University of Birmingham scientists are paving the way to swap the lithium in lithium-ion 

batteries with sodium, according to research published in the Journal of the American 

Chemical Society.

Lithium-ion batteries (LIB) are rechargeable and are widely used in laptops, mobile phones 

and in hybrid and fully electric vehicles. The electric vehicle is a crucial technology for fight

ing pollution in cities and realising an era of clean sustainable transport.

However lithium is expensive and resources are unevenly distributed across the planet. Lar

ge amounts of drinking water are used in lithium extraction and extraction techniques are 

becoming more energy intensive as lithium demand rises – an 'own goal' in terms of 

sustainability.

With the ever increasing demand for electric cars, the need for reliable rechargeable batter

ies is rising dramatically, so there is keen interest in finding a charge carrier other than lithiu

m that is cheap and easily accessible.

Sodium is inexpensive and can be found in seawater so is virtually limitless. 

However, sodium is a larger ion than lithium, so it is not possible to simply "swap" it for lithium 

in current technologies. For example, unlike lithium, sodium will not fit between the carbon 

layers of the ubiquitous LIB anode, graphite.

The scientists needed to find new materials to act as battery components for sodium-ion 

batteries that will compete with lithium for capacity, speed of charge, energy and power 

density.

Running quantum mechanical models on supercomputers, Dr. Andrew Morris's team from 

the University of Birmingham's Department of Metallurgy and Materials was able to predict 

what happens when sodium is inserted into phosphorus.