SEPARATOR FOR NONAQUEOUS ELECTROLYTE SECONDARY BATTERY

• Main Authors: YOSHIMARU HIROE, YASHIKI DAIZABURO, HARA SHUSAKU
• Format: Patent
• Language: English; Japanese
• Published: 20.09.2018
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRICITY; PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSIONOF CHEMICAL INTO ELECTRICAL ENERGY

PROBLEM TO BE SOLVED: To provide a separator for a nonaqueous electrolyte secondary battery excellent in cycle characteristics.SOLUTION: The separator for nonaqueous electrolyte secondary battery includes a polyolefin porous film. A difference between porosity calculated from a continuous image in which void portions and porous film portions are two graded and porosity calculated from a thickness, weight basis and true density is 4 to 20%.SELECTED DRAWING: None 【課題】サイクル特性に優れる非水電解液二次電池用セパレータの提供。【解決手段】ポリオレフィン多孔質フィルムを含み、上記ポリオレフィン多孔質フィルム表面から内部厚み方向に向かって形成される、空隙部分と多孔質フィルム部分とが二階調化された連続像から算出した空隙率と、厚み、重量目付および真密度から算出した空隙率との差が４〜２０％である非水電解液二次電池用セパレータ。【選択図】なし