'Dream' smartphone battery can be fully charged in under a minute
A team of scientists at Stanford University have developed what they call a "dream battery", using aluminium rather than lithium.
Other than being cheap, non-flammable, bendable, long-life, and environmentally friendly, the battery can be fully charged within a minute to liberate phone users from the constant search for a power socket.
Unfortunately, there is still one hurdle to clear before the battery reaches market: voltage. At present, the battery produces only about half the voltage of a regular lithium battery.
But the problem could be solved, said Hongjie Dai, professor of chemistry at Stanford and key author of the paper published online by journal Nature this week.
“Improving the cathode material could eventually increase the voltage and energy density,” he said in a Stanford press release.
“Otherwise, our battery has everything else you'd dream that a battery should have: inexpensive electrodes, good safety, high-speed charging, flexibility and long cycle life … It's quite exciting."
Aluminium has long been a dream material for battery production due to its low cost, low flammability and high-charge storage capacity.
But all previous attempts to develop a commercially viable aluminium battery have failed, mainly because of the challenge of finding an appropriate material for the cathode, the passively charged electrode in the battery to draw electrons from the negatively charged anode made of aluminium.
“People have tried different kinds of materials for the cathode," Dai said.
"We accidentally discovered that a simple solution is to use graphite, which is basically carbon. In our study, we identified a few types of graphite material that give us very good performance."
The new battery was safer than most batteries in use today, which can cause environmental hazards, especially alkaline batteries, or catch on fire, which is a risk with lithium-ion batteries.
Last month, a woman riding the MTR near Fo Tan station in Hong Kong's New Territories was shocked to find that her Samsung Galaxy Note II device was on fire. She threw the burning device through the train's open doors at it pulled into a station.
Police later said the fire had been caused by a faulty battery.
In a demonstration video the Stanford researchers drilled through the new battery pack and it remained working without any trouble.
The Stanford battery is also long lasting. In lab tests it was able to withstand more than 7,500 circles without any loss of capacity, while a typical lithium battery lasts only about 1,000 circles.