Improved High-Voltage Stability of NCM523 Cathode Using Functional Electrolyte Additive

Wednesday, 4 October 2017
Prince George's Exhibit Hall D/E (Gaylord National Resort and Convention Center)
H. Q. Pham, J. H. Kim, H. Y. Lee (Chungnam National University, Republic of Korea), E. H. Hwang, Y. G. Kwon (Leechem Co., Ltd., Republic of Korea), and S. W. Song (Chungnam National University, Republic of Korea)
Advanced portable electronics, electric vehicles and grid-based energy storage systems demand higher energy density Li-ion batteries than conventional ones as power sources. The energy density of Li-ion batteries can increase by increasing the specific capacity of cathode material, which can increase by raising the charge cut-off voltage. Among various cathode materials, nickel-rich three-components layered oxides of Li(Ni1-x-yCoxMny)O2 (NCM, 1-x-y ≥ 0.5) have been considered as prospective candidates for high-energy density Li-ion batteries because of higher capacity and lower cost than Ni-lean oxides. However, their high-voltage performance is difficult to achieve due to limited anodic stability of conventional electrolyte above 4.2 V vs. Li/Li+ and instability of cathode material at highly charged state. Under such an aggressive charge condition, cathode-electrolyte interfacial reactions often cause a degradation of cathode material and electrolyte consumption by oxidative decomposition of electrolyte, resulting in a rapid performance fade.1-3 We have demonstrated that the use of high-voltage electrolyte additive(s) is efficient and economic because they in situ form a surface protective layer at the cathode during high-voltage cycling, and improve the interfacial stability and cycling performance.1-3

Here we report the development of phosphorus-based additive for the NCM523 cathode to the charge cut-off voltage of 4.6 V. X-ray photoelectron spectroscopic and infrared spectroscopic studies on cathode-electrolyte interfacial phenomena and their correlation to cycling performance would be discussed in the meeting.


This research was supported by Ministry of Trade, Industry & Energy (R0004645) and Creative Human Resource Development Consortium for Fusion Technology of Functional Chemical/Bio Materials of BK Plus program by Ministry of Education of Korea.


1. Y.-M. Lee, K.-M. Nam, E.-H. Hwang, Y.-G. Kwon , S.-W. Song, J. Phys. Chem. C, 118, 10631 (2014).

2. D. T. Nguyen, J. Kang, K.-M. Nam, Y. Paik, S.-W. Song, J. Power Sources, 303, 150 (2016).

3. J. Kang, H. Q. Pham, D.-H. Kang, H.-Y. Park, S.-W. Song, J. Alloys & Compds, 657, 464 (2016).