Battery technology explores new applications

Modern shipbuilders are trying to reduce noise, CO₂ emissions and water pollution. One solution for some ships is electric propulsion. Electric motors are particularly suitable for ships that cover many short distances, such as ferries and icebreakers. Batteries don’t allow you to stay at sea for days. The EU project NAVAIS, of which VITO is also a part, is examining the conditions that would facilitate electric propulsion for ships.

Challenges

“VITO is working on three challenges within NAVAIS,” says Peter Coenen, senior researcher Battery Technology. “The first is thermal management. Batteries require a constant ambient temperature of around 20 degrees Celsius. But on ships, it can be very hot or very cold. The thermal conditioning of a battery is therefore important. VITO is designing calculation models that examine how batteries will react in the tropics or at the North Pole.” “A second aspect is the aggregation of battery modules. A ship can have different sizes of batteries on board. They each have their own battery management system (BMS). In the case of multiple batteries, that BMS will be modular. But a captain needs a single number that indicates how much power and autonomy the ship still has. VITO therefore is developing an algorithm to merge battery modules.”

Super-fast charging

A third research topic is the speed at which batteries can be charged. A typical ferry makes a crossing of half an hour and is then at the dock for ten minutes before departing again. The battery needs to be charged in these ten minutes. But with most batteries, charging takes longer than the use. “To prevent shipbuilders from having to install super-large batteries, we are working on faster charging technologies,” says Peter Coenen. “The hard part is that a battery can be damaged if you charge it with too much power. By simulating the electrochemistry of a battery, we can determine the maximum allowable current.”

Modular design

The faster charging technology is part of a new method of designing ships. Traditionally, a shipbuilder waits for a customer request before designing a ship. Only after the customer approves the design, the shipbuilder can make an offer. Thus a lot of time and money is spent designing ships that may never be built. “At NAVAIS we are developing a method that divides vessels into modules. These modules allow a shipbuilder to design faster and cheaper,” says Peter Coenen. “The European Commission hopes to keep the European shipbuilding sector competitive with this approach. The project includes some fifteen partners, including Dutch shipbuilder Damen. Damen’s employees should be able to use the new design process within four years.”