Tailoring Electrolytes for Extreme Temperatures in Rechargeable Aluminum and Lithium-Ion Batteries

<p>As the world moves toward greater electrification and sustainability, the demand for advanced energy storage technologies continues to grow. Batteries are essential for balancing energy supply and demand across applications ranging from portable electronics to electric vehicles and grid-scale renewable energy systems. However, current lithium-ion batteries (LIBs), while commercially successful, are typically limited to operating near ambient temperatures (typically, < 50 °C), restricting their use in extreme environments such as deep subsurface exploration or space missions, where temperatures can exceed 100 °C. At elevated temperatures, LIB performance and safety deteriorate due to accelerated degradation of cell components—especially the thermally unstable electrolytes based on LiPF₆—which leads to capacity fade, transition metal leaching, and increased risk of failure. These challenges underscore the need for new electrolyte systems that are both thermally and electrochemically stable under extreme conditions.</p> <p>In parallel, rechargeable aluminum batteries are gaining attention as potential alternatives to LIBs due to aluminum's high theoretical capacity, abundance, safety, and low cost. Yet, the development of practical Al batteries has been limited by the lack of suitable electrolytes that support reversible aluminum electrodeposition at room temperature. Chloroaluminate ionic liquids—formed from AlCl₃ and imidazolium-based chloride salts—remain the benchmark, but they are costly and highly corrosive. Recent efforts have explored deep eutectic solvents (DES) or ionic liquid analogues (ILAs) as more environmentally friendly and affordable alternatives. However, these systems often suffer from lower ionic conductivity and narrower electrochemical windows.</p> <p>This work aims to bridge these electrolyte challenges by designing ILAs and mixed-solvent electrolytes with different additives and compositions to enhance ionic conductivity, suppress crystallization, and improve performance across a broader temperature range, including Al electrolytes for low-temperature operation down to –40 °C and Li-ion electrolytes for up to 100 ^oC. The approaches detailed in this work provide new insights into tailoring electrolyte structure and composition for advanced battery systems while informing strategies to enhance the thermal resilience of rechargeable batteries in extreme environments.</p>

Name thesis:degree_name

Doctor of Philosophy (Ph.D.)

Level thesis:degree_level

Thesis

Discipline thesis:degree_discipline

Chemical Engineering

Year dc:date.available

2025

Author dc:creator

• Wang, Jonah

Contributors dc:contributor

• Robert J. Messinger

• electrolytes
• batteries
• electrochemistry
• Chemical Engineering

Repository record dc:identifier

https://academicworks.cuny.edu/cc_etds_theses/1259

OAI identifier oai:identifier

oai:academicworks.cuny.edu:cc_etds_theses-2352