The history of batteries started a long time ago, in 1786 to be precise, when an Italian doctor and scientist named Galvani tried to dissect a frog using two different metal tools (iron and bronze). The frog’s leg started to dance and Galvani promptly declared he had discovered “animal electricity”! A few years later (in 1800) another Italian named Volta stacked copper and zinc plates, closed the circuit and really discovered the principle of the battery. He called his invention “pila” which is still the common name for a primary battery today.
Throughout the centuries and still today, primary batteries were constantly redesigned, improved and miniaturized, and zinc was always the main constituent, associated with copper, manganese, silver and even air! Did you know 25% of all alkaline batteries in the world are “EverZinc inside”?
But a primary battery that could not be recharged was not enough for the world and soon enough at the end of the 19th century the first zinc rechargeable battery was invented, based on liquid zinc bromide. And in 1901, it was zinc-nickel’s turn, with Thomas Edison holding one of the first patents on it.
However, in the second half of the 20th century zinc rechargeable batteries would be increasingly surpassed by other, higher performance systems such as lead-acid (car batteries, stationary storage), nickel-cadmium (power tools, toys), nickel-metal hydride (cellphones, toys, hybrid electric vehicles) and of course the ubiquitous lithium-ion (portable electronics, electric vehicles, storage).
So why is zinc staging a comeback in the rechargeable battery? Why does it have such a promising future in the electrical energy storage?
For one, the unavoidable energy transition away from fossil energy will require much more electricity transportation and storage. This is true for mobility (to carry people and goods) but mostly for stationary applications (to store renewable energy from sun, wind and water). This will lead to an explosion in the demand of batteries in the coming decades.
Zinc being abundant, cheap, safe, recyclable and applicable in many different compositions and shapes, will be the ideal compromise and much awaited solution for large storage and regular release of energy, such as off-grid electricity storage systems (villages, GPS, telecom), data centers, public transportation, individual or industrial mobility.