A LOT OF ZINC AIR – EU project develops zinc-air batteries for the utility market

A LOT OF ZINC AIR – EU project develops zinc-air batteries for the utility market

A LOT OF ZINC AIR – EU project develops zinc-air batteries for the utility market Energy Storage Journal

A European project is developing a cheaper utility storage device using zinc-air battery technology.
Zinc-air batteries, which provide electrical power through the electrochemical oxidation of zinc by oxygen are widely available as disposable button cells used to provide power for hearing aids. But for utility and grid-scale storage zinc-air flow batteries have the advantage of having higher power and energy density than vanadium redox flow devices, while being relatively potentially cheap to manufacture compared with various batteries.
Commercial efforts

The need for cost-effective grid storage bought about by increased use of renewables such as solar and growing electricity demand that cannot be met by existing grid infrastructure is driving efforts by companies around the world to commercialise zinc-air flow batteries. US firm Eos, for example, has developed a zinc energy storage system for the electric grid that can be sold for $160/kWh (about €120/kWh) and is rechargeable over 10,000 cycles, equivalent to 30 years.

The company is scaling up battery prototypes in 2013 in preparation for manufacturing and delivery of MW-scale systems to customers in 2014. Others include Zinc Air Incorporated (ZAI), which is commercialising technology developed with Department of Energy (DoE) support over 10 years.
Powair project

In Europe, a group of companies and research partners are developing a zinc-air flow battery, under Seventh Framework Programme (FP7) funding. The Powair project, which began in November 2010 and will run until November 2014, is being led by UK energy research company C-Tech Innovation, which draws on over 40 years of experience in electrochemical processes development, design and building of industrial electrochemical systems for industrial customers.

Other partners include CEST in Austria, which has laboratories with electrochemical equipment and has carried out extensive work into metal deposition and dissolution, Fuma-Tech in Germany, which produces ion exchange polymers and membranes for fuel cell and other electrochemical applications, as well as Green Power Technologies in Spain, DNVKEMA and E.On Engineering. University of Southampton and University of Seville are the research partners.
The total project budget is €5.1 miilion, which includes a grant from the EU of
€3.6 million.

John Collins, project manager at C-Tech Innovations, says: ‘The Powair project came about because we were looking for a flow battery technology that would be more cost-effective to manufacture in-line with what electricity companies would be willing to pay. So while their efficiency may not quite match some other battery technologies you are essentially playing off lower cost against overall efficiency.’

The efficiency of the batteries developed under Powair will be in the region of 5-10% lower than a typical flow battery.
Goals

Objectives of the project include developing zinc-air batteries with four times the energy density of existing flow batteries and significantly reduced cost, plus developing, designing a modular energy system capable of plug and play expansion via a novel modular distributed power converter. Both Green Power Technologies and the University of Seville have expertise in power conversion.

Towards the end of the Powair project a 10 kW demonstrator will be developed for evaluation that could precede a commercial system with a target cost of €100-150/kWh with an estimated service life of around 10 years, though the majority of the system should operate for an additional 10 years or more, following maintenance and servicing. The demonstrator will be evaluated for operation and grid compatibility on a test grid by DNVKEMA, a global energy consultancy and certification business with extensive facilities for carrying out different simulated test conditions for the batteries and systems.

‘THE POWAIR PROJECT CAME ABOUT BECAUSE WE WERE LOOKING FOR A FLOW BATTERY TECHNOLOGY THAT WOULD BE MORE COST-EFFECTIVE TO MANUFACTURE IN-LINE WITH WHAT ELECTRICITY COMPANIES WOULD BE WILLING TO PAY.’

While it is too early a stage in the project to have a route to market finalised, the project team is considering potential options as the partners, between them, have the know-how and facilities, via Fumatech, to manufacture the air electrodes, which are the battery’s key component.
‘Scaling timeframes are dependent on module size you are aiming for. In the 5-10 kW module range, then we anticipate that it could take another year on top of a year of evaluating the prototype to commercialise an improve version of this.’ explains Collins. Batteries could be commercialised from late 2016.
It is likely that initially the batteries will be used in pilot projects and small scale applications such as local grid reinforcement. This year and next the focus will turn to finding potential supply chain partners, including providers of production tools and equipment in order to commercialise the battery technology.