Simulation and Analysis of Inhomogeneous Degradation in Large Format LiMn₂O₄/Carbon Cells

Abstract

Degradation phenomena are not distributed uniformly in a large-format cell. To better understand the inhomogeneous degradation in large-format cells, a two-dimensional model was developed for a LiMn2O4 (LMO)/Carbon cell. The model includes both the non-uniform porous electrode properties and the electrode mismatch. The simulation results show that when the anode edge is extended over the cathode edge, the LMO particles near the edge suffer larger potential difference, larger charge/discharge depth, and higher insertion-induced stress. Therefore, the predicted loss of LMO is more pronounced near the edge as has been seen experimentally. The influence of different design adjustable parameters (such as: the anode extension length, the capacity ratio, the porosity, and the electrode thickness) and electrolyte properties (such as: the diffusion coefficient and the ionic conductivity) on the cathode performance. Among them, the over-potential behavior of the cathode is most sensitive to the extent of the electrode mismatch. Larger anode extensions will increase the possibility of the LMO degradation at the cathode edge. This suggests that a longer extension of the anode is not better for improvement of cell life. An optimal design of the anode extension length should be carried out.

High Capacity and High Density Functional Conductive Polymer and SiO Anode for High-Energy Lithium-Ion Batteries

“…High CE is critical for the long-term stable cycling of the anode electrode and better capacity retention at the full cell level. 27,28 The first cycle CE is typically ∼62% (Supporting Information Table S2), which is comparable to most literature reports. Besides the formation of SEI, 29 lithium reacts and converts silicon oxide to silicate, which contributes to the large first cycle irreversible capacity.…”

Lithium Plating Detection Methods in Lithium-Ion Batteries

“…Subramanian [128][129][130][131][132] developed various reduction methods that enabled real-time simulations. White has applied various methods such as orthogonal decomposition [133] , state-space reformulation [134,135] , reducing the system of partial differential equations to ordinary differential equations [135,136] , and applying polynomial representations of the Li ion concentration in the solid phase [137] . In recent years, the popularity of these models [138][139][140][141][142][143][144][145][146][147][148][149] has increased due to their relative speed and accuracy.…”

Scalable process for application of stabilized lithium metal powder in Li-ion batteries

“…The explosion of technologies and products using Li-ion battery technology is causing manufacturers and consumers to demand higher and higher energy density and power output for portable electronic devices and electric vehicle applications [1][2][3][4][5][6]. Worldwide researchers are working to further improve Li-ion battery performance [7][8][9][10][11].…”