Solid-electrolyte material and battery including the same
A solid-electrolyte material includes Li, Y, O, and X. X is at least two elements selected from the group consisting of F, Cl, Br, and I.
1. A solid-electrolyte material comprising:
Li, Y, O, and X,
wherein X is Cl and Br, and
wherein a peak is present at a diffraction angle 2θ of greater than or equal to 13.6° and less than or equal to 14.6°, a diffraction angle 2θ of greater than or equal to 27.8° and less than or equal to 29.0°, a diffraction angle 2θ of greater than or equal to 32.0° and less than or equal to 33.3°, a diffraction angle 2θ of greater than or equal to 46.3° and less than or equal to 47.8°, and a diffraction angle 2θ of greater than or equal to 57.2° and less than or equal to 59.8° in an X-ray diffraction pattern obtained by an X-ray diffraction measurement using Cu-Kα.
2. The solid-electrolyte material according to claim 1 , further comprising:
at least one element selected from the group consisting of Mg, Ca, Zn, Sr, Ba, Al, Sc, Ga, Bi, La, Zr, Hf, Ta, and Nb.
3. The solid-electrolyte material according to claim 1 , wherein the solid-electrolyte material consists of Li, Y, O, and X.
4. The solid-electrolyte material according to claim 1 , wherein a mole fraction of Cl in X is higher than a mole fraction of Br in X.
5. The solid-electrolyte material according to claim 1 , wherein three expressions below are satisfied:
2.6≤ x≤ 3.4,
2.4≤ y≤ 4.1, and
1.4≤ z≤ 2.4,
where
x represents a molar ratio of Li to Y,
y represents a molar ratio of Cl to Y, and
z represents a molar ratio of Br to Y.
6. The solid-electrolyte material according to claim 5 , wherein
2.86≤ x≤ 3.06,
2.65≤ y≤ 3.75, and
1.57≤ z≤ 2.16 are satisfied.
7. The solid-electrolyte material according to claim 1 , wherein an expression below is satisfied:
0< a≤ 0.67,
where a represents a molar ratio of O to Y.
8. The solid-electrolyte material according to claim 7 ,
wherein 0<a≤0.34 is satisfied.
9. A battery comprising:
a positive electrode;
a negative electrode; and
an electrolyte layer interposed between the positive electrode and the negative electrode,
wherein at least one selected from the group consisting of the positive electrode, the negative electrode, and the electrolyte layer includes the solid-electrolyte material according to claim 1 .
10. The solid-electrolyte material according to claim 7 ,
wherein 0.01≤a≤0.67 is satisfied.