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Lithium-ion batteries are widely used today due to their high energy density, long life cycles, and low self-discharge rates. It commonly uses graphite as an anode material with a high theoretical capacity of 372mAh/g. At the same time, several research groups explore ways to further increase the energy storage capacity of lithium-ion batteries by, for example, adding silicon to the graphite anode material. Silicon is naturally abundant and inexpensive, with low environmental impact and a significantly higher theoretical specific capacity of approximately 4200mAh/g. A drawback is that graphite-silicon composite anode materials tend to degrade during the charge/discharge cycles, leading to decreased storage capacity over time. This degradation is associated with the size of the silicon particles, where large, micrometer-sized silicon particles are more susceptible to instability than smaller, nanometre-sized particles. To address this issue, we present an investigation using laser-assisted processing of nano-graphite-silicon composites. This process uses low-cost micrometer-sized silicon particles mixed with nano-graphite powder and a 1064 nm continuous wave laser to process the nano-graphite-silicon-coated anode material under various conditions and atmospheres (ambient and nitrogen). The performance of the lithium-ion battery is affected by different processing conditions. Specifically, the intensity of the 0.25V and 0.5V anodic peaks, which indicate the delithiation of silicon, is particularly affected, with the inclusion of an additional broader shoulder peak at around 0.3-0.35V. Our investigation suggests that laser-assisted processing of nano-graphite-silicon-composite materials is a scalable concept with the potential to improve the performance of nano-graphite-silicon anodes for lithium-ion batteries.
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