High conductivity NASICON electrolyte for room temperature solid-state sodium ion batteries

Patent metadata

Field	Value
Publication number	US-10276892-B2
Application number	US-201314430453-A
Country	US
Kind code	B2
Filing date	Sep 25, 2013
Priority date	Sep 25, 2012
Publication date	Apr 30, 2019
Grant date	Apr 30, 2019

Abstract

Solid electrolytes compositions, methods of making the solid electrolytes, and methods of using the solid electrolytes in batteries and other electrochemical technologies are disclosed. The method of producing a solid electrolyte comprises (a) ball milling Na2CO3, SiO2, NH4H2PO4, a zirconium source, and a dopant to produce a ball milled powder; (b) calcining the ball milled powder to produce a calcined powder; and (c) sintering the calcined powder to produce a solid electrolyte. The zirconium source for the solid electrolyte may be ZrO2. The dopant for the solid electrolyte may be AI2O3, Fe2O3, Sb2O3, Yb2O3, or Dy2O3.

First claim

What is claimed is:

1. A solid electrolyte of formula (I):
Na 3+x M x Zr 2-x Si 2 PO 12   (I)

wherein
M is a metal ion selected from the group consisting of Sb 3+ , Dy 3+ , and Er 3+ , and
x is between 0.01 and 2.

2. The solid electrolyte of claim 1 , wherein x is between 0.8 and 1.2.

3. The solid electrolyte of claim 1 , wherein x is between 0.9 and 1.1.

4. The solid electrolyte of claim 1 , wherein x is 1.

5. The solid electrolyte of claim 1 , wherein the solid electrolyte of formula (I) is selected from the group consisting of:
Na 4 ZrSbSi 2 PO 12 ; and
Na 4 ZrDySi 2 PO 12 .

6. The solid electrolyte of claim 1 , wherein the ionic conductivity at 25° C. is between 0.1 and 0.001 S/cm.

7. A method of producing the solid electrolyte of claim 1 comprising:
(a) ball milling Na 2 CO 3 , SiO 2 , NH 4 H 2 PO 4 , a zirconium source, and a dopant to produce a ball milled powder;
(b) calcining the ball milled powder to produce a calcined powder; and
(c) sintering the calcined powder to produce the solid electrolyte of claim 1 .

8. The method of claim 7 , wherein the zirconium source is ZrO 2 .

9. The method of claim 7 , wherein the dopant is selected from the group consisting of Sb 2 O 3 and Dy 2 O 3 .

10. The method of claim 7 , wherein the ball milled powder is calcined at a temperature between 800° C. and 1200° C.

11. The method of claim 7 , wherein the ball milled powder is calcined at a temperature between 900° C. and 1100° C.

12. The method of claim 7 , wherein the calcined powder is sintered at a temperature between 900° C. and 1400° C.

13. The method of claim 7 , wherein the calcined powder is sintered at a temperature between 1000° C. and 1300° C.

Assignees

• Univ Maryland

Inventors

• Wachsman Eric D
• Hitz Gregory Thomas
• Lee Kang Taek

Classifications

• H01M2008/1293

  Fuel cells with solid oxide electrolytes · CPC title

• H01M10/39

  working at high temperature · CPC title

• H01M10/05

  Accumulators with non-aqueous electrolyte (H01M10/39 takes precedence) · CPC title

• C01B25/45

  containing plural metal, or metal and ammonium · CPC title

• H01M2300/0071

  Oxides · CPC title