Thermal control for energy storage in extreme environments

Robotic science rovers operating on the lunar surface over diurnal cycles face extreme temperature environments (-200 to 120 deg;C) beyond conventional energy storage batteries operating limits, even with shielded and articulated radiator assemblies. These hot and cold lunar conditions can last several Earth days, because of the slow rotation of the Moon, or permanently in shadowed craters and poses the significant challenges to small, low-power (~100 W or less) payloads, rovers, and landers required for lunar science, and survivability of the rovers electrical power subsystems during lunar day/night becomes a critical issue. As such, one strong technology candidate for meeting future lunar electrical storage thermal management needs are ThermoElectric Coolers (TECs) which are a well-established technology (gt; $1.1B market in 2021). TECs are solid-state, lightweight, have no moving parts or working fluids, and operate with highly reliable, uninterrupted, low maintenance, and environmentally-friendly cooling. Toward this goal, Nanohmics team proposes to develop a TEC system suitable for lunar electric power subsystems cooling during lunar day, and high-efficiency heating during the lunar night. The proposed Thermoelectric Temperature Regulation Unit (ThermoTruTM) will employ modular printed circuit boards (PCBs) based TEC devices that can be configured to meet thermal power dissipation shortcomings to address the lunar day cooling needs (radiator T = 30 ndash; 35 deg;C, ∆T gt; 15 deg;C, 10 ndash; 100 W of heat lift) and lunar night heating needs (electronics at gt; -20deg;C, ∆T to radiator gt; 20 deg;C, and radiator T ~ -50 deg;C) for small rover EPS survivability. A lunar night heating subsystem for small rovers currently does not exist. Using the combined benefits of compact cooling (day) and efficient heating (night) in a single, all-passive (i.e. no mechanical thermal switch) has numerous benefits for lunar rover and other lunar surface systems.