| 摘要 |
PURPOSE:To obtain a battery having high energy density and long cycle life by using a mixed sinter of MnO2 and NaOH as a positive active material, a material capable of reducing a sodium ion in charging as a negative active material, and a sodium ion conductive nonaqueous electrolyte as an electrolyte. CONSTITUTION:In a positive electrode 1 using a mixed sinter of MnO2 and NaOH, a sodium ion is inserted into the active material by charging and the sodium ion inserted into the active material is reversibly released by discharging. In a negative electrode 6, a sodium ion is reduced by charging and the sodium is oxidized to a sodium ion and released by discharging, and this reaction is more reversible compared with a lithium system. A battery having better reversibility and larger capacity density compared with that using gamma-MnO2 or beta-NnO2 alone is manufactured. Sodium having lower reactivity with an electrolyte than lithium is used. A secondary battery having high energy density and long cycle life is obtained. |
