61results about How to "Improve overcharge performance" patented technology

The invention discloses a fast ion conductor modified lithium ion battery anode material lithium cobalt oxide comprising lithium cobalt oxide and a lithium fast ion conductor layer coating the outer surface of the lithium cobalt oxide. The lithium fast ion conductor layer comprises the components of Li1+x+yAxB2-xSiyP3-yO12-eN, wherein A is one or more than one of Al, Sc, La, Cr, Fe, Tl, Eu and In, B is one or more than one of Ti, Zr and Hf, N is one or more than one of Li2O, MgO and Y2O3, and x, y and e are all not less than 0 and not more than 2. The preparation method of the fast ion conductor modified lithium ion battery anode material lithium cobalt oxide comprises the following steps of: evenly mixing A, B an N sources, lithium salt, a silicon source, a phosphorus source and a lithium ion battery anode material to be modified, carrying out the processes of drying, roasting, crushing, screening and the like to prepare the lithium ion battery anode material coated with a phosphate system on the surface. The modified anode material lithium cobalt oxide not only can work under a higher voltage and greatly improve the battery capacity, but also greatly improves the cycle performance, the multiplying power performance, the overcharging performance and the safety performance thereof.

The invention provides a formation method used for a lithium ion secondary battery. The method comprises the following steps that: electrolyte is injected into the lithium ion secondary battery and then aged; subsequently, the lithium ion secondary battery is charged; the charging method comprises a first charging process and a second charging process; after the first charging process is completed, the electrolyte is injected into the lithium ion secondary battery again; the injected electrolyte before the first charging process and the electrolyte which is injected into the lithium ion secondary battery after the first charging process respectively and independently are mixed solution which contains the electrolyte lithium salt and the chain-shaped acid ester; wherein, the electrolyte injected into the lithium ion secondary battery before the first charging process also contains film-forming additive; the electrolyte which is injected into the lithium ion secondary battery again after the first charging process also contains overcharging additive. The formation method of the lithium ion secondary battery of the invention can effectively improve the comprehensive electrochemical performance of the battery.

The invention discloses an aqueous electrolyte solution of a secondary lithium ion battery with ferric phosphate considering as the positive material and with both the high temperature performance and the low temperature performance. The aqueous electrolyte solution comprises LiPF6 lithium salt, an organic solvent and a film-forming additive, and is characterized in that the electrolyte solution further comprises high temperature additive; the organic solvent is composed of one or a plurality of carbonic esters and one or more carboxylic esters with low melting point and high boiling point. The carboxylic esters with low melting point and high boiling point are selected from one or a combination of methyl butyrate, ethyl butyrate, propyl butyrate and butyl acetate. The high temperature additive is 1, 3- propane sultone and 1, 4- butane sultone. The electrolyte solution is used for maintaining both the circulation performance in a high temperature state and the low temperature laying performance of the secondary lithium ion battery with the ferric phosphate lithium as the positive material.

Provided are a positive electrode material for lithium ion batteries and a process for preparing the same. The positive electrode material for lithium ion batteries comprises a composite positive electrode material consists of LiCoO2 and an auxiliary positive electrode material, the general formula of the auxiliary positive electrode material is LiCo1−x−yNixMnyO2, wherein 0<x<0.9, 0<y<0.9, 0<x+y<0.9, and the LiCoO2 is a modified LiCoO2 coated with an Al2O3 film. The overcharge performance of the batteries can be significantly increased and the use amount of the overcharge additive can be reduced by using the positive electrode material so as to its improve the cycle performance of the batteries and improve the anti-overcharge safety in the special applications and the charging conditions.

