Post by treptoplax on Apr 23, 2018 16:05:46 GMT
Here's a RTG alternative that could have lower mass:
en.m.wikipedia.org/wiki/Optoelectric_nuclear_battery
The radiation source is in a gas and we capture the energy with photoelectric cells instead of thermocouples. Large radiators are thus not required, and efficiency is theoretically high.
"The battery would consist of an excimer of argon, xenon, or krypton (or a mixture of two or three of them) in a pressure vessel with an internal mirrored surface, finely-ground radioisotope, and an intermittent ultrasonic stirrer, illuminating a photocell with a bandgap tuned for the excimer.[1] When the beta active nuclides (e.g., krypton-85 or argon-39) emit beta particles, they excite their own electrons in the narrow excimer band at a minimum of thermal losses that this radiation is converted in a high band gap photovoltaic layer (e.g. in p-n diamond) very efficiently into electricity. The electric power per weight compared with existing radionuclide batteries can then be increased by a factor 10 to 50 and more. If the pressure-vessel is carbon fiber/epoxy the weight-to-power ratio is said to be comparable to an air-breathing engine with fuel tanks. The advantage of this design is that precision electrode assemblies are not needed, and most beta particles escape the finely-divided bulk material to contribute to the battery's net power."
en.m.wikipedia.org/wiki/Optoelectric_nuclear_battery
The radiation source is in a gas and we capture the energy with photoelectric cells instead of thermocouples. Large radiators are thus not required, and efficiency is theoretically high.
"The battery would consist of an excimer of argon, xenon, or krypton (or a mixture of two or three of them) in a pressure vessel with an internal mirrored surface, finely-ground radioisotope, and an intermittent ultrasonic stirrer, illuminating a photocell with a bandgap tuned for the excimer.[1] When the beta active nuclides (e.g., krypton-85 or argon-39) emit beta particles, they excite their own electrons in the narrow excimer band at a minimum of thermal losses that this radiation is converted in a high band gap photovoltaic layer (e.g. in p-n diamond) very efficiently into electricity. The electric power per weight compared with existing radionuclide batteries can then be increased by a factor 10 to 50 and more. If the pressure-vessel is carbon fiber/epoxy the weight-to-power ratio is said to be comparable to an air-breathing engine with fuel tanks. The advantage of this design is that precision electrode assemblies are not needed, and most beta particles escape the finely-divided bulk material to contribute to the battery's net power."
