Understanding the Nature of Capacity Decay and Interface Properties in Li//LiNi0.5Mn1.5O4 Cells by Cycling Aging and Titration Techniques

• DOI: 10.1021/acsaem.0c00614
• Publication Date: 2020-06-01T20:25:00Z
• Authors: Sara Ahmad J. A. ...; Md Ruhul Amin; Ramesh Kumar Petla; Umair Nisar; Rachid Essehli; Said Ahzi; Ilias Belharouak
• Keywords: State of charge; Ohmic contact; Capacity loss

The spinel structure LiNi0.5Mn1.5O4 (LNMO) is a propitious cathode material for next-generation lithium-ion batteries fast charge–discharge applications, but its capacity decay mechanism and rate-limiting process are not yet well understood. In this study, electrochemical impedance spectroscopy (EIS) with galvanostatic intermittent titration (GITT) cycling aging techniques were employed to investigate the nature of in disordered-phase LNMO. Different resistive components separated after every 10 cycles. Cell overvoltages (ΔVs) due ohmic conduction, charge transfer (CT), concentration polarization (CP) individually determined. Results revealed that cell exhibited higher ΔV at discharged state. However, value CP was state (SOC), overall LNMO/electrolyte interface played major role rate-determining step. Battery life estimated based on results. calendar found be more vulnerable than cycle life. also indicated working SOC range could optimized resistance analysis by avoiding those SOCs have most detrimental impact (e.g., heat generation fire hazard).