Marine battery manufacturer AYK Energy has signed a second deal with Spanish ship owner Mureloil to supply diesel electric hybrid systems.

AYK will deliver the same 4.2 MWh Aries+ battery system to Mureloil’s 8000 DWT product tanker Bahía Beatriz as its sister vessel the Bahía Candela, also a 8000 DWT tanker.

Bahía Beatriz is currently under construction at the Astilleros de Murueta shipyard, outside Bilbao. AYK’s Spanish agent VULKAN will help install the battery system. The two vessels can operate on full electric power during port operations. 

The battery system will use lithium iron phosphate (LFP) technology, which AYK said can outperform nickel manganese cobalt (NMC) batteries.

“NMC has been the most commonly used battery chemistry because of its supposed greater density, but its chemistry is known to be much more dangerous than LFP,” said AYK Energy founder Chris Kruger. “AYK is showing that LFP can outperform NMC and deliver greater energy density, higher safety and better value.”

The vessels will double Mureloil’s capacity to transport biofuels and methanol, strengthening the shipping line’s presence in the sustainable marine fuels sector.

Demand for battery power is further being fueled by mounting regulatory pressure on ship owners, who face greater scrutiny and penalties under new laws like FuelEU and the EU Emissions Trading System.

“The regulatory squeeze is real,” Kruger said. “With the new sustainability reporting requirements, ship operators know they need affordable carbon cutting solutions like marine batteries that deliver.”

In June 2025, AYK’s latest range of marine batteries, including Pisces, Pisces +, OrionAN, OrionAN+ as well as aluminum versions of AYK legacy modules, received type approval from the classification society DNV.

The contract with Mureloil follows a deal to supply Spanish ferry operator Baleària with two electric catamaran ferries to operate between Tarifa in the south of Spain and Tangier, Morocco.

“The time for marine batteries has come,” Kruger said. “Although these vessels are hybrid diesel electric we are now seeing that the technology is there to go fully electric not just on ferries, OSVs and workboats but also tankers like these. But seeing batteries on tankers is a significant moment for electric power. The energy density of batteries is increasing, the price is reducing and the payback period is quicker.”

Source: AYK Energy