Abstract: The present disclosure provides a method for preparing lithium iron phosphate from ferric hydroxyphosphate, including: purifying ferrous sulfate to form a ferrous sulfate solution, adding hydrogen peroxide, phosphoric acid, an ammonium dihydrogen phosphate solution and ammonia water into the ferrous sulfate solution and then reacting to form a mixed slurry, holding the mixed slurry at a temperature for a period of time, and then washing with water and subjecting to press filtration to form ferric hydroxyphosphate precursors with different iron-phosphorus ratios; then flash drying, sintering at a high temperature, and pulverizing to obtain ferric hydroxyphosphate precursors with different iron-phosphorus ratios and different specific surface areas.

Abstract: The present disclosure relates to the field of lithium ion batteries, and discloses a lithium iron phosphate lithium-rich oxide composite, a preparation method therefor and use thereof. The method comprises: (1) mechanically fusing LiFePO4 with a lithium-rich oxide in a protective gas atmosphere, wherein the weight ratio of the LiFePO4 to the lithium-rich oxide is 100:2-15; and (2) sequentially sieving and demagnetizing the obtained mechanically fused material to obtain the lithium iron phosphate lithium-rich oxide composite. In the method provided by the present disclosure, by mechanically fusing a specific amount of lithium-rich oxide with LiFePO4, the lithium iron phosphate lithium-rich oxide composite is obtained, and the electrochemical performance of a LiFePO4 lithium ion battery is improved.

Abstract: The present disclosure relates to the technical field of positive electrode lithium-supplementing additives of the lithium battery, and discloses a carbon-coated lithium-rich oxide composite material and a preparation method thereof. The method comprises the following steps: (1) mixing an iron source or a cobalt source with a lithium source, and sintering to obtain a lithium-rich oxide Li5FeO4 or Li6CoO4; wherein, a molar ratio of the lithium source to the iron source is 5-25:1, and a molar ratio of the lithium source to the cobalt source is 6-30:1; (2) crushing the lithium-rich oxide obtained in the step (1); and (3) mixing the lithium-rich oxide crushed in the step (2) with a carbon source, and sintering to obtain the carbon-coated lithium-rich oxide composite material.

Abstract: The present disclosure belongs to the technical field of lithium battery cathode materials, and discloses a preparation method of multiple carbon-coated high-compaction lithium iron manganese phosphate, comprising the following steps: (1) synthesizing a carbon and vanadium co-doped ferromanganese phosphate precursor through a co-precipitation method, sintering, and removing crystal water to obtain an anhydrous ferromanganese phosphate precursor; (2) adding lithium phosphate, a supplemental phosphorus source, an organic carbon source, a dopant and deionized water, and performing ball milling, wet sanding, spray drying and sintering to obtain an intermediate material; and (3) adding deionized water and the organic carbon source, then performing ball milling, sanding, spray drying, sintering and air jet pulverization to obtain multiple carbon-coated high-compaction lithium iron manganese phosphate.