Smartphones and electric cars have seen serious technological advancements in recent years, but poor battery life still plagues these devices. No matter how efficient the operating system of your phone, you probably still need to plug it in to charge at least once a day. The lithium-ion batteries we use to power our devices have become much more advanced, but as smartphones, electric cars, and solar grids get even more advanced in the future, they’ll need even better batteries that can power them for longer. Australian researchers may have the solution: a lithium-sulfur battery that they say will be able to power a smartphone for five days straight.
Currently, lithium-ion batteries dominate the power market. Though they are rechargeable, lithium-ion batteries can only store a limited amount of energy. Experts have known that lithium-sulfur, or Li-S, batteries can store a lot more power—sulfur allows for a higher charge capacity and, perhaps more importantly, is cheaper than the components currently used in lithium-ion batteries, which rely on materials such as nickel and cobalt. But until now, Li-S batteries haven’t been able to maintain their high-energy performance over time because the sulfur electrode, which expands and contracts during power cycles (the process of a battery going from fully charged to completely empty, and then back to fully recharged), tends to break apart over repeated charging cycles, killing the battery quickly.
Now, though, Monash University researchers have successfully fabricated and patented a Li-S battery that they say doesn’t have the same issue, and they’re in the process of commercializing it. Mahdokht Shaibani and her team reconfigured the sulfur cathodes so they can accommodate higher stress without cracking by giving the sulfur particles more space to expand and contract.
The result is a battery that doesn’t see a drop in capacity or performance over short periods of time; researchers say this Li-S battery keeps a 99% efficiency for more than 200 cycles. It’s difficult to put this in perspective since there aren’t any Li-S batteries currently available on the market, but according to a 2017 paper published in the journal Energies, Li-S batteries at that time had a “typical cycle life,” or the number of complete charges a battery can support before its capacity falls under 80%, that rarely exceeded 100 cycles. Basically, you could only recharge them 100 times before they stopped holding as much power as they initially could.
With this new battery, your smartphone could stay charged for five consecutive days, according to the researchers. It could also power an electric vehicle for more than 600 miles on a single charge. Currently, eight electric vehicle models can drive more than 200 miles on a single charge, with the Tesla Model S topping the list with the ability to go 370 miles on one charge; other manufactured EVs tap out around 250 miles. (The revamped Tesla Roadster, for which production is set to start in 2020, will reportedly have a 620-mile range from its battery pack.) Shaibani sees the Li-S battery as something that will transform how phones, cars, computers, and even solar grids are manufactured in the future. “Our research team has received more than $2.5 million in funding from government and international industry partners to trial this battery technology in cars and grids from this year,” she says in a statement.
This Li-S battery would also be cheaper to produce, have a smaller environmental footprint than those currently on the market, and lead to less hazardous waste, the researchers say. As Shaibani told New Scientist, “In order to have much cheaper energy and more ethical batteries, we need a radically new energy storage system.” Some of the world’s largest lithium battery manufacturers in China and Europe have said they’re interested in upscaling production of these Li-S batteries, according to Monash University, and further testing of them will take place in Australia early this year.