Effective dual‐layer fabrication solution for the lateral axial failure of the electrode in lithium‐ion batteries

Abstract

Lithium-ion batteries (LIBs) necessitate well-balanced performance characteristics, high energy/power density, and cyclability. In order to optimize them, several types of active materials are mixed in the electrode. In this study, LiNi 1/3 Co 1/3 Mn 1/3 O 2 (NCM333) with long cycle life and LiNi 0.8 Co 0.1 Mn 0.1 O 2 (NCM811) with high energy density are controlled as a dual layer or a mixture to improve the electrochemical performance of the electrode. We discovered that during cycling, the active materials in the surface layer facing the electrolyte have less polarization. The state of charge is greater than the average value of the whole electrode. In this regard, the electrode's dual-layer coating, which consists of a top layer of NCM333 and a bottom layer of NCM811, is the optimal structure among the various NCM811 and NCM333 combinations used in electrodes. As the charging current increases, this lateral failure mode accelerates.

Improved Performance of Lithium-Ion Batteries using a Multilayer Cathode of LiFePO4 and LiNi0.8Co0.1Mn0.1O2

“…The active particles at the top of the thick electrode experiences a wider change in state of charge (SOC) than that at the bottom. Therefore, the particles at the top of the electrode are cracked earlier than the particle at the bottom during cycling, leading to blocking the pores in the electrode and increasing the resistance against Li-ion diffusion in the pore network of electrode [23,24]. Hence, a new thick electrode design should be proposed to achieve a high energy density of LIBs while considering the mechanical fragility of the cathode materials according to the SOC.…”