Researchers say substituting lithium in rechargeable batteries with a more abundant material like potassium could help us develop a more sustainable energy source.
Fears about the scarcity of lithium and other materials necessary in the now-ubiquitous lithium-ion batteries have just driven many researchers to look for substitutes, such as sodium and potassium.
Professor Shinichi Komaba from Tokyo University of Science, Japan, and his team have worked for over a decade on this topic. In his latest review article, he extensively discusses his findings on the recent advances, promises, and limitations of potassium-ion batteries.
Our everyday lives would be greatly different without rechargeable batteries. Owing to their low-cost, recyclable technology, these batteries are used in most portable electronic devices, electric and hybrid vehicles, and renewable power generation systems. They offer an elegant solution to the world’s growing energy demands. Moreover, rechargeable batteries are an essential tool in systems that harvest renewable energy, such as the wind and sunlight, because these sources can fluctuate greatly with the weather.
Rechargeable batteries allow us to store the generated electricity and dispatch it on demand. Thus, it is no surprise that researchers globally have been focused on improving rechargeable batteries as a step towards developing sustainable energy resources.
Therefore, a team of scientists at Tokyo University of Science led by Professor Shinichi Komaba decided focus on replacing the exhaustible element lithium with better alternatives like sodium and potassium. Sodium and potassium are in the same alkali metal group in the periodic table of elements, and their chemical natures are, therefore, quite similar.
Unlike lithium, these elements are widely abundant on Earth, and using them to develop high-performance rechargeable batteries would be a breakthrough towards creating a more sustainable society.
In 2014, Komaba, along with Professor M Stanley Whittingham, who won the Nobel Prize in Chemistry in 2019, analysed the current state of development of sodium-ion batteries and published his assessments as a review. This became a highly cited study, with over 2,000 citations only in the past 5 years.
Komaba and his team then explored other plausible alternative to LIBs, potassium-ion batteries (KIBs), which have slowly become the focus of extensive research since 2015 after certain pioneering studies (eg: a study published in Nature Materials in 2012), some of which were carried out by Komaba’s group.
The use of potassium in batteries is promising because they show comparable (or even better) performance to LIBs. What’s more, the materials necessary to build KIBs are all non-toxic and much more abundant than those required for LIBs. Prof Komaba states, “By studying new materials for applications in lithium-, sodium-, potassium-ion batteries, we wanted to develop an energy-efficient and environment-friendly technology.”