Biomass-based three-dimensional network porous carbon anodes derived from discontinuous activation for high performance Li-ion batteries

An approach of discontinuous activation and frozon-dry pretreatment toward a three-dimensional network porous carbon was proposed by using apple as the carbon source. The porous carbon, characterized by its high surface area and abundant porosity, was optimized through the manipulation of temperature and activator quantities during the activation process. The sample obtained by first calcining at 500 °C and then at 800 °C shows ultra-high rate electrochemical performance of over 900 mA h g⁻¹ after 100 cycles and over 500 mA h g⁻¹ after 500 cycles under the condition of charging and discharging current density of 0.2 A g⁻¹ due to the high porosity. It is ascribed to the unique porous structure that can make the electrolyte and lithium ion transport and path short on the surface and inside the electrode material, further enhance its fast transport ability. The described approach represents an innovative and potentially impactful method for producing porous carbon electrodes with excellent electrochemical performance, particularly in the context of high-rate capability lithium-ion batteries.