摘要
The commercialized lithium secondary cells need the electrode materials with high speeific capacity, lower pollution and lower price. Certain industrial materials ( NiSO_4, CoSO_4 , LiOH·H_2O)were used to synthesize Ni_(0.8)Co_(0.2)(OH)_2 of a stratified structure, when various synthesis conditions such as pH, reaction temperature et al. were controlled strictly. After LiOH·H_2O and Ni_(0.8)Co_(0.2) (OH)_2were calcinated in air atmosphere, LiNi_(0.8)Co_(0.2)O_2 positive electrode materials with good layered crystal structure was obtained. Tests showed that the optimal calcination temperature in air atmosphere was about at 720℃ and LiNi_(0.8)Co_(0.2)O_2 synthesized in the above conditions had good electrochemical properties and a low cost. The first specific: discharge capacity of the material was 186 mAh/g, and the specific discharge capacity was 175 mAh/g after 50 cycles at a 0.2C rate, between 3.0～4.2 V with a discharge deterioration ratio of 0.22% each cycle. Tests showed that LiNi_(0.8)Co_(0.2)O_2 positive electrode materials was a promising candidate to replace the commereialized LiCoO_2 for lithium secondary batteries.
The commercialized lithium secondary cells need the electrode materials with high specific capacity,lower pollution and lower price. Certain industrial materials (NiS04, COS04, LiOH·H2O)were used to synthe-size Nio.8 CO0.2 (OH)2of a stratified structure, when various synthesis conditions such as pH, reaction temperature et al. were controlled strictly. After LiOH - H20 and Nio. s Coo. 2 (OH)2were calcinated in air atmosphere,LiNio.8 CO0.202 positive electrode materials with good layered crystal structure was obtained. Tests showed that the optimal calcination temperature in air atmosphere was about at 720 ℃ and LiNio.8 CO0.2 O2 synthesized in the above conditions had good electrochemical properties and a low cost. The first specific discharge capacity of the material was 186 mAh/g, and the specific discharge capacity was 175 mAh/g after 50 cycles at a 0. 2C rate,between 3.0 — 4. 2 V with a discharge deterioration ratio of 0. 22% each cycle. Tests showed that LiNio.8 CO0.2 O2 positive electrode materials was a promising candidate to replace the commercialized LiCoO2 for lithium secondary batteries.
