Executive Summary : | Lithium-ion batteries have proven successful in powering portable electronic devices and electric vehicles, but their cost, limited resources, safety, and environmental issues pose challenges for their future prospects. To address these issues, systems based on other metal ions, such as Na+, K+, Mg2+, and Zn2+, have gained interest due to their abundance and cost-effectiveness. Aqueous electrolytes, such as water-in-salt (WIS) electrolytes, offer advantages such as better safety, low cost, environment-friendliness, higher ionic conductivity, and less complex manufacturing conditions. The recent thermal runaway incidents in India have prompted the need for alternative safe and environment-friendly aqueous batteries. Aqueous Zn-ion batteries are an emerging technology to replace conventional Li-ion batteries due to their higher volumetric capacity, low redox potential, abundant reserves, non-toxicity, and multivalent charge transfer carrier. However, practical challenges such as cathode dissolution, dendrite formation, Zn corrosion, and side reactions can negatively impact the performance of these batteries. The proposed proposal aims to develop a fundamental understanding of stabilizing both cathode and anode in aqueous electrolytes to create high cell voltage aqueous Zn-ion batteries with long-term cyclability. This will be achieved through three directions: 1) developing ZnMn₂O₄ as a model cathode and modifying it with certain cation/anion and carbon materials to ease cathode dissolution and capacity fading; 2) developing WIS electrolytes and modifying them with additives and creating deep eutectic: water: salt solution (DES) as an alternative electrolyte; and 3) studying their effect on achieving a stable homogeneous SEI at Zn anode and CEI at cathode using in-situ/ex-situ tools. |