Unlocking microwatt power: enhanced performance of Fe–V–Al thin films in thermoelectric microgenerators

Microwatt power output was obtained in thermoelectric microgenerators based on cost-effective and non-toxic Fe–V–Al thin films deposited by a DC magnetron co-sputtering process. A maximum electrical power of almost 5 μW at a temperature difference of 134 K was measured. This result leads to a maximum power density of 58.5 ± 6 mW cm−2, which is among the highest values obtained by a microdevice. Contrary to what is observed for other thermoelectric materials like Bi2Te3 or PEDOT composites, the performances of the present devices, assembled with junctions between Fe–V–Al and aluminum electrodes, are weakly impacted by their contact resistance. These results are very encouraging for the development of new architectures based on low-resistance Fe–V–Al thin films to power autonomous sensors in the Internet of Thing domain

Fabrication and characterization of polymer membranes with integrated arrays of high performance micro-magnets

International audienc

Long flexible melt-spun Ni–Co–Mn–In ribbons with shape memory effect and caloric perfomances above 300 K

International audienc

15 K liquid hydrogen thermal Energy Storage Unit for future ESA science missions

International audienceA thermal Energy Storage Unit (ESU) using liquid hydrogen has been developed as a solution for absorbing the heat peaks released by the recycling phase of a 300 mK cooler that is a part of the cryogenic chain of one of ESA's new satellites for science missions. This device is capable of storing 400 J of thermal energy between 15 and 16 K by taking advantage of the liquid-to-vapor latent heat of hydrogen in a closed system. This paper describes some results obtained with the development model of the ESU under different configurations and using two types of hydrogen storage: a large expansion volume for ground testing and a much more compact unit, suitable for space applications and that can comply with ESA's mass budget