Effects of vinylene carbonate and 1, 3-propane sultone on high-rate cycle performance and surface properties of high-nickel layered oxide cathodes. (December 2020)

• Record Type: Journal Article
• Authors: Oh, Jimin; Kim, Jumi; Lee, Yong Min; Kim, Ju Young; Shin, Dong Ok; Lee, Myeong Ju; Hong, Seungbum; Lee, Young-Gi; Kim, Kwang Man
• Is Part Of: Materials research bulletin. Volume 132(2020)
• Publication Date: 2020-12
• Subjects: Li(Ni-Co-Mn)O2 cathode materials -- Vinylene carbonate -- 1, 3-Propane sultone -- Electrochemical performance -- X-ray photoelectron spectroscopy; Materials -- Periodicals; Crystal growth -- Periodicals; Matériaux -- Périodiques; Cristaux -- Croissance -- Périodiques; Crystal growth; Materials; Periodicals; 620.11
• DOI: 10.1016/j.materresbull.2020.111008
• Languages: English
• ISSNs: 0025-5408

Abstract

Graphical abstract: Highlights: The high-rate electrochemical performance of NCM333, NCM622, and NCM811 is compared. The effects of VC and PS as electrolyte additives are evaluated. Cathode SEI on the NCM materials are analyzed by XPS. Abstract: The high-rate half-cell performance of LiNi0.3 Co0.3 Mn0.3 O2 (NCM333), LiNi0.6 Co0.2 Mn0.2 O2 (NCM622), and LiNi0.8 Co0.1 Mn0.1 O2 (NCM811) cathode materials is investigated with the base electrolyte of LiPF6 /ethylene carbonate (EC):ethylmethyl carbonate (EMC) and the additives of vinylene carbonate (VC) and 1, 3-propane sultone (PS). The effects of these additives on the cathode surfaces are particularly examined in terms of the reduction products of the electrolyte components and the formation of solid electrolyte interphase (SEI) on cathode surfaces. The cathode SEI appears less after formation for all NCM materials, but it accumulates with repeated charging/discharging at a high rate. Of these, the addition of VC + PS to the base electrolyte sufficiently provides stable cathode SEI with suppressed thickness under cycling at a high rate by inhibiting the further decomposition of reduction products. The synergy of VC + PS may be originated by the combination of vinyl and sulfone functional groups to provide passivation film with cross-linked protective networks on Ni-rich NCM cathode materials. Thus, superior cycle performance is achieved, especially for NCM811.