New electrolyte for cheaper, less toxic batteries

Researchers have developed an electrolyte that can be used to usher in a new generation of more efficient and inexpensive magnesium-sulphur batteries.
With magnesium, higher storage densities could be achieved than with lithium. Moreover, magnesium is abundant in nature, it is non-toxic, and does not degrade in air, researchers said.
In many electrical devices, lithium-ion and metal-hydride batteries are applied for energy storage.
Scientists are studying alternatives to these established battery systems in order to enhance the safety, cost efficiency, sustainability, and performance of future devices.
A research team at the Helmholtz Institute Ulm (HIU), headed by Maximilian Fichtner and Zhirong Zhao-Karger has now presented a new promising electrolyte, which might allow for the development of an entirely new generation of batteries.

The new electrolyte possesses an unprecedented electrochemical stability window and a very high efficiency.

In addition, the electrolyte can be used in various solvents and at high concentrations.
Moreover, the electrolyte is chemically compatible with a sulphur cathode, which can be discharged at a voltage close to the theoretical value. Another advantage is the very simple production of the electrolyte.
"Two commercially available standard chemicals, a magnesium amide and aluminium chloride, are applied. They are added to the solvent desired and subjected to stirring. This simple mixture can then be used directly as an electrolyte in the battery," Fichtner said.

Magnesium-based battery cells are presently considered an attractive option to replace lithium in batteries. In principle, magnesium allows higher storage densities to be reached than lithium.
The research was published in the journal Advanced Energy Materials.