Secondary battery, battery pack, vehicle, and stationary power supply
摘要
說明書
Detailed examples of the lithium phosphate solid electrolyte having the NASICON structure include LATP (Li1+xAlxTi2-x(PO4)3), Li1+xAlxGe2-x (PO4)3, and Li1-xAlxZr2-x (PO4)3. In the above formula, x falls within the range of 0<x≤5, x preferably falls within the range of 0<x≤2, x more preferably falls within the range of 0.1≤x≤0.5. As the solid electrolyte, LATP is preferably used. LATP is excellent in waterproofness and hardly causes hydrolysis in the secondary battery.
As the oxide-based solid electrolyte, LIPON (Li2.9PO3.3N0.40 in an amorphous state or LLZ (Li7La3Zr2O12) having a garnet structure may be used. The solid electrolyte may be of one type, or two or more types may be used in mixture.
As the solid electrolyte particles, a sodium containing solid electrolyte may be used. The sodium containing solid electrolyte is excellent in the ionic conductivity of sodium ions. As the sodium containing solid electrolyte, β-alumina, a sodium phosphorus sulfide, a sodium phosphorus oxide, or the like can be used. The sodium ions containing solid electrolyte preferably has a glass-ceramic form.
The second binder is formed of a polymeric material. The second binder can exist in gaps among the solid electrolyte particles. The second binder improves the binding properties of the solid electrolyte particles.
From the viewpoint of increasing the flexibility of the solid electrolyte layer, the ratio of the second binder in the solid electrolyte layer is preferably 1 mass % or more, more preferably 3 mass % or more, and much more preferably 10 mass % or more.