The invention discloses a coating for a lithium-battery diaphragm, the diaphragm and a preparation method for the diaphragm. The coating for the lithium-battery diaphragm comprises powder of a lithium titanate compound and an adhesive, wherein the lithium titanate compound is one or more selected from a group consisting of Li<4+x>Ti<5>O<12> and Li<1+x>Ti<2>(PO<4>)<3>, wherein x is no less than 0 and no more than 3. The coating for the lithium-battery diaphragm can improve the puncture strength of the diaphragm and supplement lithium to an electrical core, and the preparation method is simple in process and easy to operate. Compared with conventional coatings, Li<4+x>Ti<5>O<12> provided by the invention is a substance with certain electron conductivity and high ion conductivity, so the ion conductivity of an electrolyte can be improved and the electrical properties of the electrical core are enhanced; under the condition of over-charging, Li<4+x>Ti<5>O<12> can store a part of Li ions, effectively prevent precipitation of surplus lithium and improve the over-charging performance of the electrical core; and compared with conventional lithium supplementing technology, the coating is easier to operate and enables security to be substantially improved.

The preparation process of artificial graphite charcoal as negative pole material includes the following steps: 1. adding artificial graphite powder and asphalt in the weight ratio of 1.5-19 to 1 while stirring, stirring for further 0.5-3 hr, and adding reaction assistant in 4-20 wt% of graphite powder and asphalt within 10-50 min; 2. heating to 500-600 deg.c in 4-10 hr and pumping out the light component in the first 1-2 hr; 3. maintaining at 500-600 deg.c for 3-8 hr while pumping out the heavy components and reaction assistant; 4. cooling to room temperature and 5. graphitizing. The present invention has environment friendship and high yield, and the prepared artificial graphite charcoal as negative pole material has the advantages of common artificial graphite, the density near that of natural graphite and lowered specific surface area.

The invention provides a high-safety high-energy long-cycle lithium iron phosphate type 18650 lithium battery and a preparation method thereof. The cathode active material of the battery is carbon doped coated lithium iron phosphate with a small particle size and uniform particle size distribution, with the specific capacity being not less than 155 mAh / g and the compaction density being 2.0 - 2.8g / cm<3>; the anode active material is graphite with the specific capacity being 350 - 375 mAh / g and the compaction density being not less than 1. 7 g / cm<3>; a membrane is a PE base membrane coated with a nanometer Al2O3 ceramic membrane. The method comprises the steps of homogenizing, coating, rolling, cutting, winding, shelling, liquid injection, cleaning, oiling, forming and mixing. The batteryenergy density of the invention is as high as 390Wh / L, the discharge capacity of the monomer cell 0.2 C is not less than 2000 mAh, the cycle performance is excellent, the capacity retention rate of the cell 0.5 C / 0. 5C100% DOD after 1000 cycles is above 80%, the thermal stability is good, and the overcharge performance is good.

The invention provides a positive active material of a Li-ion battery. The positive active material contains an oxide IA with a formula of LiNi1-x-yCoxMyO2, wherein x and y are mole fractions; the summation of x and y is not less than 0 and less than 1; and M is selected from one or more of a group including Al, B, Mn, Fe, Ti, Mg, Cr, Ga, Cu, Zn, Y, Sr and Nb. The positive active material also contains an oxide IB having a formula of Li(NiMn)(1-a-b) / 2CoaXbO2, wherein a and b are mole fractions; the summation of a and b is not less than 0 and less than 1; and X is selected from one or more of a group including Al, B, Fe, Ti, Mg, Cr, Ga, Cu, Zn, Y, Sr and Nb. In addition, the invention also provides the positive active material preparation method. The positive active material has the advantages of excellent thermal stability, rate discharge performance, circle performance and overcharge performance.

A charge storage device (1) includes a sealed prismatic housing (2). Two opposed folded rectangular aluminium electrodes (3, 4) are disposed within housing (2) and connected to respective metal terminals (5, 6) for allowing external electrical connection to the electrodes. A porous, electronically insulating separator material, e.g. Solupor™, sheet separator (7) is disposed intermediate electrodes (3, 4) for maintaining those electrodes in a fixed spaced apart configuration. An electrolyte (not shown) is also disposed intermediate the electrodes. Collecting means in the form of a scavenging agent is grafted to separator (7) for sequestering one or more predetermined contaminants from the housing.

