Lithium-ion batteries invaded portable, and then energy-storage space, and have mostly seen off other new-comers. However, this is not to say that they are perfect. They have a concerning habit of catching fire occasionally, if they overheat. And they also contain the rare element cobalt, which has unwelcome social, environmental, and economic consequences. On October 20, 2023 University of Tokyo reported a ‘cobalt-free lithium-ion battery for greener power’.
High Capacity, Reliable Cobalt-Free Lithium-Ion Battery
Researchers at University of Tokyo set themselves a goal to remove cobalt from the lithium-ion battery equation. They came up with a solution that eliminates cobalt, and can survive a large number of recharges. But it also ‘outperforms state-of-the-art battery chemistry in some ways’, they say, which makes it well worth exploring further.
The University of Tokyo explains how markets generally overlook lithium-ion battery negatives. That’s because they are among the most energy-dense portable power sources available. Although their users still complain about the need to recharge them so often, and wish they were more dense and more powerful.
The Drive Towards Cobalt-Free Energy Storage
“There are many reasons we want to transition away from using cobalt” explains Prof Yamada at Tokyo University. “For us, the challenge is a technical one, and so we used a novel combination of elements in the electrodes.” Lithium, nickel, manganese, silicon and oxygen all contributed to the mix that brought success, plus this unexpected bonus for their work:
- Their prototype battery had 60% greater density than traditional lithium-ion.
- It delivered 4.4 volts compared to 3.32 to 3.7, and should also have a longer life.
- The prototype battery still retained 80% of its capacity after 1,000 charging cycles.
We are still struggling to perfect our model, Prof Yamada admits. We have a way to go, he concedes, but we are delighted with the results so far.
More Information
Cobalt Mining Still a Stain on Batteries
EV Makers Pushing Hard for Ethical Cobalt
Preview Image: Greater Density Without Cobalt
