Researchers in Australia say that advancements made in cathode durability could make lithium-sulfur batteries a reality for electric vehicles soon.
In both, researches say lithium-sulfur's lower weight and cheaper production costs would make those batteries attractive for transportation uses but up until now, lithium-sulfur batteries haven't been able to handle many charge-discharge cycles. That's because sulfur cathodes in those batteries swell with lithium ions during discharge cycles and contracts while charging, according to scientists. That leads to extreme cathode corrosion, which shortens the life-cycle for those batteries.
According to IEEE Spectrum, those cathodes fall apart in about 40 to 50 charge cycles.
The Monash University researchers say they've made a more robust cathode for lithium-sulfur batteries now, ones than can handle many more charge and discharge cycles, by increasing space for the cathodes by reducing the amount of binder used.
“This leaves increased space for accommodating the changes in the structure and the resultant stress,” mechanical and aerospace engineer Mahdokht Shaibani told IEEE Spectrum. “As a result, the sulfur electrode maintains its integrity over long-term cycling.”
The group's large pouch cells lasted for 100 cycles and the group says within two to four years they may have a battery viable for market uses.
Longer-lasting, higher-mileage batteries are one of the EV holy grails as automakers and suppliers race to create viable alternatives. Last year, researchers working with Tesla said they developed batteries in the lab that could withstand up to 6,000 charge cycles and last up to 1 million miles in vehicles, or up to two decades in power grids.