In 2007, the same team led by materials science professor Yi Cui, developed silicon nanowire anode that could hold 10 times as much charge as conventional lithium-ion batteries.
By combining the new cathode with the previously developed silicon anode, the team created a battery with an initial discharge of 630 watt-hours per kilogram of active ingredients.
This represents an approximately 80 percent increase in the energy density over commercially available lithium-ion batteries, according to Stanford’s Cui, who was a coauthor of a paper describing the work published last month in Nano Letters.
The new battery combines a Li2S/mesoporous carbon composite cathode and a silicon nanowire anode.This new battery yields a theoretical specific energy of 1,550 Wh kg-1—four times that of the theoretical specific energy of existing lithium-ion batteries based on LiCoO2 cathodes and graphite anodes (~410 Wh kg-1). The team experimentally realized an initial discharge specific energy of 630 Wh kg-1 based on the mass of the active electrode materials.
This new technology is apparently safer, and it currently achieves 80 percent more capacity than lithium-ion batteries, but it’s nowhere near commercial launch with just 40 to 50 charge cycles.
To be competitive with lithium-ion batteries, the batteries developed at Stanford would have to operate for 300 to 500 charge cycles for consumer electronics applications and as many as 1,000 cycles for vehicle use.