As the maritime industry navigates an increasingly complex energy transition, the search for practical, scalable and sustainable solutions has never been more important.Recognising this need, AYK Energy is helping to provide the technologies and solutions required to support this evolving landscape. Founder & President Chris Kruger explained more to Imogen Ward.
After dedicating years to building batteries for the automotive industry, Founder & President Chris Kruger took a leap of faith that would change the maritime industry forever.
“Corvus approached me in 2010 to start an engineering team there,” explained Mr Kruger. “This was a real privilege, and it resulted in us bringing the very first propulsion batteries to the maritime sector. That’s really where the idea for AYK Energy evolved from.”
The journey to now
While at Corvus, Mr Kruger and his team of engineers focused on developing world-class batteries for propulsion and UPS applications. Once the technology was ready, the team worked closely with DNV to secure certification for the batteries, laying important foundations for their future development in the marine sector.
However, despite this progress, the maritime industry remained hesitant to embrace battery power. In 2015, Mr Kruger took a step back to understand why batteries were not gaining the same traction in maritime as they were in the automotive sector.
“I looked into what was really holding the battery market back in the marine industry, and it all came down to cost,” explained Mr Kruger. “We were competing with traditional bunkering fuels, something that is very difficult to do with a new technology in a conservative market place.
“The marine industry doesn’t look at the green space as a motivator; it is down to legislation or money. And the price of batteries just didn’t make sense for them. The only solution would be to bring down the cost of the battery – something that wouldn’t be possible outside of China.”
Recognising that cost competitiveness would be critical to unlocking wider marine battery adoption, Mr Kruger established AYK Energy in China. The journey was gradual, with the company initially providing battery management systems (BMS) before steadily expanding its capabilities and developing the wider battery technology that would become central to AYK’s offering.
“Our first big break came in 2019, when I made a bet with the Director of Marine at EVE, a cell manufacturer,” recalled Mr Kruger. “He felt it would be impossible to get DNV type approval for a marine battery and offered his facility and test equipment to see if I could do it. Just after that COVID hit in 2020, I went to China and with two engineers we designed, developed and gained type approval for the battery within just six months.”
Knowing that a conservative maritime industry would require more than certification to embrace a new battery supplier, Mr Kruger set out to prove the technology in practice. That opportunity came in 2021, when AYK convinced Wärtsilä to put its battery through testing, a company that remains one of its closest customers to date.
The core components
Today, AYK’s Onboard Integrated Battery System provides a compact, fully integrated energy-storage solution designed specifically for the demands of marine operations. Bringing battery modules, thermal management, power electronics interface and safety systems together within a single onboard architecture, the system is designed to maximise available space while delivering high-performance power.
When it comes to marine battery systems, cooling is essential as the cells generate heat during charging and discharging. AYK relies on two different cooling methods, allowing its modules to be tailored to different power and performance requirements.
For lower C-rate applications, AYK relies on air-cooled modules that use forced airflow to regulate cell temperature. This is a great, cost-effective solution that has proven its reliability over the years. Using air-cooled modules, AYK delivered in 2024 the largest batteries at the time (12MWh) for two E-Flexer ferries with Brittany Ferries.
As demand shifted towards higher energy densities and more powerful applications, the company recognised the need for a more advanced approach. This led AYK to develop its liquid-cooled modules, providing greater thermal control for increasingly demanding marine applications.
Development of AYK’s liquid-cooled modules began in early 2025, around the Chinese New Year, with type approval secured by October. Recognising the potential of the technology to raise the bar for marine battery performance, Mr Kruger quickly turned his attention to bringing it to market.
The breakthrough came when a Danish ferry operator, selected AYK for a landmark 55MWh battery project. According to Mr Kruger, the project would not have been possible without AYK’s liquid-cooled technology.
“This high-speed ferry project required a 55MWh battery, which is the largest battery on the water to date,” shared Mr Kruger. “The owner was looking for a high volumetric and gravimetric energy density energy storage solution. Several battery suppliers were evaluated based on energy density, safety and maturity. Finally, the AYK liquid cooled battery solution was selected as the best fit for the project.
“We matched their volumetric energy density requirements perfectly.”
Scaling for demand
With its new liquid-cooled technology gaining momentum, and demand for high-performance marine batteries growing, AYK recognised the need to expand its manufacturing capacity. Having originally operated in a 5,000sqm facility, the company has since expanded, adding a further 5,000sqm.
The expansion builds on the state-of-the-art factory AYK established in 2023 and provides the capacity needed to support the company’s growing portfolio.
With this additional space, AYK has been able to successfully install an automated line for its liquid-cooling modules.
Alongside its Onboard Integrated Battery System solution, AYK has been developing a 20’ containerised battery system. The AYK marine battery container (MBC) is swappable with industry standard interfaces and can be stacked next to normal cargo containers on feeder vessels. With an energy of 2.8MWh per container, 28MWh can be installed in a 20’ container footprint. There are eight levels of safety to prevent thermal runaway, making this the safest battery container in the world.
Although the MBC has been developed for feeder vessels, the modularity, movability as well as stacking make this MBC ideal for many marine applications. The units can be permanently installed on the top deck, or inside a vessel, removing the need for a custom battery room design. On the other hand, by providing a mobile source of stored power, the solution aims to help bridge gaps in shoreside charging infrastructure.
In short, the MBC offers operators greater flexibility as the maritime industry moves towards electrification. The MBC is already in production with several orders on hand.
“Eventually, we will have the capacity to produce a container a day,” said Mr Kruger, in conclusion. “We have already drawn up the plans for that and are just waiting on the uptake before we invest further money into the factory.
“Ideally, we will see things move into place towards the end of 2027. Until that point, our focus will remain on our current battery technologies, while marketing the half-height containers. Ultimately, our goal is to make battery power more accessible to the marine industry, and I truly believe our technology will be a real gamechanger.”