The invention belongs to the field of lithium-ion batteries, and particularly relates to a non-aqueous electrolyte solution and a lithium-ion battery using the same. The non-aqueous electrolyte solution comprises a non-aqueous organic solvent, lithium salts and additives; the non-aqueous organic solvent comprises at least one cyclic lactone compound; the additives comprise at least a negative electrode film-forming additive and at least a positive electrode passivation protective agent; and the positive electrode passivation positive agent is selected from at least one of 3,4-ethylenedioxythiophene, a cyclic anhydride phosphonate compound and a nitrile compound. The reduction potential of the negative electrode film-forming additive in the non-aqueous electrolyte solution is higher than that of the cyclic lactone compound, and a steady negative electrode passivation film can be formed; the positive electrode passivation protective agent can suppress oxygenolysis of the cyclic lactone compound at the positive electrode, so that the overcharging performance of the lithium-ion battery not only can be improved, but the cycle performance of the battery is also not affected.

The invention relates to a composite conductive agent, a lithium ion battery positive electrode and a lithium ion battery. The composite conductive agent consists of conductive carbon black, conductive graphite and a carbon nano tube according to the weight ratio of (1.5-2.0):(1.4-2.0):(0.7-1.0). According to the composite conductive agent provided by the invention, the conductive carbon black isrelatively small in particle size and belongs to a dot-shaped conductive agent; the carbon nano tube is provided with a linear structure and belongs to a linear conductive agent; the conductive graphite is of a laminated structure and belongs to a planar conductive agent; through the organic combination of three different dimensions of conductive agents in a ternary battery, the advantages of allthe conductive agents can be comprehensively utilized, a synergetic coupling effect is fully played, the direct-current internal resistance is reduced in multiple aspects of improving the compaction,promoting the dispersion, constructing a conductive network, improving the ionic and electronic conductivity and the like, and finally, the purpose of optimizing the overcharge performance of the ternary battery is realized.

The invention discloses an improved anode material of a lithium ion battery, which is composed of lithium cobaltate and a solid electrolyte layer coating the outer surface of lithium cobaltate, wherein the solid electrolyte layer consists of Li(1+x)AxB(2-x)Si3O12-eN; 0<=x<=2; the A is one of Al, Sc, La, Cr, V, Fe, Tl, Eu and In; the B is Ti, Zr or Hf; and the N is one or combination of more of Li2O, MgO and Y2O3. The invention also discloses a preparation method of the anode material. The material can realize work at higher voltage and remarkably increase the battery capacity, and also greatly improves the cycle performance, the rate capability, the over-charge performance and the safety performance.

The invention provides an anti-overcharging electrolyte based on a ternary lithium ion battery and a lithium ion battery. The anti-overcharging electrolyte is characterized by comprising lithium salt, an organic solvent, an overcharging additive, a salt additive and a function additive, wherein the overcharging additive comprises one or more than two aromatic derivatives A and / or B, the mass of each of the derivatives A and B accounts for 0.01%-5% of the mass of the electrolyte. According to the anti-overcharging electrolyte provided by the invention, Ni-Co-Mn ternary material can be obviously improved, the overcharging performance of the battery particularly under the condition of increase of nickel content can be improved; furthermore, on the premise of improving overcharging, the usage amount of the additives is reduced to the greatest extent (less than 5%), the charging and discharging capacity cannot be affected obviously, a battery DCR is unchanged basically, and the cycling life is not shortened obviously.

The invention relates to a lithium supplementing method for a lithium iron phosphate lithium ion battery and the lithium iron phosphate lithium ion battery. The lithium ion battery is formed by assembling a positive plate, a negative plate and a diaphragm, a positive material in the positive plate comprises lithium iron phosphate, a conductive agent, a binder and a lithium supplement additive lithium-rich manganese material xLi2MnO3.(1-x) LiTMO2, x is more than 0 and less than 1, TM is one or more of Ni, Co and Mn, and x is more than 0 and less than 1. A negative electrode material in the negative electrode plate comprises a negative electrode active substance, a conductive agent and a lithium-containing binder; and after the positive electrode plate, the negative electrode plate and the diaphragm are assembled into the battery, the battery is pre-charged and formed in a mode of combining step current and constant-voltage current limiting. According to the lithium supplementing method for the lithium iron phosphate lithium ion battery, lithium can be supplemented to the positive electrode and the negative electrode at the same time, the overall first effect and cycle performance of the battery are improved, no non-conductive residues are generated, no extra special equipment is needed, operation is easy, and the cost is low.

