Proton and hydrogen formation by cyclohexyl benzene during overcharge of Li-ion batteries

Hochun Lee, Soojin Kim, Jongho Jeon, Jeong Ju Cho

Research output: Contribution to journalArticlepeer-review

26 Scopus citations

Abstract

This study provides experimental evidence for proton and hydrogen formation caused by the anodic electropolymerization of cyclohexyl benzene (CHB), which is a popular electrolyte additive for overcharge protection of lithium-ion batteries (LIBs). It is found that considerable H2 evolution is observed in overcharged LiCoO2/graphite cells, especially when CHB is included as an electrolyte additive. In order to confirm the proton generation during the CHB oxidation, Pt/Pt-rotating ring disc electrode (RRDE) measurements are performed in 1 M Li(C2F5SO2)2N ethylene carbonate/ethyl methyl carbonate (1/2, v/v) solutions with and without CHB. The cathodic ring current is intimately correlated to the anodic disc current, and the cathodic reaction at the ring is determined to be the reduction of the proton. The proton generation efficiency during the CHB oxidation is as high as 90%. Proton liberation is also observed during the anodic decomposition of the electrolyte solvents, although it occurs in a much less stoichiometric way compared with that during the CHB oxidation.

Original languageEnglish
Pages (from-to)972-978
Number of pages7
JournalJournal of Power Sources
Volume173
Issue number2 SPEC. ISS.
DOIs
StatePublished - 15 Nov 2007

Keywords

  • Cyclohexyl benzene
  • Hydrogen
  • Lithium-ion battery
  • Overcharge
  • Proton
  • Rotating ring disc electrode

Fingerprint

Dive into the research topics of 'Proton and hydrogen formation by cyclohexyl benzene during overcharge of Li-ion batteries'. Together they form a unique fingerprint.

Cite this