secondary lithium ion battery. The general constitution formula of the positive pole material is Li (LixMn2-x-yMy) O4/Az, wherein x is more than or equal to 0 and less than or equal to 0.5, y is more than or equal to 0 and less than or equal to 2, and z is more than or equal to 0 and less than or equal to 0.5; and M is a doped modified element, and A is an oxide of a coating element or a phthalocyanines large-ring transition metal complex. When the positive pole material is prepared, a lithium source and an M source are added into mixing equipment containing a medium and a dispersing agent to be mixed and dried; then the mixture and a manganese source are added into the mixing equipment containing the medium and the dispersing agent to be mixed and dried; then the new mixture is roasted and then is cooled to a room temperature; and the new mixture and an A source are added into the mixing equipment containing the medium and the dispersing agent to be mixed and dried, are roasted again, are cooled to the room temperature and are mixed and crushed to obtain the manganese-based compound positive pole material. The preparation method disclosed by the invention has the advantages of simple process, low raw material cost and processing cost, simple process route, short period and low energy consumption. The produced manganese-based compound positive pole material has the advantages of high energy density, mass specific capacity, power performance, high-temperature circulating performance and high-temperature storage performance; and the capacity efficiency of the material is high at -40 DEG C.

The invention relates to the technical field of lithium-ion batteries, in particular to electrolyte for a lithium-ion battery made of ternary cathode materials and the lithium-ion battery made of the ternary cathode materials. The electrolyte for the lithium-ion battery comprises a non-aqueous organic solvent, lithium salt and additives, and the additives comprise fluoroethylene carbonate, sulfur-containing organic matters and fluoro-ether. By comparison with the prior art, due to the synergistic effect of the three additives including fluoroethylene carbonate, sulfur-containing organic matters and fluoro-ether, the lithium-ion battery made of the ternary cathode materials has excellent cycle performance and high-temperature storage performance under the high-potential condition of 4.35 V or higher, thus, the lithium-ion battery has a wide application prospect in a ternary battery system.

The invention relates to an electrolyte solution and a lithium ion battery comprising the electrolyte solution. The electrolyte solution comprises a lithium salt, an organic solvent and an additive, wherein the organic solvent comprises a carboxylic ester compound; and the additive comprises a fluoro-ether compound and a dinitrile compound with ether bonds. The electrolyte solution is applied into the lithium ion battery, and particularly after the electrolyte solution is applied into specially-shaped lithium ion batteries, the high-temperature storage performance, high-temperature cycle performance and rate performance of the lithium ion battery can be improved.

The invention relates to the technical field of lithium ion batteries, and particularly discloses a high-temperature high-voltage safety lithium ion battery electrolyte and a lithium ion battery. Thelithium ion battery electrolyte comprises a lithium salt, a non-aqueous organic solvent and an additive, wherein the additive includes an isocyanate additive, a film forming additive and a fluorinatedflame-retardant additive. According to the lithium ion battery electrolyte, by adding the first type of the isocyanate additive and the second type of the film forming additive, a stable SEI film canbe formed on the surface of an electrode material, so that the ion conduction can be facilitated, and the decomposition of the electrolyte can be inhibited; and by adding the third type of the fluorinated flame-retardant additive, F atoms can form a film on an electrode interface, so that the intermolecular force can be reduced, the viscosity of the electrolyte can be reduced, and the conductivity of the electrolyte can be improved. All the components cooperate, so that the battery has good high-temperature storage performance, normal temperature cycling performance and high-temperature cycling performance under a high voltage, and does not have potential safety hazards.

The application discloses an electrolyte additive and application of the electrolyte additive in a lithium ion battery. The electrolyte additive comprises multi-cyano compounds and boracic lithium salts. When the electrolyte additive is applied to the lithium ion battery, the lithium ion battery is enabled to have excellent high temperature cyclic performance and excellent high-temperature storage characteristics.

The invention discloses a non-aqueous electrolyte for a high-voltage rapid-charging type lithium ion battery. The non-aqueous electrolyte comprises a solvent, a commonly-used lithium salt, a positive electrode film-forming additive, lithium bis(polyfluoroalkyloxysulfonyl) imide, a fluoro-ester additive, an organic nitrile additive and a lithium battery electrolyte additive, wherein the ingredients are as follows in parts by weight: 100 parts of solvent, 0.2-10 parts of positive electrode film-forming additive, 0.2-10 parts of lithium bis(polyfluoroalkyloxysulfonyl) imide, 0.2-10 parts of fluoro-ester additive and 0.2-10 parts of organic nitrile additive; the solvent is cyclic carbonate and/or chain carbonate; and the molar concentration of the commonly-used lithium salt in the solvent is 0.8-1.5mol/L. According to the non-aqueous electrolyte provided by the invention, the oxidation resistance and wettability of the electrolyte, the oxidation resistance of the positive electrode SEI film in initial formation and the stability of the negative electrode SEI film can be improved; and the normal temperature rapid-charging circulation, the high-temperature 45-DEG C rapid-charging circulation and the high-temperature storage of the high-voltage electrolyte can be greatly improved.

The invention discloses high voltage electrolyte considering high and low temperature performance and a lithium ion battery using the electrolyte. The high voltage electrolyte comprises a non-aqueous organic solvent, an electrolyte lithium salt, an ether nitrile compound and a low impedance additive, wherein the non-aqueous organic solvent comprises a carbonate solvent and a linear carboxylic acid ester solvent with a wide liquid range; the electrolyte lithium salt is a combination of lithium hexafluorophate and lithium triflurosulfimide according to a molar ratio of 0.01-0.5; and the low impedance additive is a cyclic sulfate compound. The linear carboxylic acid ester solvent for perfecting the electrode/ electrolyte interface is contained in the high voltage electrolyte, by means of the optimized combination of the ether nitrile compound, the lithium triflurosulfimide and the cyclic sulfate compound and other additives, a high voltage battery can be guaranteed to have excellent circulation performance, and meanwhile, the excellent high and low temperature performance of the high voltage battery of storage for 18 h in a full charge state at 85 DEG C and no lithium separation in the full charge state at 0 DEG C is considered.

