Zinc air battery maker looks beyond lithium

Start-up ReVolt Technology is developing rechargeable zinc air batteries, a technology it says promises longer runtime for consumer electronics and plug-in vehicles.

The Switzerland-based company, which was spun out of a Norwegian research institute five years ago, anticipates commercializing a rechargeable coin-size batteries next year. But the technology has the potential to be a cheaper and more energy-dense alternative to lithium ion batteries in consumer electronics, grid storage, and transportation, according to CEO James McDougall.

The components of ReVolt's current rechargeable battery technology include an air electrode, an interface below it in blue, and a zinc electrode.

(Credit: ReVolt Technologies)

Zinc air batteries, which are already used in hearing aids, create an electrical current through a chemical reaction between zinc and the oxygen in air. Researchers have pursued rechargeable zinc air batteries for many years because zinc is relatively abundant and the internal chemistry, safe.

But there remain some technical challenges. After multiple charge-discharge cycle, the anode in zinc air batteries can become damaged and stop working. McDougall said ReVolt is trying to reach between 500 and 2,000 charge cycles, depending on whether the battery is used for consumer electronics or large-scale storage.

ReVolt engineers are working on a new design in which a zinc slurry is pumped through tubes that act as an air electrode, causing the chemical reaction that produces a current, McDougall explained. He expects it will take four or five years to commercialize the technology for large-scale applications, such as grid storage.

The company has raised 24 million Euros in funding, including an investment from power generator RWE of Germany, which is looking at the zinc air for storage on the electricity grid. ReVolt has applied for an ARPA-E grant aimed at breakthrough energy technologies but was not chosen in the first round of awards.

For vehicles, it makes sense to combine the relatively large energy storage of zinc air batteries with other storage technologies, McDougall said. Power-dense lithium ion batteries could be used for boosts of acceleration and ultracapacitors could capture energy from regenerative braking.

"You could increase the range of next-generation of electric vehicles with hybrid storage... You could get three times the range, eliminate the safety concerns, and cut the cost of the system," he said.

Updated at 10:55 AM pt with corrected timing for coin-size battery release.

[filipiak]

"... $24 million Euros ..."

I think you meant '?24 million', not "$24 million"

[filipiak]

Ok, so the euro symbol is not displaying in my comment. But I see you removed the dollar sign in the article.

[mlamonica]

thanks. I fixed that.

[ikramerica--2008]

I invested money in one of these Zinc Air companies 15 years ago, with patents and great technology. I no longer have that money. They declared BK, then sold the intellectual property to Duracell, leaving investors out in the cold. Duracell hasn't been able to make it work as desired.

[DemonDuck000]

The hybrid car drive train seems very complicated.

What about an automobile drive train like a diesel electric locomotive where the internal combustion engine runs only a generator for electric motors in the 4 wheels. It would be simpler, lighter and not
require recharging stations. The current gas station infra-structure -- already in place -- could be used and perhaps even small turbines could be used.

[zyxxy]

Chevy Volt. That is what you just described. Technically termed a "serial hybrid".

[sampath651]

There are 3 severe problems with zinc air technologies. 1. The aqueous KOH (potassium hydroxide) electrolyte absorbs or dries up moisture depending on the atmosphere. 2. The Carbon dioxide in the air reacts with the KOH to form carbonates resulting in loss of electrolyte properties. 3. The current generated is small and is dependent on the surface area and diffusion of air into the membrane. Only if all of these can be solved the rechargeable zinc / air will become a reality for large scale applications.