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The silicon (Si) offers enormous theoretical capacity as a lithium‐ion battery (LIB) anode. However, the low charge mobility in Si particles hinders its application for high current loading. In this study, ball‐milled phosphorus‐doped Si nanoparticles encapsulated with nitrogen‐doped carbon (P−Si@N−C) are employed as an anode for LIBs. P‐doped Si nanoparticles are first obtained via ball‐milling and calcination of Si with phosphoric acid. N‐doped carbon encapsulation is then introduced via carbonization of the surfactant‐assisted polymerization of pyrrole monomer on P‐doped Si. While P dopant is required to support the stability at high current density, the encapsulation of Si particles with N‐doped carbon is influential in enhancing the overall Li+ diffusivity of the Si anode. The combined approaches improve the anode's Li+ diffusivity up to tenfold compared to the untreated anode. It leads to exceptional anode stability at a high current, retaining 87 % of its initial capacity under a large current rate of 4000 mA g−1. The full‐cell comprising P−Si@N−C anode and LiFePO4 cathode demonstrates 94 % capacity retention of its initial capacity after 100 cycles at 1 C. This study explores the effective strategies to improve Li+ diffusivity for high‐rate Si‐based anode. [ABSTRACT FROM AUTHOR]

The demand for revolutionizing the lightweight design of Li‐ion batteries has become inevitable due to the ever‐increasing development of electric transportation modes. Integration of structural and energy storage functionalities into a single structural battery device can be a smart way to improve the overall performance of electric vehicles. In this study, we propose a facile and cost‐effective approach to develop a prospective anode for structural Li‐ion batteries through electrophoretic deposition of silicon (Si) particles onto polyacrylonitrile (PAN)‐based carbon fiber. The synthesis method is able to selectively deposit small‐sized silicon particles on the surface of carbon fiber, producing a thin, continuous, and porous coating of silicon nanoparticles on commercial PAN‐based carbon fiber. The synthesized Si/PAN‐based carbon fiber electrode exhibits remarkable mechanical properties, delivering a tensile strength of 2.57 GPa and a tensile modulus of 118.2 GPa. Benefitting from the morphology of the deposited silicon, the discharge capacity of silicon/PAN‐based carbon fiber anode can reach 565 mAh g−1 with 81 % capacity retention after 50 cycles. This work highlights the potential of silicon‐modified carbon fiber electrodes obtained via a simple and cost‐effective deposition method for structural Li‐ion battery applications. [ABSTRACT FROM AUTHOR]