Provided is a cathode material for a lithium secondary battery, comprising a heat-treated mixture of an oxide powder (a) represented by Formula I and an oxide powder (b) represented by Formula II, wherein a mixing ratio of the oxide powder (a):oxide powder (b) is in a range of 30:70 to 90:10, the oxide powder (a) is monolithic particles having a D50 of more than 10 μm, and the oxide powder (b) is agglomerated particles having a D50 of less than 10 μm, and heat treatment is carried out at a temperature of 400° C. or higher.

LiCoO₂  (I)

Li_zMO₂  (II)

• • wherein 0.95<z<1.1; M=Ni_1-x-yMn_xCo_y, 0<y<0.5, and a ratio of Mn to Ni (x/(1-x-y)) is in a range of 0.4 to 1.1.

The invention provides an electrolyte, and the electrolyte comprises a lithium salt, an organic solvent and an additive A; the additive A comprises one or more kinds of alkylamine compounds, silicon nitrogen compounds and siloxane compounds. In order to improve the electrolyte, the non-aqueous electrolyte has one or more kinds of the alkylamines, compounds with Si-N bonds (the silicon nitrogen compounds) and the siloxane compounds. The non-aqueous electrolyte has extremely low free acid content, is applied to a lithium-ion battery with a high-nickel ternary cathode material and can effectively improve the circulation performance, high-temperature circulation performance and high-temperature storage performance of the lithium-ion battery.

The invention discloses an anode active substance comprising at least one phosphoric acid metal lithium compound and at least one carbon material. The phosphoric acid metal lithium compound has a structural formula of LixMyPO4, wherein M is any transition metal element, x is no smaller than 0 and no larger than 1, and y is no smaller than 0.8 and no larger than 1.2. Also, the invention discloses a production method of the anode active substance and a lithium ion battery employing the anode active substance. According to the invention, with the anode active substance, the diffusion performance of lithium ions can be greatly improved, such that the conductivity of the material can be improved. Therefore, low-resistance improvement can be realized, and negative influences caused by a current carbon cladding method can be avoided. The purity and crystallinity of lithium iron phosphate can be ensured; compaction density and consistency of the material can be improved; and the lithium ion battery employing the anode active substance is provided with good multiplying performance, good low-temperature performance, good high-temperature storing performance, and excellent cyclic performance.

The invention, belonging to the technical field of lithium ion battery, particularly relates to a lithium ion battery electrolyte capable of improving the high temperature storage performance of a lithium ion battery, comprising a non-aqueous solvent, lithium salts dissolved in the non-aqueous solvent, and an additive which is a compound of formula (I), wherein R1, R2, and R3 are selected from hydrogen atom, alkyl containing 1-12 carbon atoms, cycloalkyl containing 3-8 carbon atoms, and aryl containing 6-12 carbon atoms, and n is an integer in the range of 0-7. The compound can effectively passivate the anode and cathode surfaces, prevent oxygenolysis of the electrolyte ingredients on the anode surface and prevent reductive decomposition on the cathode surface, thus gas generation of the battery is reduced, and the high temperature storage performance of the lithium ion battery is raised. In addition, the invention further discloses a lithium ion battery containing the electrolyte.

A high-voltage electrolyte for a lithium ion battery and a lithium ion battery using the electrolyte are disclosed. The high-voltage electrolyte for the lithium ion battery comprises lithium salt, anorganic solvent and an additive. Wherein the organic solvent comprises one or more of a chain carbonate esters, cyclic carbonate esters, carboxylic esters, silicon-substituted organic solvents, wherein the additive comprises a polynitrile compound, and the preparation method of the lithium ion battery comprises injecting the high-voltage electrolyte for the lithium ion battery into a sufficientlydried lithium cobalt oxide/graphite soft-clad battery of 4.45 V, carrying out the steps of shelving at 45 DEG C, high-temperature clamping formation and secondary sealing. The high-voltage electrolytefor lithium ion battery of the present invention can effectively inhibit metal dissolution, reduce decomposition gas production of the electrolyte, protect the positive electrode, improve high-temperature cycling performance and high-temperature storage performance of the battery, reduce the increase of impedance, and improve low-temperature performance of the lithium ion battery.

The invention discloses a low temperature type lithium ion battery electrolyte with high temperature property and lithium ion battery. The electrolyte is made by uniformly mixing and confecting electrolytic salt, non-water organic solvent, alkali additive and film-forming additive, the electrolytic salt is mixed lithium salt made by uniformly mixing lithium tetrafluoroborate and lithium bis(oxalate)borate, and the mol ratio of the two is 96-73: 4-27, the concentration of the mixed lithium salt solution formed by the electrolytic salt and the non-water organic solvent is 0.8-1.2mol/L; the alkali additive is heptamethyldisilazane and the mass ratio of the hepatmethyldisilazane and the non-water organic solvent is 0.1-8%; the mass ratio of the film-forming additive and the non-water organic solvent is 0.1-5%; and the lithium ion battery comprises an anode, a cathode, a diaphragm and low temperature type lithium ion battery electrolyte with high temperature property. The invention has reasonable design, simple preparation method steps and convenient implementation, and the prepared electrolyte and lithium ion battery have favourable comprehensive performances.