US-12626951-B2 - Solid electrolyte material and battery using same

US12626951B2US 12626951 B2US12626951 B2US 12626951B2US-12626951-B2

Abstract

The solid electrolyte material of the present disclosure is made of Li, Ca, Y, Gd, X, and O, where X is at least one selected from the group consisting of F, Cl, Br, and I; and the molar ratio of O to the sum of Y and Gd is greater than O and 0.51 or less.

Inventors

Kazufumi Miyatake
Yusuke Nishio
Takashi Kubo
Tetsuya Asano
Akihiro Sakai

Assignees

PANASONIC INTELLECTUAL PROPERTY MANAGEMENT CO., LTD.

Dates

Publication Date: 20260512
Application Date: 20220917
Priority Date: 20200331

Claims (6)

1 . A solid electrolyte material consisting essentially of Li, Ca, Y, Gd, X, and O, wherein X is at least one selected from the group consisting of F, Cl, Br, and I; and a molar ratio of O to the sum of Y and Gd is greater than 0 and 0.51 or less.
2 . The solid electrolyte material according to claim 1 , wherein X is Cl and Br.
3 . A solid electrolyte material consisting essentially of Li, Ca, Y, Gd, X, O, and at least one selected from the group consisting of Sr, Ba, Al, Sc, Ga, Bi, La, Zr, Hf, Ta, and Nb, wherein X is at least one selected from the group consisting of F, Cl, Br, and I; and a molar ratio of O to the sum of Y and Gd is greater than 0 and 0.51 or less.
4 . The solid electrolyte material according to claim 1 , wherein an X-ray diffraction pattern obtained by X-ray diffraction measurement using Cu-Kα rays includes peaks in diffraction angle 2θ ranges of 14.9° or more and 16.2° or less, 16.2° or more and 17.5° or less, 22.2° or more and 23.6° or less, 30.0° or more and 31.3° or less, 39.2° or more and 40.5° or less, and 46.3° or more and 48.2° or less.
5 . The solid electrolyte material according to claim 1 , wherein following four mathematical expressions are satisfied: 2.4≤ x≤ 3.2; 0.06≤ y≤ 0.08; 1.0≤ z≤ 2.0; and 2.3≤ w≤ 4.7, wherein x represents a molar ratio of Li to the sum of Y and Gd; y represents a molar ratio of Ca to the sum of Y and Gd; z represents a molar ratio of Br to the sum of Y and Gd; and w represents a molar ratio of Cl to the sum of Y and Gd.
6 . A battery comprising: a positive electrode; a negative electrode; and an electrolyte layer disposed 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 contains the solid electrolyte material according to claim 1 .

Description

BACKGROUND 1. Technical Field The present disclosure relates to a solid electrolyte material and a battery using it. 2. Description of the Related Art Japanese Unexamined Patent Application Publication No. 2011-129312 discloses an all solid state battery using a sulfide solid electrolyte. International Publication No. WO 2018/025582 discloses a solid electrolyte material represented by Li6-3zYzX6 (0<z<2 is satisfied, and X is Cl or Br). SUMMARY One non-limiting and exemplary embodiment provides a solid electrolyte material having a high lithium ion conductivity. In one general aspect, the techniques disclosed here feature a solid electrolyte material made of Li, Ca, Y, Gd, X, and O, where X is at least one selected from the group consisting of F, Cl, Br, and I; and the molar ratio of O to the sum of Y and Gd is greater than 0 and 0.51 or less. The present disclosure provides a solid electrolyte material having a high lithium ion conductivity. Additional benefits and advantages of the disclosed embodiments will become apparent from the specification and drawings. The benefits and/or advantages may be individually obtained by the various embodiments and features of the specification and drawings, which need not all be provided in order to obtain one or more of such benefits and/or advantages. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows a cross-sectional view of a battery according to a second embodiment; FIG. 2 is a graph showing X-ray diffraction patterns of solid electrolyte materials of Examples 1 to 5 and Comparative Example 1; FIG. 3 is a schematic view of a compression molding die used for evaluation of the ion conductivity of a solid electrolyte material; FIG. 4 is a graph showing a Cole-Cole chart of the impedance measurement results of the solid electrolyte material of Example 1; and FIG. 5 is a graph showing the initial discharge characteristics of the batteries of Example 1 and Comparative Example 1. DETAILED DESCRIPTIONS Embodiments of the present disclosure will now be described with reference to the drawings. First Embodiment The solid electrolyte material according to a first embodiment is made of Li, Ca, Y, Gd, X, and O. Here, X is at least one selected from the group consisting of F, Cl, Br, and I; and the molar ratio of O to the sum of Y and Gd is greater than 0 and 0.51 or less. The solid electrolyte material according to the first embodiment has a high lithium ion conductivity. Here, the high lithium ion conductivity is, for example, 1×10−5 S/cm or more. That is, the solid electrolyte material according to the first embodiment can have, for example, an ion conductivity of 1×10−5 S/cm or more. The solid electrolyte material according to the first embodiment can be used for obtaining an all solid state battery having excellent charge and discharge characteristics. The all solid state battery may be a primary battery or a secondary battery. The solid electrolyte material according to the first embodiment desirably does not contain sulfur. A solid electrolyte material not containing sulfur does not generate hydrogen sulfide, even if it is exposed to the atmosphere, and is therefore excellent in safety. The sulfide solid electrolyte disclosed in Japanese Unexamined Patent Application Publication No. 2011-129312 may generate hydrogen sulfide when it is exposed to the atmosphere. The solid electrolyte material according to the first embodiment may consist essentially of Li, Ca, Y, Gd, X, and O. The phrase “the solid electrolyte material according to the first embodiment consists essentially of Li, Ca, Y, Gd, X, and O” means that the molar proportion (i.e., molar fraction) of the sum of the amounts of Li, Ca, Y, Gd, X, and O to the sum of the amounts of all elements constituting the solid electrolyte material in the solid electrolyte material according to the first embodiment is 90% or more. As an example, the molar proportion may be 95% or more. The solid electrolyte material according to the first embodiment may consist of Li, Ca, Y, Gd, X, and O only. In order to enhance the ion conductivity of the solid electrolyte material, X may be Cl and Br. In order to enhance the ion conductivity of the solid electrolyte material, the solid electrolyte material according to the first embodiment may further include at least one selected from the group consisting of Sr, Ba, Al, Sc, Ga, Bi, La, Zr, Hf, Ta, and Nb. The transition metal included in the solid electrolyte material according to the present embodiment may be only Y and Gd excluding elements included as inevitable impurities. The X-ray diffraction pattern of the solid electrolyte material according to the first embodiment can be obtained using Cu-Kα rays. In the obtained X-ray diffraction pattern, peaks may be present in diffraction angle 20 ranges of 14.9° or more and 16.2° or less, 16.2° or more and 17.5° or less, 22.2° or more and 23.6° or less, 30.0° or more and 31.3° or less, 39.2° or more and 40.5° or less, and 46.3° or more and 48.2° or l