Tributyl borate as a novel electrolyte additive to improve high voltage stability of lithium cobalt oxide in carbonate-based electrolyte
Document Type
Article
Publication Date
1-1-2018
Abstract
Tributyl borate is used as a novel electrolyte additive to improve the stability of LiCoO2 cathode operating at a high charging-cutoff voltage. The HOMO energy calculation notes that Tributyl borate would be preferentially oxidized and then generate a more uniform, extremely stable, and lower resistance cathode solid electrolyte interphase (CEI) on the LiCoO2 surface. This CEI film can effectively suppress the subsequent decomposition of electrolyte and improve cyclic stability and discharge capability of LiCoO2 cathode. With the electrolyte contained 0.5 wt.% tributyl borate, the LiCoO2/Li cells achieve a capacity retention of 85.2% after 120 cycles at 3.0–4.4 V, comparing to the capacity retention of 37.7% for the cells without tributyl borate.
Keywords
Tributyl borate, Additive, High-voltage lithium-ion batteries, LiCoO2 cathode, Solid electrolyte interphase
Divisions
PHYSICS
Funders
National Natural Science Foundation of China ( 51474243 and 51574288 ),China Postdoctoral Science Foundation ( 2017M622598 ),Fundamental Research Funds for the Central Universities of Central South University ( 2018zzts429 )
Publication Title
Electrochimica Acta
Volume
276
Publisher
Elsevier
Additional Information
Yuncai Chen. Centre for Ionics University of Malaya, Department of Physics, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia.