Metal‐Organic Framework Hosted Silicon for Long‐Cycling, Low‐Cost, and Flexible Batteries

Abstract Developing biodegradable electrodes is a significant step toward environmental sustainability and cost reduction in battery technology. This paper presents a new approach that utilizes metal‐organic framework (MOF)‐encapsulated silicon nanoparticles (SiNPs) as the active anode material within a cellulose‐based electrode. The electrode is free‐standing, flexible, biodegradable, and significantly reduces the strain experienced by SiNPs during volume expansion, resulting in improved capacity and cycle life stability of SiNPs. The high porosity of the electrode creates efficient lithium (Li + ) ion transport channels and enhances electrolyte absorption, thus promoting effective contact between the electrolyte and active material. The outcome is rapid electrode kinetics and a highly reversible discharge capacity of 1744.6 mAh g −1 at 0.5 A g −1 versus Li/Li + over 1000 cycles. Further, full cell tests are conducted that demonstrate a stable cycle performance exceeding 3400 cycles, with an initial discharge capacity retention of 80.5% at 0.5 A g −1 . By employing cellulose and avoiding toxic organic solvents and binders, the proposed approach is promising for a substantial reduction of the production costs of Li‐ion batteries. The scalability of the proposed method further enhances its practical viability, offering intriguing economic implications for the future of battery technology.