| 摘要 |
PURPOSE:To improve the cycling characteristic and self-discharge characteristic by using metal current collectors having through holes with a specific hole diameter and having the specific porosity and thickness in a secondary battery constituted of positive and negative electrode active materials, current collectors, a separator, and a nonaqueous electrolyte. CONSTITUTION:If metal current collectors 3, 3' made of a foil, net, expanded metal, or punching metal of a metal such as steel, aluminum, titanium, stainless steel, nickel and having through holes with an average hole diameter of 5mm or less and the porosity of 5% or more and a thickness of 500mum or less are used, the deterioration of the electrode performance caused by peeling is improved. The average hole diameter is the value obtained by dividing the arithmetic mean of the maximum diameter of holes existing in 1cm<2> by the arithmetic mean of the minimum diameter, and the porosity is the value obtained by multiplying the sum of cross section areas of holes existing in 1cm<2> by 100%. Thereby, the cycling characteristic and self-discharge characteristic are improved. |
