Materials scientists at Rice University (Houston, TX) have introduced a combined electrolyte and separator for rechargeable lithium-ion batteries that claims to supply energy at usable voltages and in high temperatures. The project used hexagonal boron nitride as a key element in an electrolyte and separator that allows lithium-ion batteries to withstand long stretches in temperatures up to 150 degrees Celsius.

Batteries made with the composite functioned perfectly in temperatures of 150 degrees Celsius for more than a month with negligible loss of efficiency. Test batteries consistently operated from room temperature to 150 degrees C, setting one of the widest temperature ranges ever reported for such devices, the researchers said. The results were reported in the publication Advanced Energy Materials.

Last year members of a Rice and Wayne State University team introduced an electrolyte made primarily of common bentonite clay that operated at 120 degrees C. In 2016 the team validated its hunch that h-BN would prove even better.
Batteries with the electrolyte are geared toward industrial and aerospace applications. In particular, oil and gas companies require robust batteries to power sensors on wellheads.