Interest in commercial off-the-shelf (COTS) cylindrical lithium-ion cells for NASA missions has increased in recent years due to their increasing performance and demonstrated reliability. There is particular interest in cells in the 18650 format, due to their wide availability from well-established vendors. Multiple commercial products are available, offering greater than 250 Wh∙kg^-1 and/or 3 kW∙kg^-1 at the cell level. High specific energy has made small cells competitive with heritage large-format prismatic lithium-ion cells for spacecraft power systems; high power capability could offer an alternative to thermal batteries in some applications.

The descent stage of the Europa Lander mission concept was baselined with a combination of a high specific energy lithium primary battery and thermal batteries to provide the required energy content and high-power pulse capability during deorbiting and landing. High specific energy and power lithium-ion cells could fulfill the functions of both of these, while also allowing for cell pre-screening and testing, unlike primary or thermal batteries. In support of this concept and future NASA missions, we have performed extensive evaluation of the components and performance characteristics of a number of COTS 18650 Li-ion cells, including destructive physical analysis, cycle life, rate capability, and ionizing radiation tolerance.

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. Support from the Europa Lander Mission concept and the NASA Engineering Safety Commission is gratefully acknowledged. Pre-Decisional Information – For Planning and Discussion Purposes Only.