| abstract |
The invention relates to a lithium iron phosphate positive electrode material and a preparation method thereof and a battery. The preparation method comprises the following steps: step 1: mixing iron phosphate, lithium source, carbon source and additives to make powder, and then sintering to obtain lithium iron phosphate crystal seed; step 2: mixing the lithium iron phosphate seed crystal with iron phosphate, lithium source, carbon source and additives to make powder, and then sintering to obtain the lithium iron phosphate positive electrode material. The seeds obtained by the first sintering treatment can promote the growth of lithium iron phosphate crystals in the second sintering treatment, and then form a staggered combination of large and small grains, which reduces the gap between the particles, makes the particles in close contact, and improves the compaction density. At the same time, the lithium iron phosphate crystals formed by the iron phosphate, lithium source and carbon source added in the second sintering process only undergo one sintering process, so it is easier to obtain high capacity, so that the final battery product can obtain high energy density. |