Lithium-ion (Li-ion) batteries are the storage technology of choice for applications from electric cars to smartphones. The next step for these batteries looks to be saving power in the home. Tesla unveiled the Power Wall earlier this year to do just that, however the $3000 price tag for the pack plus the cost of installing it puts it out of reach for most consumers. To make larger-scale energy storage more accessible, Maksym Kovalenko and colleagues wanted to develop an affordable alternative to the Li-ion battery.
The researchers started with magnesium as the battery’s safe, inexpensive and high-energy density anode material and paired it with pyrite, which is made of iron and sulphur, as the cathode. The electrolyte contains sodium and magnesium ions.
According to the researchers, testing showed that the resulting device’s energy density was close to that of Li-ion batteries, and it could get an additional two-to-three fold boost with further development of magnesium electrolytes. Kovalenko team also say that because it is made with low-cost materials, it could one day be scaled-up to help support grid-scale energy storage.