Description: NASA scientific exploration missions require battery systems to power equipment and telecommunications critical to mission objectives. NASA’s mission profiles demand the highest achievable specific energy as well as operability under extreme conditions of temperature, vacuum, and radiation. While rechargeable battery technologies continue to advance the state-of-the-art to meet NASA’s needs, existing primary battery cell technologies (e.g. Li-CFx) can presently address NASA missions. However, maximizing the utilization of the stored energy will need improvements in state-of-charge (SoC) and state-of-health (SoH) determination/prediction. Li-CFx cells have attractive characteristics for NASA missions, including very high specific energy, self-heating during discharge, and radiation tolerance. However, discharge rate capability is limited, and the discharge voltage profile is only weakly correlated to SoC. Without accurate prediction of primary battery SoC, results of scientific missions (e.g. Europa) could be lost in space due to insufficient energy to transmit those results back to Earth. Alternatively, mission durations could be truncated due to overly conservative expectations of battery life. In either scenario, the return on NASA’s mission investment ranges from suboptimal to catastrophic. Improvements in Li-CFx modeling are needed to better determine and predict SoC to maximize NASA mission performance. Cornerstone Research Group proposes to continue development of an Advanced Primary Cell Model based on coupled thermodynamic and transport calculations combined and multiple monitoring inputs as feedback controls. The Advanced Primary Cell Model will enable NASA to maximize mission operations by optimally managing primary cell battery systems across mission operating conditions. The proposed program will build on Phase I results demonstrating high-fidelity single-cell modeling/simulation capability toward a prototype demonstration of a multi-cell battery.

Benefits: Primary cell battery monitoring and energy optimization for scientific missions Accurate primary cell SoC and lifetime determination/prediction over a wide temperature range

Battery cell development tool Military man-portable energy storage management Aerospace reserve battery management Medical device battery management