In a move that could spell the end of lithium batteries - a mineral which is a finite resource - scientists have created a new battery which is powered by sodium. They believe that this will create a new era for battery storage, especially in a world increasingly driven by renewable resources.

Lithium has long been used for rechargeable batteries, but it is costly to mine and negatively impacts the environment as well as being limited in its supply. It's used for electric car batteries, but there has been a growing need to find an alternative.

Sodium is both abundant and cheap to produce, but sodium batteries haven't previously been a success because of difficulties in preventing the sodium ions from sticking to the negative electrodes in each battery cell.

With lithium batteries, the ions pass during discharge from the negative to the positive electrode. This action generates the energy that provides battery power. Now the research team behind the sodium innovation at Purdue University have been able to create a new version that uses sodium powder. This fixes the ion problem and means that the new wave of batteries can discharge correctly and recharge fully.

The sodium powder is made using an ultrasound. This melts chunks of sodium into purple liquid, which then cools to make a powder. To ensure that the particles are dispersed evenly, the powder is suspended in an alkane liquid called a hexane. 

If developed successfully, sodium-ion batteries would be heavier than the existing lithium technology, but they could also be used to store wind and solar energy at a lesser cost.

The development is another step forward towards reliable renewable energy storage, and the research team behind the innovation are hoping to move towards a commercial development phase.