Secondary battery, battery pack, vehicle, and stationary power supply
摘要
說明書
As the negative electrode active material, more specifically, a titanium oxide or a titanium-containing oxide can be used. As the titanium-containing oxide, a lithium titanium composite oxide, a niobium titanium composite oxide, a sodium niobium titanium composite oxide and the like can be used. One type or two or more types of the titanium oxide and the titanium-containing oxide can be included in the negative electrode active material.
The titanium oxide includes, for example, a titanium oxide having a monoclinic structure, a titanium oxide having a rutile structure, and a titanium oxide having an anatase structure. For titanium oxides of these crystal structures, the composition before charge can be expressed as TiO2, and the composition after charge can be expressed as LixTiO2 (0≤x≤1). In addition, the structure of titanium oxide having a monoclinic structure before charge can be expressed as TiO2(B).
The lithium titanium composite oxide includes, for example, a lithium titanium composite oxide having a spinel structure (for example, the general formula is Li4+xTi5O12 (?1≤x≤3)), a lithium titanium composite oxide having a ramsdellite structure (for example, Li2+xTi3O7 (?1≤x≤3)), Li1+xTi2O4 (0≤x≤1), Li1.1+xTi1.8O4 (0≤x≤1), Li1.07+xTi1.86O4 (0≤x≤1), and LixTiO2 (0<x≤1), and the like. The lithium titanium composite oxide may be a lithium titanium composite oxide in which a dopant is introduced.
