Optimization of Electrochemical Presodiation Parameters of Na‐Ion Full Cells for Stable Solid–Electrolyte Interface Formation: Hard Carbon Rods from Waste Firefighter Suits

Utilizing the synthetic waste of firefighter costumes, rod‐shaped hard carbon materials are effectively produced for the first time with over 99% purity, and their structural properties are evaluated using the appropriate spectroscopic techniques. The galvanostatic cycling tests are performed at different temperatures and the result shows that the capacity and capacity fade values are directly affected by the temperature. The high‐rate consumption of sodium ions during the evolution of the solid–electrolyte interface in the first cycle of the cells is observed and the highest capacity of the half cells is obtained as 410 and 233 mAh g −1 for the first and second cycles, respectively. To compensate for the sodium‐ion loss, an electrochemical treatment presodiation technique is implemented, which is an effective means of compensating for the initial inefficiency. The optimum presodiation condition of electrochemical treatment of anode electrode for the production of Na 0.67 Mn 0.5 Fe 0.45 Ti 0.07 O 2 /presodiated hard carbon full cells is investigated. The highest capacity values for C/10 are obtained at 114.9 mAh g −1 for the full cells using the voltage window of 2–4 V. The cost analysis of the battery pack for 90 kW electric‐powered cars is calculated by the BatPaC software and the results are evaluated for possible commercialization.