11 results about "Lithium iron phosphate" patented technology

The invention relates to a surface coating modified lithium ion battery cathode material and a preparation method thereof. The surface coating modified lithium ion battery cathode material has a general chemical formula of LiNi<1-a-b>CoaAlbO2/M, wherein a is more than 0.1 and less than 0.3, b is more than 0.01 and less than 0.2, and M refers to a coating layer. The material is coated by adopting a dry method; the coating layer refers to one or a mixture of two of lithium iron phosphate and lithium ferric manganese phosphate; and the mass ratio of the coating layer to LiNi<1-a-b>CoaAlbO2 is (0.01-0.2):1. The surface coating modified lithium ion battery cathode material and the preparation method thereof disclosed by the invention have the advantages that the stability of the cathode material is improved, and the safety performance of the material is improved; and moreover, in the dry-method coating process, waste liquor is not produced, high-temperature sintering is not needed, and the energy consumption and cost can be reduced.

The invention belongs to the energy material technique field, especially relates to a method for preparing lithium iron phosphate/carbon composite material as an anode material of a lithium ionic cell. The invention synthesizes the lithium iron phosphate by using an iron oxide hydroxide as an iron source, which is not seen at home and abroad. The synthesis process of the compound comprises: mixing the iron oxide hydroxide and a lithium salt, a phosphate salt according to a stoichiometric ratio, adding proper amount of carbon sources and liquid ball milling medium and ball milling the mixture, reacting the dried mixture at a certain temperature, finally getting the lithium iron phosphate/carbon composite material. The products from the invention have advantages of high purity, good crystallization, high capacity and good circulation performance under a high/low rate based on the electrochemistry property testing.

The invention provides a low-temperature electrolyte for a lithium iron phosphate battery. The low-temperature electrolyte is prepared from the following raw materials: an electrolyte lithium salt, an organic solvent and a low-temperature additive, wherein the low-temperature additive is at least one of triethanolamine, tetraethylammonium tetrafluoroborate, 12-crown (ether)-4, 15-crown (ether)-5 and 18-crown (ether)-6; and the mass of the low-temperature additive is 0.1%-5% of total mass of the electrolyte. By the low-temperature electrolyte, the low-temperature performance of the battery is effectively improved.

The invention relates to a method for preparing the cathode material used in a ferrous phosphate lithium battery by adopting low-valent oxyacid of phosphorus; the technical proposal is as follows: lithium salt, ferrous salt, phosphate, and hypophosphorous acid or hypophosphite are blended according to the mol ratio that Li: Fe: PO4<3->: H3PO2 or AH2PO2 or E(H2PO2)2 is equal to x: y (1-z): k. Carbon-containing compound or carbon powder and wet milling liquid are added, ball milling is carried out for 3-12 hours, and the mixture is dried in atmospheric pressure or vacuum at 48-100 DEG C. The dried powder is prepared into the lithium iron phosphate containing controllable Fe2P by two-stage sintering process or temperature programmed two-stage sintering process. When the molecular formula of hypophosphite, one ingredient of the reaction composite, is AH2PO2 or E(H2PO2)2, A is Li<+>, Na <+>, K<+>, Ag<+> or NH<+>, E is Ca<2+>, Sr<2+>, Ba <2+>, Ga <2+>, Ge<2+>, Sn<2+>, Sc<2+>, Mn<2+>, Fe<2+>, Co<2+>, Ni<2+>, Cu<2+>, Zn<2+> or Mo<2+>. The method of the invention has low cost of raw materials, broad source of raw materials, simple preparation and short time consumed; the prepared materials have even composition, excellent discharge performance and good discharge cycling performance in heavy current.

The invention relates to a large-capacity lithium iron phosphate storage battery which is characterized by comprising a plurality of single batteries which are connected in parallel and combined. Eachsingle battery comprises a positive plate, a negative plate, a partition and electrolyte; single battery pole ears and a current collecting plate or the pole ears are folded in half and fastened withthe current collecting plate by adopting the mode of mechanical connection. The large-capacity lithium iron phosphate storage battery has the characteristics of high working voltage, long cycle life,small self discharge and the like, and has the self typical advantages of large capacity (the rated capacity can reach to more than 100Ah), rapid charge and discharge by using large current (more than 200A), reduction of production cost of the storage battery and the like, and is especially suitable for large-capacity and rapid charge and discharge application fields of AGV vehicles and the like.

The invention relates to the technical field of battery recovery, in particular to a lithium iron phosphate battery crushing device and method. Comprising a crushing box; a hammering unit is rotationally connected to the position, close to a port in one end, of the inner wall of the crushing box, and a returning unit is rotationally connected to the position, close to a port in the other end, of the inner wall of the crushing box; the material returning unit comprises a second transmission rod; the second transmission rod is rotationally connected to the inner wall of the end, away from the hammering unit, of the smashing box, and the central axes of the two coincide. A second turntable is mounted on the second transmission rod; a plurality of sets of rotary table extension rods are distributed on the side wall of the second rotary table in an annular array mode, filter screen installation rods are installed at the other ends of the rotary table extension rods, and the other ends of the filter screen installation rods horizontally extend in the direction of the material hammering unit. Waste lithium iron phosphate battery fragments large in size are rebounded through the inner wall of the filter hopper for secondary smashing, and the smashing quality is improved.

The invention provides a lithium iron phosphate/carbon nanobelt composite material, a preparation method and a lithium ion battery. The preparation method comprises the steps that a carbon source compound, a lithium source compound, an iron source compound, a sodium source compound and a phosphorus source compound are subjected to a hydrothermal synthesis reaction, a precursor is obtained, and the sodium source compound is selected from one or more of sodium chloride, sodium sulfide and sodium fluoride; and calcining the precursor in an inert atmosphere to obtain the lithium iron phosphate/carbon nanobelt composite material. By adopting the preparation method, the conductivity of the lithium iron phosphate can be greatly improved, the ion diffusion path is shortened, the rate capability and the cycle performance of the lithium iron phosphate in the application process are further enhanced, and the application power of the lithium iron phosphate is improved.

The invention discloses a positive electrode slurry, which comprises a solid component and a solvent, and is characterized in that the solid component comprises a positive electrode material, a conductive agent, a binder and a positive electrode additive; wherein the positive electrode material is lithium iron phosphate; the positive electrode additive is boric acid; the conductive agent is conductive carbon black SP; wherein the binder is polyvinylidene fluoride (PVDF); wherein the solvent is N-methyl pyrrolidone. The invention discloses a preparation method for the positive electrode slurry,a positive electrode plate and a lithium iron phosphate battery. Boric acid is used as the positive electrode additive in the components of the positive electrode slurry, so that the high-temperaturecycle and the storage performance of the lithium iron phosphate battery can be improved, and the positive electrode slurry has important production practice significance.