Lithium-sulfur battery by OXIS Energy. (Photo courtesy of OXIS Energy.)
High energy density batteries are often the only power source available for working autonomously in remote locations and harsh climates.
Unfortunately, battery systems are particularly susceptible to cold temperatures, which impact performance and reliability.
Currently in development, an ultra-low temperature battery project, based on lithium-sulfur (Li-S) battery technology, may offer a solution.
The new battery project aims to explore the feasibility of combining high energy density, low temperature electrolyte Li-S battery chemistry with packaging and control electronics that will enable reliable operation in some of the coldest and harshest environments in the world.
The resulting battery pack will lead to a follow-on mid-stage program to develop and produce a rechargeable high-energy density battery that will operate at temperatures as low as -80 degrees Celsius.
Li-S batteries are comprised of layers of a lithium metal anode, a nonflammable lithium sulfide electrolyte that improves safety and a sulfur-based cathode that includes carbon and a polymer binder.
This battery technology will be combined with an electronic battery management system (BMS) to provide automated cell balancing, pack health monitoring and protection.
The BMS will also control charging and will be able to automatically switch off the charger for safety. An inbuilt “fuel gauge” will provide continuous state of charge and state of health data.
“It is very difficult to secure the effective utilization of battery systems in extreme conditions, whether hot or cold,” said Huw Hampson Jones, CEO of OXIS Energy, one of the partners in the project. “OXIS Li-S cell technology can operate at up to 80 degrees Celsius, but to do so at the other extreme of -80 degrees Celsius is very challenging.”
Li-S chemistry has a theoretical energy density higher than Li-ion, according to OXIS. They have been developing Li-S cells for more than 10 years, and have managed to build cells that offer up to 300 Wh/kg.
Standard Li-S pouch cell from OXIS Energy. (Photo courtesy of OXIS Energy.)
They have also designed battery systems for a variety of applications including electric vehicles, energy storage and military use.
The successful completion of this project has the potential for a wide range of high energy density batteries for cold climate machine operation, vehicles and exploration.
For more on OXIS Energy Li-S battery technology, visit their website.