Effect of the succinonitrile additive, electrode processing, and N/P ratios in the performance of high‐voltage lithium‐ion batteries using LiNi0.5Mn1.5O4 cathode

Abstract

AbstractThe progressive improvement in the gravimetric energy density of lithium‐ion batteries (LIBs) leads to electrolyte design, positive electrode, and full‐cell optimization processes. The spinel lithium nickel manganese oxide (LiNi0.5Mn1.5O4, LNMO) is one of the potential candidates for the next generation of LIBs applied for electric vehicles due to high working potential (4.75 V vs. Li+/Li), affordable price, and environmental friendliness. Nevertheless, the degradation of cycling performance at high potential induces massive challenges for commercializing LNMO‐based batteries. This study investigated the impact of succinonitrile (SN), electrode processing, and N/P ratios to strengthen the LNMO half‐cell and graphite||LNMO full‐cell performance. According to the performance in half‐cell, the sample contained 85 wt% LNMO: 7.5 wt% C65: 7.5 wt% PVDF/NMP combining with the electrolyte 1.5 M LiPF6 in EC:EMC:DMC (2:1:7 – v/v) at 0.5 wt% SN seems to be the optimal condition for further full‐cell. In addition, the full‐cell with N/P = 1.3 displays a remarkable initial capacity of 118.75 mAh g−1, a Coulombic efficiency of 91.64%, and a superior gravimetric energy density of 537.71 mWh g−1. Moreover, it maintains a capacity retention of around 58% at the current density of 0.1C after 100 cycles. As a result, this study presents an optimal solution to augment the material's potential for commercialization in the immediate future.