New material could significantly extend the lifespan of lithium batteries

New material could significantly extend the lifespan of lithium batteries

Researchers at the Hong Kong University of Science and Technology have developed a new material that could address one of the central challenges facing lithium-metal batteries: dendrite formation, which causes short circuits and battery degradation.

Single-crystal framework for lithium batteries

The team produced a single-crystal bulk borate covalent organic framework (COF) - an ideally ordered molecular “construction set” assembled into one continuous crystal lattice - that functions as a solid-state electrolyte. Unlike most existing polycrystalline COF structures, the new material contains organised ion-transport channels and enables more even lithium deposition. According to the researchers, this helps inhibit dendrite growth, improves stability and makes batteries safer.

Capacity retention and charging efficiency

In full cells using a LiFePO4 cathode, the batteries retained 91.8% of their capacity after 600 cycles, while Coulombic efficiency reached 99.98%. In other words, almost all of the energy “put into” the battery during charging is actually recovered during discharge. The scientists believe this structure could represent an important advance towards practical solid-state lithium-metal batteries for electric vehicles, energy storage and other systems where high energy density and long service life are particularly important.