The invention discloses a lithium ion battery and electrolyte thereof. The electrolyte comprises a nonaqueous organic solvent, lithium salts, and additives. The nonaqueous organic solvent contains a methyl ester compound (A). The additives comprise a polycyano compound (B) and a hydrocarbyl lithium phosphite compound (C). Compared with the prior art, through the cooperation among the methyl estercompound (A), the polycyano compound (B), and the hydrocarbyl lithium phosphite compound (C) in the electrolyte, the reactions between the solvent and the lithium are prevented, the overcharge performance and high temperature storage performance of the lithium ion battery are obviously improved, and the safety performance of the lithium ion battery is enhanced.

The invention relates to the field of energy storage materials, particularly to an electrolyte solution and a battery. The electrolyte solution of the invention comprises an organic solvent, an electrolyte and an additive, wherein the additive comprises a fluorophosphate compound and lithium sulfide. According to the electrolyte solution provided by the invention, the electrolyte solution comprises both fluorophosphate and lithium sulfide, so the high-voltage cycle performance, storage performance and overcharge performance of the battery can be remarkably improved.

The invention relates to the field of lithium ion batteries, and discloses an additive used for a lithium ion battery electrolyte and the electrolyte and the lithium ion battery, wherein the additivecontains an additive a, an additive b and an additive c; the structural formula of the additive a is as shown in structural formula 1; the additive b is at least one of lithium difluorophosphate, lithium difluoroborate and lithium difluorosulfonimide; the additive c is at least one of vinylene carbonate, 1, 3-propane sultone, fluoroethylene carbonate, vinyl vinyl carbonate, glycol sulfite, vinylidene sulfate, propylene sulfite, dimethyl sulfate and trimethylene Sulfite. The additive is mixed by several mixtures, and is applied to the lithium ion battery electrolyte; the electrolyte has excellent overcharge performance, and is excellent in flame retardant property; furthermore, the lithium ion battery using the electrolyte has very small internal resistance and K value, and has relatively good normal temperature circulating performance and high temperature storage property.

A lithium cell of portable electronic apparatus, includes shell, positive active material in the shell, negative active material and electrodes formed by the material, membrane and electrolyte between electrode, whose characteristic is that the positive active material is compound material mixed by lithium-cobalt oxide (LiCoO2) and lithium-manganese oxide (LiMnO4).It can be used as electric powder source in mobile phone, digital photographer digital camera MP3 and another portable electronic apparatus, has low cost and excellent property, solves the problem that lithium cell is prone to expand and increases overcharge property of battery.

The invention belongs to the field of lithium battery materials and particularly discloses a composite thermistor material. The composite thermistor material is characterized by comprising a fullerenematerial, a PTC material and an assistant. The invention further provides a thermistor compounded with the composite thermistor material, a thermosensitive lug assembled by the thermistor and a lithium-ion battery assembled by the thermosensitive lug. The inventor accidentally finds that the performance can be collaboratively improved through combined use of the fullerene material and the PTC material through a large number of studies. The lithium-ion battery with excellent overcharge resistance can be obtained through applying the lug provided by the invention into assembly of the lithium-ion battery; and especially a PTC thermistor containing the fullerene material is added between lugs of a soft package battery, so that the internal resistance of the whole battery can be reduced through reducing the room-temperature internal resistance rate of a PTC, and the overcharge performance of the soft package lithium-ion battery can be effectively improved to enhance the safety performanceof the battery.

