Sodium Secondary Battery

Patent metadata

Field	Value
Publication number	US-2016049658-A1
Application number	US-201514824500-A
Country	US
Kind code	A1
Filing date	Aug 12, 2015
Priority date	Aug 13, 2014
Publication date	Feb 18, 2016
Grant date	—

Abstract

Provided is a sodium secondary battery including: an anode containing sodium; a cathode containing sulfur; a cathode electrolyte solution being in contact with the cathode and capable of conducting sodium ions into and from a solid electrolyte membrane; and a solid electrolyte separating the anode and the cathode electrolyte solution and having sodium ion conductivity. The sodium secondary battery of the present invention overcomes the problems of thermal management and heat sealing due to a high operating temperature, possessed by the existing sodium-sulfur battery or sodium-nickel chloride battery (so called, a ZEBRA battery), and may achieve high a charge and discharge mechanism characteristic.

First claim

What is claimed is:

1 . A sodium secondary battery comprising: an anode containing sodium; a cathode containing sulfur; a cathode electrolyte solution being in contact with the cathode and capable of conducting sodium ions into and from a solid electrolyte membrane; and a solid electrolyte separating the anode and the cathode electrolyte solution and having sodium ion conductivity.

2 . The sodium secondary battery of claim 1 , wherein the cathode electrolyte solution is a solution of a sodium salt of following Chemical Formula 1 dissolved in an organic solvent:
NaY  [Chemical Formula 1]
wherein Y is one or more selected from the group consisting of ClO 4 , PF 6 , BF 4 , CF 3 SO 3 , AlCl 4 , AlBr 4 , AlI 4 and N(CF 3 SO 2 ) 2 .

3 . The sodium secondary battery of claim 1 , wherein the cathode electrolyte solution is a molten phase of a sodium salt of following Chemical Formula 2:
NaM(X1) n (X2) 4−n   [Chemical Formula 2]
wherein M is an element selected from the group consisting of metals and metalloids having an oxidation number of 3; X1 and X2 are halogen elements different from each other; and n is a real number of 0≦n≦4.

4 . The sodium secondary battery of claim 1 , wherein it generates a cathode reaction of following Reaction Formula 1 during discharge, and a cathode reaction of following Reaction Formula 2 during charge:
x S+2Na + +2 e − →Na 2 S X ( s )  [Reaction Formula 1]
wherein (s) refers to a solid phase; and x is a natural number of 1 to 5,
Na 2 S X ( s )→ x S+2Na + +2 e −   [Reaction Formula 2]

wherein (s) refers to a solid phase; and x is a natural number of 1 to 5.

5 . The sodium secondary battery of claim 4 , wherein the sulfur in the cathode is present in a liquid state at an operating temperature of the sodium secondary battery.

6 . The sodium secondary battery of claim 1 , wherein it has an operating temperature of 100° C. to 200° C.

7 . The sodium secondary battery of claim 1 , wherein the solid electrolyte is sodium superionic conductor.

Assignees

• Sk Innovation Co Ltd
• Ceramatec Inc

Inventors

• Chae Jehyun
• Kim Jeongsoo
• Kim Jongseon
• Bhavaraju Sai

Classifications

• H01M4/582

  Halogenides · CPC title

• H01M10/3909

  Sodium-sulfur cells · CPC title

• H01M4/5825 Primary

  Oxygenated metallic salts or polyanionic structures, e.g. borates, phosphates, silicates, olivines · CPC title

• H01M2300/0048

  Molten electrolytes used at high temperature · CPC title

• H01M10/3954

  containing additives or special arrangement in the sulfur compartment · CPC title