A cobalt-free high-energy lithium-ion battery is possible, according to the University of Texas at Austin.
The cathode is made from 89% nickel, then manganese and aluminium, part of a group of alloys dubbed NMAs.
They were compared with high-nickel (both also 89%) cobalt-inclusive alloys from groups called nickel-manganese-cobalt (NMC) and nickel-cobalt-aluminium (NCA), described as “the cathode materials of choice for next‐generation high‐energy lithium‐ion batteries”, by the Austin researchers in their Advanced Materials paper ‘High‐nickel NMA: a cobalt‐free alternative to NMC and NCA cathodes for lithium‐ion batteries’.
In test cells with graphite anodes, the NMA beat NMC and NCA after 1,000 deep cycles (but not NMCAM, nor a commercial cathode).
“Eliminating cobalt usually slows down the kinetic response of a battery and leads to lower rate capability,” according to the university. “However, the researchers said they’ve overcome the poor rate capability, and short cycle life, through finding an optimal combination of metals and ensuring an even distribution of their ions.”