Materials science: New design for sustainable zinc batteries

A new design that can improve the performance and cost of producing aqueous zinc-ion batteries is presented in Nature Sustainability. These findings suggest the feasibility of developing practical zinc-ion batteries that combine safety, performance and sustainability, highlighting their potential as replacements for traditional lithium-ion batteries used inportable electronics and electric vehicles.

Interest in the use of aqueous zinc-ion batteries as a more sustainable alternative to lithium-ion batteries for portable electronics and electric vehicles has risen, because zinc is safer, more cost-effective and environmentally compatible than lithium. However, challenges exist with regard to the use of aqueous electrolytes — the liquid within a battery that conducts ions — in zinc-ion batteries. These include the risk of irregular zinc deposition, hydrogen gas production and electrode corrosion, all of which can lead to fast performance degradation.

Quan-Hong Yang and colleagues report the design of a new type of electrolyte composed of a hydrated zinc salt, in which the intrinsic, small amount of water plays a critical role in addressing safety and technical issues associated with aqueous zinc-ion batteries, while also being non-flammable. The authors additionally detail the cost competitive nature of their electrolyte design compared with electrolytes that are normally used in zinc-ion batteries. Furthermore, the battery demonstrated here shows excellent performance not only at room temperature but also within a temperature range from −30 to 40 oC.

In an associated News & Views article, Florencio Santos and Antonio Fernández Romero emphasize that although performance should be further optimized, this work has “tackled several critical issues of zinc batteries by using a cheap and environmentally friendly electrolyte.” They go on to conclude that “building on the contribution here, it is possible to produce and implement reliable and affordable batteries to aid the transition to a sustainable future.”