Evaluation of Commercial High Energy Lithium-Ion Cells for Aerospace Applications

As NASA missions become increasingly demanding of resilient, lightweight, and compact power sources, there is a continuous need to develop long-life and high energy battery systems. Lithium-ion batteries have been developed at JPL over the last several decades and have been successfully integrated into a number of NASA spacecraft, including rovers, landers, and satellites [1]. The environment of space and the nature of these missions present a unique set of challenges. Power may be required on an ongoing basis for years or even decades, and long cycle life and calendar life must be demonstrated. Extreme low-temperature exposure is to be expected, and cells must be able to operate at -20 °C to -50 °C depending on the thermal management employed. Resilience to high temperatures and operational capability at low temperatures without ‘lithium plating’ are serious issues in the space environment. Furthermore, all cell components must be able to withstand the radiation exposure expected during transit and operation in certain planetary (e.g., Jupiter) missions without damage [2]. At JPL, a significant effort has been devoted over the years to develop electrolytes for wide temperature Li-ion cells [3,4].

In addition to the development of custom-made large-format cells, NASA is interested in the assessment of small-format cells for certain applications due to gains in energy density of commercial cells, in particular in the 18650 format. Several manufacturers now offer 18650 cells with specific energies greater than 200 Wh kg^-1. However, these commercial cells are required to be validated for space missions, with extensive testing to demonstrate their performance, safety, reliability, and above all suitability for space environments. In addition, the use of small cells in large numbers, in contrast to custom-made large format cells, introduces additional requirements of cell-to-cell consistency to simplify their charge management.

In the present study, we have evaluated a number of commercial 18650 cells of varying capacities and manufacturers for possible future use in NASA deep space missions, including low temperature charge and discharge rate capability, cycle life and capacity retention over a range of temperatures, and tolerance to radiation exposure.

Acknowledgement

The work described herein was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration (NASA) and supported by the NASA’s Europa Clipper Mission (ECM) project.

References

[1] Ratnakumar, B. V., Smart, M. C., Huang, C. K., Perrone, D., Surampudi, S., & Greenbaum, S. G. (2000). Lithium ion batteries for Mars exploration missions. Electrochimica Acta, 45(8-9), 1513–1517. doi:10.1016/S0013-4686(99)00367-9

[2] Ratnakumar, B. V, Smart, M. C., Whitcanack, L. D., Davies, E. D., Chin, K. B., Deligiannis, F., & Surampudi, S. (2004). Behavior of Li-Ion Cells in High-Intensity Radiation Environments. Journal of The Electrochemical Society , 151 (4 ), A652–A659. doi:10.1149/1.1666128

[3] Smart, M. C., Ratnakumar, B. V, & Surampudi, S. (2002). Use of Organic Esters as Cosolvents in Electrolytes for Lithium-Ion Batteries with Improved Low Temperature Performance. Journal of The Electrochemical Society , 149 (4 ), A361–A370. doi:10.1149/1.1453407

[4] Smart, M. C., Hwang, C., Krause, F. C., Soler, J., West, W. C., Ratnakumar, B. V, & Amine, K. (2013). Wide Operating Temperature Range Electrolytes for High Voltage and High Specific Energy Li-Ion Cells. ECS Transactions , 50 (26 ), 355–364. doi:10.1149/05026.0355ecst