| 摘要 |
PROBLEM TO BE SOLVED: To provide a positive active material (LiNiO2 ) with a stable charging- discharging characteristic more safely at high productivity and provide a non- aqueous secondary battery with an excellent charging-discharging characteristic using the active material by adding an organic acid to nickel nitrate-6 hydrates and a lithium compound and firing the obtained mixture. SOLUTION: Nickel nitrate-6 hydrates and a lithium compound are used as a nickel source and a lithium source, respectively, and an organic acid is added to them and the resultant mixture is fired to give a positive active material (LiNiO2 ). It is preferable that the mixture of nickel nitrate-6 hydrates, the lithium compound, and the organic acid is kneaded or stirred at 60-130 deg.C. The firing is carried out at 700-950 deg.C in air or an oxygen-rich atmosphere where oxygen volume ratio is higher than that in air. Further, it is preferable that pre-firing at 130-400 deg.C is carried out previously to the firing. Moreover, it is preferable that firing of the mixture obtained by pre-firing is carried out after the material is cooled or is cooled and pulverized. |
