Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
9760277 | Journal of Power Sources | 2005 | 6 Pages |
Abstract
Lithium ion batteries are widely used in many portable devices; however, their power density is not sufficient for use in electric vehicles. One of the most effective methods to improve the power density is the use of very fine cathode particles. We investigated a new excess lithium method of preparing nano-sized LiCoO2 powders. To begin with, lithium acetate and cobalt acetate are mixed by the molar ratio 9, 13 or 21 to 1, uniformly. The mixture is then calcined at 600 °C for 6 h. Finally, obtained powders are washed with a large amount of water to remove impurity and then dried. Using this method, we obtained nano-sized spherical LiCoO2 particles with a diameter of about 25 nm or needlelike LiCoO2 particles with a diameter of about 5 nm and a length of about 60 nm. The discharge capacity of a Li/5 μm LiCoO2 cell is 51 mAh gâ1, but when the nano-sized LiCoO2 was used, the capacity increased to about 100 mAh gâ1 at the same cycling condition.
Keywords
Related Topics
Physical Sciences and Engineering
Chemistry
Electrochemistry
Authors
Tetsuya Kawamura, Masami Makidera, Shigeto Okada, Kazumichi Koga, Norio Miura, Jun-ichi Yamaki,