“There's a way to do it better - Find it.”

Thomas A. Edison

At the turn of the 20th Century, Thomas Edison patented a nickel-iron battery which had an undesirable quirk of producing hydrogen. A century later Prof. Dr. Fokko Mulder and his research group at Delft University of Technology saw the combined use of battery and electrolyser as an advantage for the new age of renewable power, and invented a super-efficient integrated battery and electrolyser - the Battolyser®.

Battolyser® can store and supply electricity as a battery. When fully charged it automatically starts splitting water into hydrogen and oxygen, acting as an electrolyser with an outstanding efficiency. Battolyser® is extremely flexible and robust and can arbitrage between power and hydrogen production. For example, the battery function can monetize daily power imbalances whilst the produced hydrogen can monetize seasonal power imbalances and provide feedstock to industries that cannot be electrified.

The technology is based on nickel-iron electrodes which have been available since Edison’s times. They are combined with alkaline electrolysis technologies that are commercially available today, with a proven track record of 20-30 years lifetime. The novel and ground-breaking integration of these technologies remarkably improves performance, lowers cost and increases uptime.

Product features

Below are some features of a Battolyser® that make it valuable for many use cases:

Operating range

Battolyser® is the only electrolyser with an operating range that goes below 0%.
Not only can you turn the system down to zero to prevent producing hydrogen from expensive non-renewable energy, but you can even revert it and sell power back to
the grid. In an off-grid project, the battery functions as back-up power when no renewable power is available.

Conversion efficiency

Battolyser® offers unprecedented stack efficiency of up to 85% at 30 barg outlet pressure. Save money on the largest cost component of green hydrogen, which is power and produce pressurized hydrogen at a system efficiency of 50.1 kWh/kg.

Robust to market changes

When energy prices are high, it may be more attractive to sell stored power rather than producing hydrogen. If the offtake of hydrogen is interrupted, Battolyser® can generate value as a battery. It’s an asset that lets you arbitrage between hydrogen and power markets.

Secure supply

Battolyser® is made from abundant raw materials delivered via secure supply chains required to meet the scale of an independent energy transition.

100% green hydrogen

Europe’s Renewable Energy Directive (RED II) provides valuable credits for hydrogen produced from additional, local and time-correlated renewable sources. Battolyser’s inherent flexibility allows you to follow any renewables load curves, comply with the strictest rules for temporal correlation, and produce 100% green hydrogen.

Low-cost raw materials

Battolyser® uses only iron and non-battery grade nickel electrodes, which are both abundant low-cost raw materials. The rest of the system also uses low-cost materials, due to the low temperature and alkaline environment, resulting in a much more affordable system overall.

Product lifetime

Battolyser® uses proven stable nickel and iron electrodes with a regenerative catalyst that is not subject to electrochemical degradation reducing the efficiency and expected lifetime, common in conventional electrolysers. The low operating temperature and alkaline electrolyte also ensure benign conditions and offer increased stack longevity

R&D facilities

We are continuously improving our facilities to support our product development and product innovation activities. Our current capabilities include:

  • Electrochemical characterisation lab: 100+ testing channels ranging between 10 A and 200 A (some with impedance capabilities)

  • The Battolyser Research Facility: a large testing facility to test stacks of commercial product size up to 15 kW

  • Workshop for constructing, building up, maintaining and adjusting test setups

  • Dedicated quality control room for analysis of externally manufactured parts

Future capabilities planned:

  • Materials characterisation facility (Scanning Electron Microscopy, X-Ray diffraction, elemental analysis, differential scanning calometry)

  • High pressure testing for increased product screening capabilities

  • Materials testing: tensile testing, materials ageing, surface roughness

  • Rapid prototyping facility (3D printing and materials cutting)

  • Powder handling laboratory: dedicated space to work with hazardous powders equipped to weigh, mix, coat, dry and sinter electrode active mass

  • General laboratory: equipped to perform standard tasks including weighing, mixing and component testing

Publications

Battolyser Systems holds the global patent portfolio to commercialize Battolyser® technologies and continuous further research with Delft University of Technology.

  • A Iranzoa, FM Mulder, Nickel-iron layered double hydroxides for an improved Ni/Fe hybrid battery-electrolyser, 10.1039/D1MA00024A.

  • FM Mulder, BMH Weninger, J Middelkoop, FGB Ooms, H Schreuders, Efficient electricity storage with a Battolyser®, an integrated Ni–Fe battery and electrolyser, Energy & Environmental Science, 10 (2017) 756-764.   

  • BMH Weninger, FM Mulder, Renewable Hydrogen and Electricity Dispatch with Multiple Ni– Fe Electrode Storage, ACS Energy Letters, 4 (2019) 567-571.

  • Barton et al., Characterisation of a nickel-iron Battolyser®, an integrated battery and electrolyser, Frontiers in Energy Research 8 (2020) 509052.

  • International Energy Agency publication: ‘Renewable Energy for Industry’, C. Philibert, IEA

  • EU Integrated SET-Plan on batteries