As the demand for increased energy density grows in the contemporary electric vehicle (EV) sector, lithium-ion batteries (LIBs) have emerged as the preferred choice within modern secondary battery technologies [1]. These batteries, owing to their remarkable characteristics, are valued for their outstanding energy density, enhanced specific energy efficiency, and high-performance metrics compared to alternative battery technologies [2]. With noticeable constraints becoming evident, endeavors are currently underway to discover effective solutions for commercial LIBs. These efforts primarily focus on advancing both cathode and anode electrodes to achieve high-energy density approaches. To attain this high energy density, the use of a dry-process technique is necessary. Dry processing offers several advantages over traditional solvent processes, particularly in terms of operational cost and energy efficiency, making it a promising alternative for electrode manufacturing in LIBs. Moreover, the absence of solvents allows to produce electrodes with higher mass loadings, potentially facilitating battery miniaturization. In this study, electrodes employing a solvent-free dry-process method were fabricated utilizing a blend of silicon and graphite as the anode material. Each step was meticulously optimized, particularly in the utilization of Polytetrafluoroethylene (PTFE) material, which is not typically used in electrode materials, resulting in significant advancements in alleviating potential issues. Building upon this, high-loading, high-density electrodes were successfully produced using the dry-process method. In this research, a current density of 6 mA/cm2 and an electrode density of 1.6 g/cc were successfully achieved using a dry process method. The manufactured electrode utilizes 20% silicon content to address the limitations of silicon oxide, achieving performance equal to or exceeding that of slurry state electrodes. These dry-process electrodes show potential to facilitate the development of lithium-ion batteries under harsh cell design conditions in the future. Reference s [1] Nano Energy, 2017. 31: p. 113-143.[2] Nature Chem 7, 19–29 (2015).
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