Chemists develop potentially cheaper battery for grid energy storage
A more cost-effective rechargeable zinc-ion battery has been developed by chemists at the University of Waterloo, Canada. Since their manufacture does not require special conditions, low humidity or the use of flammable materials, this could produce batteries that are half the price of lithium-ion equivalents. The new battery uses non-toxic, non-flammable materials and a pH-neutral, water-based salt and could be of interest to manufacturers as the global market for energy storage is expected to grow to $25bn in the next 10 years.

Chemists at the University of Waterloo have developed a rechargeable zinc-ion battery that is said to cost half the price of lithium-ion batteries because its fabrication does not require special conditions, such as low humidity or the use of flammable materials.

This could be especially attractive to manufacturers as the global market for energy storage is expected to grow to $25billion in the next 10 years. It could also enable communities to shift away from traditional power plants into renewable solar and wind energy production.

Dipan Kundu, one of the researchers, said: "Grid storage needs a different kind of battery and that's given us license to look into different materials."

The researchers claim the battery uses safe, non-flammable, non-toxic materials and a pH-neutral, water-based salt. It consists of a water-based electrolyte, a pillared vanadium oxide positive electrode and a metallic zinc negative electrode. The battery generates electricity through intercalation, where positively-charged zinc ions are oxidised from the zinc metal negative electrode, travel through the electrolyte and insert between the layers of vanadium oxide nanosheets in the positive electrode.

Water in the electrolyte not only facilitates the movement of zinc ions, it also swells the space between the sheets, giving the zinc just enough room to enter and leave the positive structure as the battery cycles. The electrode material's nanoscale dimensions and the battery's high-conductivity aqueous electrolyte are said to improve its cycling life and response times, providing more than 1000 cycles with 80% capacity retention and an estimated energy density of 450watt-hours/litre.