Zinc-air batteries are lighter than Lithium-Ion, cheaper to produce, non-toxic, and environmentally friendly, but currently suffer from a major shortcoming — their charge depletes far quicker than competing technologies. Eos Energy, a Pennsylvania startup, claims to have overcome this problem by developing a new electrolyte — the conductive chemical within the battery. Because of these developments, the tech could be seen in wide use outside of hearing aid batteries, where it's currently most commonly found.

Unlike most zinc-air batteries in use today, Eos's new tech can also be recharged, which has led the firm to target grander things. By next year, it hopes to be able to produce megawatt batteries for use by electricity companies to smooth power supply, and is also looking at the growing electric vehicle market. The challenge the company has set itself is high — while it's currently been able to produce a 0.33 kW model that's recharged 2,700 times without any sign of degradation, it's targeting 10,000 cycles for the large production models — which should last up to 30 years. Whether it can compete in lifespan as Lithium-Ion evolves is another story.