Combined electrolyte-separator for rechargeable lithium-ion batteries withstands high temperatures

According to its developers at Rice University, Texas an essential part of the non-flammable, viscous composite is hexagonal boron nitride (h-BN).

The team led by materials scientist Pulickel Ajayan said batteries made with the composite functioned well in temperatures of 150 degrees Celsius (302 degrees Fahrenheit) for over a month with negligible loss of efficiency. Test batteries consistently operated from room temperature to 150 C, setting one of the widest temperature ranges ever reported for such devices, the researchers said.

"We tested our composite against benchmark electrodes and found that the batteries were stable for more than 600 cycles of charge and discharge at high temperatures," said lead author Marco-Túlio Rodrigues, a Rice graduate student.

The results were reported in Advanced Energy Materials.

In 2015 members of a Rice and Michigan-based Wayne State University team introduced an electrolyte made primarily of common bentonite clay that operated at 120 C. This year the team validated its theory that h-BN would serve the purpose even better.