| abstract |
The invention relates to a particular multi-layer microporous membrane having a good balance of important properties, including excellent electrochemical stability and low heat shrinkage, while maintaining high permeability and heat resistance, with good mechanical strength, compression resistance and electrolytic solution absorption. Of particular importance when used as a battery separator, the present multi-layer microporous membrane exhibits excellent heat shrinkage, melt down temperature and thermal mechanical properties, i.e. low maximum shrinkage in the molten state. The multi-layer microporous membrane of the present invention is manufactured by layering, such as for example by coextrusion, one or more microporous membrane first layers and one or more microporous membrane second layers, such as on one or both sides of a first layer. The invention further relates to battery separators comprising the multi-layer microporous membrane and batteries utilizing the battery separators. |