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 synthes...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.展开更多
文摘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.
