A US startup says it can produce cobalt-free battery cells using lithium ion chemisty without reducing the performance of electric vehicles.
TexPower in Austin is using research from the Cockrell School of Engineering at The University of Texas at Austin. The team developed a cathode that is 89 percent nickel with manganese and aluminium making up the other key elements (NMA) without reducing the lifetime or energy density and so is comparable to the current NMC (nickel-manganese- cobalt) or NCA (nickel-cobalt-aluminium cells.
This is particularly relevant as electric vehicle maker Tesla has been working on cobalt-free batteries, applying for several patents on the technology. It is expected to make a key announcement on Sep 22nd at its ‘Battery Day’ on the technology. TexPower is starting off with a US government grant for $200,000 to investigate the use of the material for electric vehicle batteries.
Cobalt costs around $28,500 per ton, more than the nickel, manganese and aluminium combined, and can be up to a third of a lithium-ion battery cathode. The sources of cobalt are also challenging: UN REPORT DRIVES COBALT-FREE AND SILICON BATTERY TECH
Various projects across Europe are looking at how to produce cobalt-free battery cells, particularly for EVs: SVOLT PLANS €2bn EUROPEAN FACTORY FOR STACKING BATTERY PACKS
“Cobalt is the least abundant and most expensive component in battery cathodes and we are completely eliminating it,” said Arumugam Manthiram, a professor in the Walker Department of Mechanical Engineering, director of the Texas Materials Institute and founder of TexPower.
The NMA cathode is built with a technique that ensures the ions of the various metals remained evenly distributed across the crystal structure. Keeping the ions evenly distributed avoids the loss in performance. The researchers built a half coin cell with a lithium anode and a full pouch cell with an graphite anode to test the cathode material. The cobalt-free battery pouch cell showed that the NMA cathode maintained its charge over 1000 cycles better than NMC and NCA cells.
“Our goal is to use only abundant and affordable metals to replace cobalt while maintaining the performance and safety,” said researcher Wangda Li, “and to leverage industrial synthesis processes that are immediately scalable.”
“We are increasing the energy density and lowering the cost without sacrificing cycle life,” said Manthiram. “This means longer driving distances for electric vehicles and better battery life for laptops and cellphones.”