中国有色金属学报(英文版)
Transactions of Nonferrous Metals Society of China
Vol. 33 No. 10 October 2023 |
(State Key Laboratory of Advanced Special Steel, School of Materials Science and Engineering, Shanghai University, Shanghai 200444, China)
Abstract:Sodium ion (Na+)-doped Li1-xNaxNi1/3Co1/3Mn1/3O2 (NCM-Na) cathode materials with enhanced stability were synthesized using a co-precipitation method. The results demonstrate the feasibility of extracting nickel from low nickel matte as a nickel source for synthetic raw materials. Subsequently, the optimal content of Na+ is introduced in advance to occupy partially lithium-ion sites in NCM (Ni, Co, Mn) materials synthesized by chemical reagents, which achieves a stable structure with lower Li+/Ni2+ mixing and improved electrochemical performance. When the dopant content of Na+ is 1 wt.% (x=0.01), the capacity retention ratio of the produced NCM-Na cathode increases from 76.84% to 89.21% after 100 cycles (at 1C). In particular, a specific capacity of 110 mA·h·g-1 is maintained after 200 cycles (at 5C). These results demonstrate that coupling materialization metallurgy and heteroatomic doping are promising strategies for the development of low-cost and high-performance LiNi1/3Co1/3Mn1/3O2 cathodes for advanced lithium-ion batteries.
Key words: lithium-ion batteries; LiNi1/3Co1/3Mn1/3O2 cathode; Na+-doping; diffusion kinetics; low nickel matte