Mullen Technologies has surprisingly announced that it will equip its electric cars with lithium-sulfur batteries. For this, the Californian startup is cooperating with the company NexTech Batteries. Mullen plans to produce more than 100,000 vehicles with lithium-sulfur pouch cells from NexTech within five years.
According to Mullen, NexTech’s lithium-sulfur batteries are “expected to be 60 per cent lighter” and also significantly increase vehicle range. In addition, the company anticipates significantly lower costs and a more sustainable product because sulfur is more readily available than rare earth metals, Mullen says. The startup had announced the MX-05 electric SUV in October 2020, which is expected to have a range of more than 520 kilometres with a base price of $55,000.
“This technology allows Mullen to potentially be below $90/kWh at a pack level, greatly reducing cost to consumers,” said Frank McMahon, CTO of Mullen. “The low carbon footprint, high specific energy density and much lower cost to the consumer will make Mullen extremely competitive in this market segment.” $90 per kilowatt-hour currently equates to €75/kWh.
Research on lithium-sulfur batteries has been ongoing for many years, as these cells promise very high energy density – which Mullen alludes to. However, only relatively few charging cycles are usually possible with Li-S cells – too few for commercial use in electric cars. In Germany, various Fraunhofer institutes, among others, have been researching the technology. The British company Oxis Energy is also considered a specialist for Li-S cells, but so far its customers are primarily in the aviation industry.
How exactly NexTech has solved the challenge with the charging cycles and what charging performance would be possible with such a battery is not clear from the announcement. Bill Burger, CEO and founder of NexTech, as well as his CTO Fabio Albano, only comment in general terms about their product. “Electric mobility is at the heart of NexTech’s purpose, and making batteries affordable, sustainable and safe are some of the most important technological challenges needing to be solved. Better EVs and higher energy density are clearly key to achieving these goals,” Burger said.
NexTech sources the sulfur from “sustainable sources,” Mullen writes, but specifies that it is a recycling process of byproducts from oil refining. All materials used by NexTech should be recyclable, available and cost-effective, the company says.
Mullen founder and CEO David Michery indicated that the MX-05 electric SUV should begin shipping in 2023 with NexTech’s current cells, with parallel work on introducing solid-state batteries. “This will keep Mullen as a leader in this space for generations of vehicles,” Michery said. In January, Mullen Technologies had reported a potential major order for its MX-05 electric SUV.