Next-generation lithium-ion batteries that hold more than 3 times the charge that current batteries do and can recharge in around 10 minutes are now within reach. The new design, created by researchers at the University of Southern California (USC), may be commercially available within only 2-3 years according to those involved.
The design is based on replacing the currently used graphite anodes with porous silicon nanoparticles. This follows work done by the same researchers last year using silicon nanowires. The nanowire version actually lasts much longer (2000 recharge cycles) than the current nanoparticle version (200 recharge cycles) and conventional graphite-based designs (500 recharge cycles). But the researchers are confident that the lifespan of the nanoparticle design can be greatly improved in the near future. The problem with nanowires is just that they are relatively hard to mass manufacture, while silicon nanoparticles are readily available.
The impressive charge capacity and recharge rate could be very useful for many slow-charging batteries currently in use, such as those used in electric and hybrid cars, laptops, cell phones, etc.
“Researchers have long attempted to use silicon, which is cheap and has a high potential capacity, in battery anodes. (Anodes are where current flows into a battery, while cathodes are where current flows out.) The problem has been that previous silicon anode designs, which were basically tiny plates of the material, broke down from repeated swelling and shrinking during charging/discharging cycles and quickly became useless,” the University of Southern California press release states.
So, last year, the researchers began experimenting with silicon nanowires, with their small size and their porous nature offering some resistance to the damage caused by swelling. “The tiny pores on the nanowires allowed the silicon to expand and contract without breaking while simultaneously increasing the surface area — which in turn allows lithium ions to diffuse in and out of the battery more quickly, improving performance.”
The researchers are also working on the development of a new cathode material to pair with the silicon nanowires and nanoparticles, potentially creating an entirely new battery design.
The new research was published in Nano Research.
Image Credit: Silicon via Wikimedia Commons