Graphene oxide as a sulfur immobilizer in high performance lithium/sulfur cells

Patent metadata

Field	Value
Publication number	US-9673452-B2
Application number	US-201214347600-A
Country	US
Kind code	B2
Filing date	Sep 28, 2012
Priority date	Sep 30, 2011
Publication date	Jun 6, 2017
Grant date	Jun 6, 2017

Abstract

The loss of sulfur cathode material as a result of polysulfide dissolution causes significant capacity fading in rechargeable lithium/sulfur cells. Embodiments of the invention use a chemical approach to immobilize sulfur and lithium polysulfides via the reactive functional groups on graphene oxide. This approach obtains a uniform and thin (˜tens of nanometers) sulfur coating on graphene oxide sheets by a chemical reaction-deposition strategy and a subsequent low temperature thermal treatment process. Strong interaction between graphene oxide and sulfur or polysulfides demonstrate lithium/sulfur cells with a high reversible capacity of 950-1400 mAh g −1 , and stable cycling for more than 50 deep cycles at 0.1 C.

First claim

What is claimed is:

1. A composition of matter comprising:
a graphene oxide-sulfur (GO-S) nanocomposite, wherein GO further comprises a plurality of functional groups and S is bonded to carbon atoms.

2. The composition of matter of claim 1 , wherein the plurality of functional groups includes at least one functional group selected from the group consisting of an epoxy bridge, a hydroxyl group, a phenol group, and a carbonyl group.

3. An electrode comprising:
a graphene oxide-sulfur (GO-S) nanocomposite, wherein the GO-S nanocomposite further comprises a plurality of functional groups and S is bonded to carbon atoms.

4. The electrode of claim 3 , wherein the plurality of functional groups includes at least one functional group selected from the group consisting of an epoxy bridge, a hydroxyl group, a phenol group, and a carbonyl group.

Assignees

• Univ California

Inventors

• Zhang Yuegang
• Cairns Elton J
• Ji Liwen
• Rao Mumin

Classifications

• H01M50/417

  Polyolefins · CPC title

• H01M10/0566

  Liquid materials · CPC title

• C01B31/26

  Chemistry & Metallurgy · mapped topic

• H01M4/625

  Carbon or graphite · CPC title

• C07D303/38

  with hydrocarbon radicals, substituted by carbon atoms having three bonds to hetero atoms with at the most one bond to halogen, e.g. ester or nitrile radicals · CPC title