1. Interaction between cathode and anode and its impact on the production of alkyl dicarbonates in lithium ion batteries
- Author
-
Gu-Yeon Kim
- Subjects
chemistry.chemical_classification ,020209 energy ,General Chemical Engineering ,Inorganic chemistry ,Diethyl carbonate ,chemistry.chemical_element ,02 engineering and technology ,Electrolyte ,Anode ,chemistry.chemical_compound ,chemistry ,0202 electrical engineering, electronic engineering, information engineering ,Electrochemistry ,Lithium ,Graphite ,Faraday efficiency ,Ethylene carbonate ,Alkyl - Abstract
A new simple storage experiment is introduced to show direct evidence of a cathode-anode interaction. The delithiated positive electrodes and/or the lithiated negative electrodes from Li[Ni 1/3 Mn 1/3 Co 1/3 ]O 2 /graphite and LiCoO 2 /graphite pouch cells are stored in Nalgene bottles (high-density polyethylene) filled with 1.0 M LiPF 6 in an ethylene carbonate: diethyl carbonate (EC:DEC, 1:2 v/v ratio) electrolyte for 2 weeks in an Ar-filled glove box at room temperature. During the storage experiment, the color change of the electrolyte, the formation of alkyl dicarbonates, and the decomposition of LiPF 6 are observed. The most important result of this storage experiment is that these reactions are significantly affected by the cathode-anode interaction. The electrolyte color change comes with slightly larger impedance growth during cycling and the alkyl dicarbonates improve coulombic efficiency. The decomposition of LiPF 6 is suppressed by the negative electrode. The experiment and results shown here will be helpful to those who want to research the cathode-anode interaction and improve the performances of Li-ion batteries.
- Published
- 2016