Potassium Battery Breakthrough A Potential Game-Changer

The use of lithium batteries has been growing around the world, partly to power the growing fleet of electric cars needed as petrol and diesel vehicles are phased out, but also in electronic items such as laptops and mobile phones. However, they may be about to get overtaken in some applications by potassium-ion batteries.

Potassium is more plentiful than lithium, but until now lithium-ion batteries have had the edge due to the fact that potassium devices require a substance called Prussian White mixed with carbon in cathodes. Doing this makes them more complex and therefore harder to make.

A Big Potassium Breakthrough

However, researchers at the University of Glasgow’s School of Chemistry and the Helmholtz Institute in the German city of Ulm have found an alternative cathode made from a combination of chromium and selenium that works extremely well.

The cathode needed only ten per cent carbon to reach a capacity of 125 mAh/g, just below its theoretical capacity of 127 mAh/g.

This should make it possible to produce potassium-ion batteries that work just as well as lithium, with the benefit that potassium oxide suppliers can access a far more abundant source of the material than lithium, which is comparatively scarce and harder to obtain.

Lead author of the study and head of the Head of the Glasgow ElectroChemistry on Solids (GECOS) group at Glasgow’s School of Chemistry Dr Alexey Ganin commented: “Potassium is a much more abundant material, and potassium-ion batteries have a lot of potential as an alternative method of storing and delivering large amounts electricity.“

Potassium batteries are not there yet, however, with Dr Ganin explaining: “Designer lithium-ion battery electrolytes can be bought off the shelf, but further work is required to refine the performance of electrolytes for potassium-ion batteries.”

However, this certainly creates the prospect that potassium has a major new role to play. That in turn could alter the focus of lithium.

Why Lithium Will Still Matter

What it will not do, however, is render it obsolete, with Dr Ganin explaining: “Adopting potassium-ion batteries for stationary storage purposes could help free up lithium resources for use in more energy-intensive mobile applications in the future.”

What this means is that major developments in lithium battery technology and the development of a nascent lithium mining and refining sector in the UK will not go to waste.

In the British case, last month saw the launch of the first lithium production facility of its kind in Cornwall. As Cornwall Live reported, the Cornish Lithium demonstration plant near St Austell shows how lithium hydroxide can be produced from granite extracted from a former China clay pit.

Cornish Lithium aims to be producing 10,000 tonnes of lithium a year by 2027, with chief executive Jeremy Wrathall commenting: “We’re home to the largest lithium resource in Europe with enough beneath our feet in Cornwall to supply over half of what the electric vehicle industry needs.”

With Similar ambitions at the opposite end of England being expressed by Weardale Lithium in County Durham, the UK’s own domestic supply could be up and running very soon, although there will still need to be significant importation of the substance unless further resources can be found and exploited in the UK, possibly from seawater.

The Global Lithium Situation After The Arkansas Discovery

Elsewhere, however, very large deposits have been found with great regularity in recent years, with the US now in a very good position thanks to the discovery of a rich deposit of lithium in Arkansas estimated to amount to between five and 19 million tonnes, which could mean it meets projected global demand for car batteries nine times over.

Of course, that does not mean the whole world will simply rely on one deposit in the US. But with the UK soon to start its own production and other deposits being found around the globe, plus refineries being built around the world – including the Tees Valley – the concerning prospect a few years ago of China dominating the lithium industry has vanished.

That does not mean there will be no geopolitical issues surrounding lithium supplies, but if the new development in potassium batteries made by the experts in Glasgow and Ulm can be progressed to the point of making potassium batteries an alternative to lithium in most cases, the need for lithium, while still substantial, will not be as overwhelming.

Moreover, the UK, given it will then have access to both materials in substantial quantity and be able to meet more of its lithium needs domestically, will be in a better position, all the while keeping mineral refineries very busy.