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As the demand for mobile energy storage devices has steadily increased during the past decades due to the rising popularity of portable electronics as well as the continued implementation of electromobility, energy density has become a crucial metric in the development of modern batteries. It was realized early on that the successful utilization of silicon as negative electrode material in lithium‐ion batteries would be a quantum leap in improving achievable energy densities due to the roughly ten‐fold increase in specific capacity compared to the state‐of‐the‐art graphite material. However, being an alloying type material rather than an intercalation/insertion type, silicon poses numerous obstacles that need to be overcome for its successful implementation as a negative electrode material with the most prominent one being its extreme volume changes on (de‐)lithiation. While, as of today, a plethora of different types of Si‐based electrodes have been reported, a universally common feature is the interface between Si‐based electrode and electrolyte. This review focuses on the knowledge gained thus far on the impact of different liquid electrolyte components/formulations on the interfaces and interphases encountered at Si‐based electrodes. [ABSTRACT FROM AUTHOR]

Summary: In situ growing conductive polyaniline (PANi) has been regarded as a functional binder to enhance the performance of silicon based anodes in half cells, while few papers discussing the influence of Mn2+ from cathode on full cells. In this paper, the effects of Mn2+ on NSi@PANi electrodes in both half and full cells are investigated, and the mechanism for the fast capacity fade of LiMn2O4/NSi@PANi full cell is elucidated. Results reveal that the full cell will significant accelerate the capacity fade of NSi@PANi anode, and the extra consumption of active Li+ and electrolytes caused by the deposited Mn2+ on silicon anodes in lithium manganate (LMO)/NSi@PANi full cells is confirmed as the main reason of the capacity fade and lower coulombic efficiency for the excessive growth of solid electrolyte interphase. [ABSTRACT FROM AUTHOR]

To understand the effect of a polydopamine interlayer between a copper current collector and a silicon composite electrode, a physics‐based model is used to analyze the cycle performance of silicon‐based lithium‐ion half‐cells with bare and polydopamine‐treated copper current collectors. We investigate the capacity‐fading mechanisms of the two cell configurations by analyzing the model parameters that change with cycling. The major capacity‐fading mechanisms in the silicon‐based anodes are the increase in film resistance (solid electrolyte interphase resistance and contact resistance) and the isolation of silicon active material. The polydopamine interlayer reduced the contribution of the film resistance and isolation of the silicon active material to the capacity fade by 22 % and 10 %, respectively. The insulating‐nature of the polydopamine interlayer resulted in an increase in the charge transfer resistance contributing to 15 % reduction in the capacity retention. The efficacy of the physics‐based model is validated with experimental data obtained from silicon‐based half‐cells with bare and polydopamine‐treated copper current collectors. [ABSTRACT FROM AUTHOR]