Scientists in Japan are working on new types of batteries that don't need lithium like your smartphone battery. These new batteries will use sodium, one of the most common materials on the planet rather than rare lithium – and they'll be up to seven times more efficient than conventional batteries.
Research into sodium-ion batteries has been going on since the eighties in an attempt to find a cheaper alternative to lithium. By using salt, the sixth most common element on the planet, batteries can be made for cheaper and we won't need to worry about lithium running out. With battery-powered cars on the increase it's only a matter of time before lithium becomes too rare and expensive.
The problem, until recently, was sodium meant larger ions which require more power to keep energy flowing. The use of carbon has led to a battery being created that not only has a capacity up to seven times more than lithium but can also survive discharging and recharging many times. Another issue came from maintaing a liquid state for the sodium, which has also been overcome.
Commercialising the batteries is expected to begin for smartphones, cars and more in the next five to 10 years.