Thermal battery for aircraft emergency power

The authors undertook the development of a thermal battery system to supply aircraft emergency power. The system was developed as an alternative to the oxygen-methanol or hydrazine emergency systems. Two batteries were developed: TB1 to provide power to an electrohydraulic pump and TB2 to provide power to aircraft electronics. For both batteries the LiAl/FeS₂ system was used, along with ternary electrolyte (LiCl-LiBr-LiFl). The reasons for utilizing thermal batteries in this application are threefold: first, thermal batteries have lower maintenance requirements than the hydrazine and oxygen-methanol systems; second, they are environmentally less hazardous than the hydrazine and oxygen-methanol systems; and, third, they are able to provide the required power with a fast risetime at the environmental temperature extremes. The performance shows the feasibility of very large, high energy density thermal batteries for new applications as emergency power systems