| 摘要 |
PURPOSE:To provide a battery excellent in a charging characteristic with high safety by filling a nonwoven fabric consisting of a polymer which has a specific range value in thickness and the fibrous structure as a separator with a compound having a polymer matrix which can catch and soak a nonaqueous solvent and an ion dissociative Li salt, and retaining an increase of thickness relative to the thickness of nonwoven fabric not more than the predetermined value. CONSTITUTION:A separator 3 made of a nonwoven fabric is disposed between a positive electrode 7 and a negative electrode 2. The nonwoven fabric is made from a polyolefin material such as polyethylene and polypropylene. To reduce electric resistance of a polymer film, thickness of the film is made maximum 200mum, for example, and in a point of mechanical strength, the minimum thickness is required of 20mum, for example. A vacant part of the nonwoven fabric is filled with an electrolyte impregnation type polyelectrolyte, thereby an internal short circuit caused by arborescent Li generated at the time of charging an Li secondary battery is prevented and the electrolyte is secured so that high conductivity is ensured. An increase of thickness relative to the thickness of nonwoven fabric is defined to 200mum or less. |
