Efficient energy storage is one of the main issues holding back large scale renewable energy projects. On a more personal note, that's also the reason why we still have to charge our phones more or less every day. These batteries need to be charged very carefully since the internal components are flammable. Scientists at the Joint Center for Energy Storage Research are looking for a better solution and have been making some recent breakthroughs.
Their research is focusing on magnesium-based batteries rather than traditional lithium-ion technologies. Preliminary findings show that these new "Magnesium Intercalation System" batteries are safer and have a higher energy density than lithium.
The Berkeley Lab scientists who are doing the research point to the way the electrolyte behaves as a key differentiating factor. Traditional batteries use a liquid electrolyte to transport the charge from anode to cathode. Damages to the outer casing or overcharging can cause this electrolyte to heat up and catch fire.
When designing the magnesium battery, they couldn't find a high performance electrolyte that was compatible, so the Department of Energy team just designed their own.
The new solid-state electrolyte is formed from magnesium scandium selenide spinel and allows the magnesium ions to move at an "unprecedented speed" through the battery. Teams at MIT and Argonne National Laboratory also provided assistance to the team.