Anode built with titanium nobium oxide enables safer operation with double the energy density, says Toshiba
Toshiba Corporation has announced the development of a next-generation SCiB™, which it says uses a new material to double the capacity of the battery anode.
The company’s existing SCiB range, first launched in 2008, is defined by its use of oxide-based materials (Lithium Titanium Oxide), which prevent thermal runaway resulting from short circuiting. SCiB cells have been used in infrastructure, automobiles, buses, railroad cars, elevators and power plants.
However, in researching new materials it has designed a new battery which “offers high-energy density and the ultra-rapid recharging required for automotive applications.” Using titanium niobium oxide in constructing the battery anode, it says the material doubles the lithium storage capacity by volume compared with graphite-based anodes.
In practice, it says this can offer a compact EV a range of 320km after only six minutes of “ultra-rapid recharging” – around three times the distance possible with current lithium-ion batteries. (In its assessment, the EV is a 32 kWh compact car with fuel economy tested under Japan’s JC08 test cycle, although it is unclear what level of charge power is used in “ultra-rapid charging”. Given the short time and quoted battery capacity however, ElecTrans would presume a 350kW installation).
Titanium niobium oxide anode is also less likely to encounter lithium metal deposition – i.e. dendrite formation – during ultra-rapid recharging or recharging in cold conditions, making it a sound choice for EV applications.
So far, testing of a 50Ah prototype battery shows success in “long life cycle, low-temperature operation, excellent safety and rapid recharging characteristics of the current SCiB”, although exactly how long and how low was not made explicit.
Toshiba said that energy density by volume of battery is also twice that of the current SCiB range.
The prototype cell maintained over 90% of its initial capacity after being put through 5,000 charge/discharge cycles, and ultra-rapid recharging can be done in cold conditions, with temperatures as low as minus 10°C, in only ten minutes – all of which bode well for automotive applications.
“We are very excited by the potential of the new titanium niobium oxide anode and the next-generation SCiB,” commented Toshiba’s Corporate Research & Development Centre director, Dr. Osamu Hori. “Rather than an incremental improvement, this is a game changing advance that will make a significant difference to the range and performance of EV. We will continue to improve the battery’s performance and aim to put the next-generation SCiB into practical application in fiscal year 2019.”
Even with commercialisation in 2019, the new cells could make their way into the many of much-vaunted 300-mile capable EVs promised by major automakers for 2020 and beyond. Whether they can compete on price is another question, but Toshiba’s announcement seems a significant development in the battery market.