| 摘要 |
PROBLEM TO BE SOLVED: To maintain excellent cycle characteristics while keeping a large capacity by containing N-metylpyrolidone(NMP) in a positive electrode and/or a negative electrode in a specific ratio. SOLUTION: A positive electrode and/or a negative electrode contains 50-500ppm (based on a weight of the electrode) of NMP. The NMP is a solvent capable of dissolving a binder and excellent by dispersing a positive and a negative electrode active substance. The NMP contained in an appropriate quantity (50-500ppm) in the electrode acts on interfaces between the active substances and the binder, whereby wettability of both the interfaces can be enhanced. With such an advantageous result, it is possible to provide a battery having a large capacity and being excellent in cycle characteristics. If a quantity of the NMP contained in the electrode is less than 50ppm, the advantageous result is so good; and if more than 500ppm, a strength of an electrode coating becomes small or a phenomenon such as a small capacity occurs since the NMP is mixed into an electrolyte in a large quantity. |
