SOLID ELECTROLYTE AND METHOD FOR PRODUCING SAME
A solid electrolyte contains Li, P, S, and halogen. The halogen contains at least Br. The solid electrolyte has a crystalline phase having an argyrodite-type crystal structure. The solid electrolyte has a peak A in a range of 2θ=25.2±1.0° in an X-ray diffraction pattern measured by an X-ray diffractometer (XRD) using Cukα1 as a radiation source. When the peak A is separated into two peaks consisting of a peak A1 and a peak A2 through waveform separation, an intensity of the peak A1 is taken as I A1 , and an intensity of the peak A2 is taken as I A2 , I A2 /I A1 is 0.37 or more. When a half-value width of the peak A1 is taken as W A1 , and a half-value width of the peak A2 is taken as W A2 ,W A2 /W A1 is 3.2 or more.
1 . A solid electrolyte comprising a lithium (Li) element, a phosphorus (P) element, a sulfur (S) element, and a halogen (X) element,
wherein the halogen (X) element contains at least a bromine (Br) element,
the solid electrolyte has a crystalline phase having an argyrodite-type crystal structure,
the solid electrolyte has a peak A in a range of 2θ=25.2±1.0° in an X-ray diffraction pattern measured by an X-ray diffractometer (XRD) using Cukα1 as a radiation source,
when the peak A is separated into two peaks consisting of a peak A1 and a peak A2 through waveform separation, an intensity of the peak A1 is taken as I A1 , and an intensity of the peak A2 is taken as I A2 , a ratio (I A2 /I A1 ) of the I A2 to the I A1 is 0.37 or more, and
when a half-value width of the peak A1 is taken as W A1 , and a half-value width of the peak A2 is taken as W A2 , a ratio (W A2 /W A1 ) of the W A2 to the W A1 is 3.2 or more.
2 . The solid electrolyte as set forth in claim 1 , wherein a molar ratio (Br/X) of the bromine (Br) element to the halogen (X) element is 0.5 or more.
3 . The solid electrolyte as set forth in claim 1 ,
wherein a molar ratio (X/P) of the halogen (X) element to the phosphorus (P) element is from 1.0 to 3.0, and
a molar ratio (S/P) of the sulfur (S) element to the phosphorus (P) element is from 3.0 to 5.0.
4 . The solid electrolyte as set forth in claim 1 , wherein a ratio (I A2 /I A1 ) of the I A2 to the I A1 is 1.40 or less.
5 . The solid electrolyte as set forth in claim 1 , wherein a ratio (W A2 /W A1 ) of the W A2 to the W A1 is 15.0 or less.
6 . An electrode material mixture comprising the solid electrolyte as set forth in claim 1 and an active material.
7 . A solid electrolyte layer comprising the solid electrolyte as set forth in claim 1 .
8 . A battery comprising a positive electrode layer, a negative electrode layer, and a solid electrolyte layer between the positive electrode layer and the negative electrode layer, wherein the battery contains the solid electrolyte as set forth in claim 1 .