Secondary batteries, unlike primary batteries, have experienced rapid growth as batteries that can be recharged and reused after discharge, such as those used in electric vehicles. As the market grows, the increasing prices of rare metals such as lithium, cobalt, and nickel, which are key raw materials for lithium secondary batteries, are putting significant pressure on battery manufacturers and automobile manufacturers. Sodium, the fourth most abundant element on Earth, is gaining attention for its potential to increase price competitiveness and enable the recycling of materials without emitting carbon dioxide in sodium-ion batteries. In this study, we fabricated secondary battery electrodes composed of metal-carbon using a composite anode material consisting of tin and hard carbon, and evaluated the electrochemical properties of these electrodes. The metal-hard carbon composite material exhibited a high discharge capacity of 559.6 mAh/g and an initial Coulombic efficiency of 90.74% after one cycle. Compared to electrodes using only hard carbon, the discharge capacity increased by approximately 200%, while maintaining a Coulombic efficiency of 90% without degradation. Even after 100 cycles of charging and discharging at a current density of 0.4 mA/cm², the long life performance of maintaining 90% or more of C.R. compared to the initial stage was stably operated. Also, Hard carbon has a volume capacity of 1.5mAh/cm², but Metal-hard carbon composite material has a volume capacity of 2.1~2.4mAh/cm², hence increasing the energy density of the sodium battery. The metal-hard carbon composite material produced in this study is considered suitable for application as a sodium battery anode material due to its excellent Coulombic efficiency, high capacity characteristics, and outstanding long-term stability.Keywords: Tin, Hard carbon, metal-carbon, metal composite, sodium battery, sodium ion, Na, secondary battery
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