The invention discloses a cathode composite active substance for lithium-ion batteries and a preparation method of coating slurry thereof. The cathode composite active substance is composed of LiFePO4 and a Li-Mn oxide in a weight ratio of (92-97): (3-8). According to the cathode composite active substance disclosed by the invention, by using the voltage difference of the two kinds of materials relative to graphite and respective advantages of the materials, the overcharge capacity and low-temperature discharge capacity of a monomer battery are improved, therefore, the cycle life of a battery pack is prolonged, and the energy utilization rate and low-temperature discharge rate of the battery pack can be effectively increased. According to the preparation method of coating slurry provided by the invention, by taking deionized water as a solvent, both finished products can be reduced and the pollution can be reduced, and due to the preparation method, various materials can be uniformly mixed and completely dispersed effectively.

The invention discloses a lithium-ion battery and an electrolyte thereof. The electrolyte comprises a non-aqueous organic solvent, lithium salt and additives, wherein the non-aqueous organic solvent contains a methyl ester compound A; the additives comprise an additive B--a silicon oxysulfide compound and an additive C which is at least one selected from the group consisting of an ether bond containing lithium disulfonate compound and an ether bond containing lithium disulfate compound; and the silicon oxysulfide compound is at least one selected from the group consisting of compounds as shownin a formula (I) which is described in the specification. Compared with the prior art, the lithium-ion battery and an electrolyte thereof provided by the invention have the following advantages: through synergistic effect of the methyl ester compound A, the additive B and the additive C, overcharge resistance and cycle performance of the lithium-ion battery can be improved, and the safety performance of the battery is improved.

A charge storage device (1) includes a sealed prismatic housing (2). Two opposed folded rectangular aluminium electrodes (3, 4) are disposed within housing (2) and connected to the electrodes. A porous, electronically insulating separator material, e.g. Solupor™, sheet separator (7) is disposed intermediate electrodes (3, 4) for maintaining those electrodes in a fixed spaced apart configuration. An electrolyte (not shown) is also disposed intermediate the electrodes. Collecting means in the form of a scavenging agent is grafted to separator (7) for sequestering one or more predetermined contaminants from the housing.

The invention discloses a lithium ion battery and a preparation method thereof. The lithium ion battery comprises a current collector, an active substance layer, a ceramic layer and a polymer microsphere particle layer. The active substance layer is formed on at least part of the surface of the current collector, the ceramic layer is formed on at least part of the surface of the active substance layer away from the current collector, and the polymer microsphere particle layer is formed on at least part of the surface, away from the active substance layer, of the ceramic layer. According to thelithium ion battery, the pole piece coated with the ceramic layer and the polymer microsphere particle layer is adopted, so that the wettability of electrolyte to the pole piece can be effectively improved, thermal shutdown is realized at high temperature, and the overcharge, needling and heating safety performance of the battery is effectively improved.

The invention provides an electrode sheet and an electrochemical energy storage device. The electrode sheet comprises a current collector and an active material layer. The electrode sheet further comprises a conductive coating. The conductive coating is arranged between the current collector and the active material layer and comprises a conductive polymer and a carbon-based conductive material. The conductive polymer is selected from complexes of polythiophene and polyanion. The electrode sheet provided by the invention can enable the electrochemical energy storage device to have relatively low initial internal resistance and have good kinetic properties; meanwhile, when the electrochemical energy storage device is abused, the safety performance of the electrochemical energy storage deviceis improved, and the thermal shock resistance and overcharge performance of the electrochemical energy storage device are improved; meanwhile, the electrochemical energy storage device further has good cycle performance and high-temperature storage performance.

The invention relates to a storage battery, especially relates to a battery with improved over charge performance of lithium ion battery. An anode comprises the following components by weight: 18-56% of ternary material, 37-72% of lithium manganate, 3-4% of polyvinylidene fluoride and 4-6% of conductive agent; a cathode comprises the following components by weight: 94-96% of graphite, 25-3% of aqueous binder, 0.5-1% of carboxymethylcellulose sodium and 1-2% of butadiene styrene rubber binder, in the prerequisite that the routine lithium ion battery has the cycle life, the safety performance and the low temperature performance, the battery 1C is charged to 10V at constant current and constant voltage, and when the cut-off current is 0.01C, the temperature rises to 101 DEG C, and if the duration of charging is more than or equal to 3 hours, and the battery does not generate smoke, leak, fire and explode, thereby effectively improving the over charge performance of the battery and safety performance of the ternary material lithium battery.

