Oxidation processes on conducting carbon additives for lithium-ion batteries
The oxidation processes at the interface between different types of typical carbon additives for lithium-ion batteries and carbonates electrolyte above 5 V versus Li/Li+ were investigated. Depending on the nature and surface area of the carbon additive, the irreversible capacity during galvanostatic cycling between 2.75 and 5.25 V versus Li/Li+ could be as high as 700 mAh g−1 (of carbon). In the potential region below 5 V versus Li/Li+, high surface carbon additives also showed irreversible plateaus at about 4.1–4.2 and 4.6 V versus Li/Li+. These plateaus disappeared after thermal treatments at or above 150 °C in inert gas. The influence of the irreversible capacity of carbon additives on the overall performances of positive electrodes was discussed.
KeywordsLithium-ion batteries Conductive additives High voltage positive electrode Electrolyte stability window Solid electrolyte interphase
The study was partially supported by the Global Climate and Energy Project at Stanford and King Abdullah University of Science and Technology (KAUST) under the award No. KUS-l1-001-12. We thank Heather Deshazer and Dr. Jang Wook Choi for experimental assistance.