Sodium ion secondary battery

文件类型：PDF文档
文件大小：504K
PROBLEM TO BE SOLVED : To provide a sodium ion secondary battery capable of achieving high energy density at a low cost. SOLUTION : The present invention relates to a sodium ion secondary battery including a positive electrode, a negative electrode and an electrolyte containing sodium ions. Specifically, the positive electrode is an electrode having an active material including a sodium-containing composite metal oxide represented by Na2MO3 (where, M represents at least one or more transition metal elements). Thus, high energy density can be secured at a low cost by achieving a two-electron positive electrode reaction in which two equivalents of sodium ions are released and inserted, without using expensive rare metals such as lithium. COPYRIGHT : (C)2015, JPO&INPIT