Lithium ion capacitor

Patent metadata

Field	Value
Publication number	US-10580589-B2
Application number	US-201715474378-A
Country	US
Kind code	B2
Filing date	Mar 30, 2017
Priority date	May 30, 2016
Publication date	Mar 3, 2020
Grant date	Mar 3, 2020

Abstract

A lithium ion capacitor has an electrolytic solution that contains: 100 parts by volume of a solvent containing 20 to 50 parts by volume of propylene carbonate, 10 to 35 parts by volume of dimethyl carbonate, and 15 to 70 parts by volume of ethyl methyl carbonate; and lithium bis(fluorosulfonyl)imide, as an electrolyte. The lithium ion capacitor can maintain its initial high capacitance and low internal resistance, while also undergoing minimal characteristics changes in a low-temperature environment, even after exposure to a high-temperature, high-voltage environment.

First claim

I claim:

1. A lithium ion capacitor having an electrolytic solution that contains:
a solvent containing 30 to 50 parts by volume of propylene carbonate, 10 to 35 parts by volume of dimethyl carbonate, and 15 to 70 parts by volume of ethyl methyl carbonate per 100 parts by volume of the solvent; and
lithium bis(fluorosulfonyl)imide, as an electrolyte,
wherein the solvent consists essentially of the three compounds consisting of propylene carbonate, dimethyl carbonate, and ethyl methyl carbonate in a manner that the three compounds account for 90 parts by volume or more, of the 100 parts by volume of the solvent to the extent that capacitance and internal resistance of the lithium ion capacitor are not materially affected,
wherein the volume of ethyl methyl carbonate is 30% or more and 50% or less of a sum of the volume of dimethyl carbonate and the volume of ethyl methyl carbonate.

2. A lithium ion capacitor according to claim 1 , wherein a concentration of lithium bis(fluorosulfonyl)imide in the electrolytic solution is in a range of 1.0 to 1.6 mol/L.

Assignees

• Taiyo Yuden Kk

Inventors

• Tsuzuki Takeo

Classifications

• C01B21/086

  containing one or more sulfur atoms · CPC title

• H01G11/62

  characterised by the solute, e.g. salts, anions or cations therein · CPC title

• H01G11/06 Primary

  with one of the electrodes allowing ions to be reversibly doped thereinto, e.g. lithium ion capacitors [LIC] · CPC title

• H01G11/60 Primary

  characterised by the solvent · CPC title

• Y02E60/13

  Energy storage using capacitors · CPC title