摘要 |
A polycrystalline cobalt-nickel-manganese ternary positive material is provided. The polycrystalline cobalt-nickel-manganese ternary positive material comprises more than two basic crystalline structures of Liz—CoO2, LizNiO2, LizMnO2, LizCo1-(x+y)NixMnyO2, LizNixMn1-xO2, LizCoxNi1-xO2 and Li2MnO3. Further, a method for preparing the positive material by high-temperature fusion is provided. The positive material has the compacted density of 3.9-4.3 g/cm3, the capacity of 145 mAh/g or more when the discharging rate is 0.5-1C and the capacity retention rate of more than 90% after 300 cycles. The positive material prepared by high-temperature fusion has high volume energy density, excellent electrochemical performance, and improved safety and is manufactured economically. Further, a lithium ion secondary battery comprising the positive material is provided. |