The invention provides a negative plate with a sandwich structure and a lithium ion battery comprising the negative plate. When a conventional lithium ion battery is subjected to a needling test, an internal short circuit occurs, a large amount of heat is generated in a short time due to relatively large current density of the internal short circuit, thermal shrinkage of a diaphragm is caused, andfinally thermal runaway of the battery is caused. A lithium titanate layer is contained in the negative plate, lithium can be rapidly removed at the moment of internal short circuit to form an air-state insulator, the resistance of the negative plate is sharply increased in the process, the short-circuit current can be reduced, and then the needling safety of the lithium ion battery can be improved. A silicon material layer is contained in the negative plate, lithium dendrites can be consumed through reaction when the silicon material layer makes contact with the lithium dendrites, the situation that the negative plate seriously separates out lithium to form a large number of lithium dendrites in the overcharge process of the battery cell is avoided, and internal short circuit caused by the fact that the lithium dendrites pierce a diaphragm is further avoided.

The invention relates to lithium battery electrolyte which is prepared from lithium salt, an organic solvent and additives. The additives include the additive S accounting for 0.1-10% of the total mass of the lithium battery electrolyte, the additive S is one or more of elements in the following structural formula (shown in the description), wherein R1-R5 are independently selected from H, halogen, nitryl, amino, cyano, alkyl substituted by the halogen or not substituted by the halogen, alkoxy substituted by the halogen or not substituted by the halogen, alkenyl substituted by the halogen or not substituted by the halogen, R6 represents alkyl, the halogen substituted by the halogen is F, Cl and Br, and the substitution performed by the halogen is partial or complete. The overcharge, charge and discharge performance of a lithium battery are all improved, side reaction is reduced, expansion of the battery under high temperature is decreased, and the cycle life of the battery under normal temperature, high temperature and low temperature is prolonged.

The invention provides an overcharge-resistant pole piece, a method for preparing the same, and a lithium ion battery, and belongs to the technical field of lithium ion batteries. The overcharge-resistant pole piece includes an overcharge-resistant coating and a pole piece layer. The overcharge-resistant coating is disposed on both surfaces of the pole piece layer, and includes an overcharge-resistant material. The overcharge-resistant material includes one or more of the group consisting of silicon, oxide of silicon, oxide of tin, titanium dioxide, tungsten oxide, iron oxide, molybdenum oxide, cobalt oxide, copper oxide, and nickel oxide, and lithium titanate. The overcharge-resistant material can consume the lithium dendrites formed during an overcharge process to prevent the lithium dendrites from piercing a diaphragm and further from causing an internal short circuit. Further, the consumption of the lithium dendrite can reduce its side reaction with an electrolyte, thereby improving the battery's overcharge performance. The diaphragm shrinks under a heat abuse condition, and the overcharge-resistant coating on the positive and negative pole pieces can isolate the positive and negative electrodes, avoid internal short circuits, and improve the safety of a battery cell.

The invention discloses an electrolytical lithium salt and a lithium ion battery electrolyte containing the electrolytical lithium salt. The chemical formula of the electrolytical lithium salt is LiC11H6BO3F2; and the structural formula is shown in the specification. The lithium ion battery electrolyte contains a nonaqueous organic solvent, an additive and the electrolytical lithium salt, wherein the content of the electrolytical lithium salt accounts for 0.01-15% of the total weight of the electrolyte. According to the invention, through the introduction of the electrolytical lithium salt LiC11H6BO3F2, the comprehensive performance of the lithium ion battery electrolyte is improved; due to the lithium ion battery electrolyte, the charge and discharge capacities, coulombic efficiency and long cycle performance of a battery can be significantly improved; and the internal resistance of the battery is reduced to some extent. In addition, the lithium ion battery electrolyte containing the electrolytical lithium salt has a good overcharge performance.