Energy

Stable lithium-sulfur battery could see smartphones run for 5 days

Stable lithium-sulfur battery ...
Dr Mahdokht Shaibani (center) led the development of a new lithium-sulfur battery that could power an electric car over 1,000 km without recharging
Dr Mahdokht Shaibani (center) led the development of a new lithium-sulfur battery that could power an electric car over 1,000 km without recharging
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Scientists have used a new type of bond to hold key components of lithium-sulfur batteries together during charging
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Scientists have used a new type of bond to hold key components of lithium-sulfur batteries together during charging
Dr Mahdokht Shaibani (center) led the development of a new lithium-sulfur battery that could power an electric car over 1,000 km without recharging
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Dr Mahdokht Shaibani (center) led the development of a new lithium-sulfur battery that could power an electric car over 1,000 km without recharging

Batteries made with a lithium-sulfur chemistry rather than the typical lithium-ion hold a great deal of potential, and have for quite some time. Though they offer up to five times more energy per weight, one major roadblock has been a far shorter lifespan. An international team of scientists believes it has now overcome this hurdle through a new type of bonding architecture, resulting in an unprecedented battery charge/discharge efficiency in a lithium-sulfur battery that could keep a smartphone running for days.

"Ironically, a main challenge to mass adoption of lithium-sulfur batteries until now, has been that the storage capacity of sulfur electrode is so large that it cannot manage the resultant stress," Monash University's Dr Mahdokht Shaibani, study lead author, explains to New Atlas. "Instead it breaks apart, in the same way we might when placed under stress."

Shaibani tells us this is because the stress leads to the distortion of key components, namely the carbon matrix responsible for passing electrons to the insulating sulfur, and the polymer binder that holds those two materials together. The resulting breakdown of this connection causes a rapid deterioration in the battery's performance.

So Shaibani and a team of international collaborators started looking at new ways of holding it all together. Rather than using the binding material to form a dense network with little room to spare, she decided to "give the sulfur particles some space to breath!"

The new battery relies on a traditional binding agent, but processed in a different way to form ultra-strong bridging bonds between the carbon matrix and sulfur particles that allow for extra space as the battery expands during charging. These bonds can be seen in figure b below.

Scientists have used a new type of bond to hold key components of lithium-sulfur batteries together during charging
Scientists have used a new type of bond to hold key components of lithium-sulfur batteries together during charging

"In other words, I created a web-like network where only a minimum amount of binder is in place between the neighboring particles, leaving increased space for accommodating the changes in the structure and the resultant stress," Shaibani says.

The team's experiments with its new lithium-sulfur battery have produced some promising signs. In testing over more than 200 cycles, the battery exhibited a charge/discharge efficiency of more than 99 percent, "which to the best of our knowledge is unprecedented for such high capacity electrodes," says Shaibani.

The researchers say the battery could power a smartphone for five continuous days or enable an electric vehicle to drive more than 1,000 km without recharging. They are poised to trial the battery further over the coming year, both in electric cars and as a storage option for solar power. They have also filed a patent for the technology, which in addition to improved performance promises lower cost and less environmental impact than traditional lithium-ion batteries.

"This approach not only favors high performance metrics and long cycle life, but is also simple and extremely low-cost to manufacture, using water-based processes, and can lead to significant reductions in environmentally hazardous waste," says study co-author Matthew Hill.

The team has published its research in the journal Science Advances.

Source: Monash University

14 comments
Mzungu_Mkubwa
Unless the cost is significantly lower, 200 recharge cycles is still too short of a lifespan. Don't want to have to change out my car battery twice a year... Also no mention of other important performance metrics such as charge time and discharge rates...
KenMills
great new battery tech but will we see products in our lifetime? lots of new breakthroughs but we are still using Lion.
Gerry W
at 1000 km per cycle you could get 200,000 km out of this battery. Hardly replacement twice a year unless you are an astronaut.
BlueOak
They got a lousy tiny $2.5 million investment. Something is missing here. If this - 400% capacity of today’s batteries technology is both economic and durable, where is real investment in their solution?
mmmbo
Mzungu_Mkubwa, you misunderstand the report. It says that after more than 200 cycles, the battery's charge/discharge efficiency remained at 99%. As far as I know, this performance is PHENOMENAL compared to current technologies.
Signguy
I'll believe it when it's on the market and in our devices.
guzmanchinky
We will see leaps and bounds with battery tech, just like we did with early computer tech between 1990 and today.
neoneuron
BlueOak - It's all about money and oil. :( - - - Nothing good for the common good. Technology seems to be vexed on privacy and profit
Ajay Narayan
This is a Wonderful news. The world must get together is such cases to relieve the dependence on fossil fuel and promote to excel such discoveries. We have to save our planet form climate change.
ljaques
Congrats on your successes so far, Dr. Shaibani and crew! We look forward to safer, denser, and longer lived cells soon. Best of luck in your total success.