137-year-old super battery replaces lithium batteries?

By Gottlieb Rössler 28 April 2023

137-year-old super battery replaces lithium batteries?

Of all things, a battery technology more than 137 years old is currently revolutionising energy storage.

We are talking about the redox flow battery, and in particular the zinc-bromine battery.¹ It is in fact probably the most promising competing technology to the lithium battery, and it is not only ready for the market already, but is even available both on a large scale for industry and on a small scale for private individuals.²˒³

Among the market leaders there are in fact several German companies. That will surely surprise many, as the technology is really relatively unknown.⁴ The battery is non-flammable, can easily be recycled and lasts an incredibly long time. Even after 10,000–20,000 cycles, i.e. after more than a decade of continuous use, the full 100% storage capacity is still available.

But not all flow batteries are the same. In fact, there are huge differences and many different approaches in cell chemistry alone. What is clear, however, is that the lithium battery will be replaced in many areas! But what really makes financial sense?

Let’s take a closer look. In terms of certain specifications, the lithium battery is simply unbeatable. Particularly noteworthy is its excellent energy density, which, depending on the design, beats the energy density of other batteries by a factor of 4–7.⁵

That makes it indispensable in all areas in which gravimetric energy density, i.e. energy density in relation to the mass or weight of the battery, plays an overriding role.⁵ Particularly noteworthy here, of course, is the transport sector with e-bikes, e-scooters and electric cars. But technical devices also depend on compact, light batteries. In addition, the lithium battery impresses with its high cycle stability and the long service life that goes with it.

Lithium batteries, for example, often have a guaranteed capacity of 80% after more than 10,000 charging cycles.⁵ But besides the fact that lithium mining is repeatedly criticised for environmental problems, there is also an economic reason why we should replace lithium batteries as quickly as possible in all areas where this is possible: the lithium battery is incredibly expensive. In some sectors this is actually slowing down the energy transition considerably.⁶