Scientists in Melbourne have developed a lithium- sulfur battery that has five times the capacity of lithium-ion batteries.
This battery holds 99 percent efficiency over 200 recharge cycles, and if you have it on your smartphone, you won’t need to charge your device for five days.
The problem with these batteries, however, is that the sulfur electrodes rot during the charge and discharge cycle, and the energy advantage is rapidly disappearing, says scientist Madokt Sheibani, who led a team of scientists from Australia.
“The electrode will break down and then the battery will shut down quickly,” she adds.
That’s because the sulfur electrode expands and shrinks during the cycle, with a volume change of about 78 percent. The change in volume also happens with electrodes on lithium-ion batteries that power electric cars and smartphones, but is about eight times smaller.
To prevent the electrodes from breaking down on a lithium-sulfur battery, researchers have given the sulfur particles more room to expand and shrink.
Usually lithium-sulfur batteries have materials that bind the particles together so that the battery does not explode when expanding. A smaller amount of polymer bonding material was used here at the electrode, thereby creating more distant structures between the sulfur particles.
Shaybaniyev says a lithium-sulfur battery would drastically reduce costs for electric cars and energy storage in general, as sulfur is a widespread and extremely inexpensive material.
However, lithium sulfur batteries may face similar ethical issues with lithium batteries.
Metal oxides in lithium ion batteries are usually nickel, cobalt or manganese, which are expensive and less expensive in nature. The problem is this: A significant percentage of cobalt, for example, comes from mining in Congo where children work.
Researchers will also test the battery prototypes in order to make them commercially available in Australia in the coming years.