NMC batteries for commercial vehicles: high-performant and safe

NMC cells optimised for commercial vehicles

The individual properties of a lithium-ion battery can be influenced by the use of different materials for the positive and negative electrodes (cathodes and anodes). In this context, experts speak of “cell chemistry”. MAN uses NMC cell chemistry (nickel-manganese-cobalt) in its batteries. The cathode is made of a blend of nickel, manganese and cobalt. This combination offers high energy density, stability and safety. The anode is made of graphite, a form of carbon.

Other batteries use LFP cell chemistry, which uses lithium and iron phosphate for the cathode. This material is also thermally stable, safe and durable, although it offers a lower energy density than NMC batteries. MAN has carried out intensive comparisons of the two technologies and has made a considered decision to use NMC cells for the current generation.

“We have developed, adapted and optimised the NMC cell chemistry,” reports Dr Michael Bernath, head of battery development at MAN. “We have been able to develop a battery that stands up to the tough conditions of day-to-day use in commercial vehicles. It offers high energy content at an economical price with low weight and compact size – and all without compromising on operational safety.” Every MAN battery is subjected to stringent testing to ensure its durability in every conceivable scenario. These tests are often stricter than legally required.

Smart BMS and extensive testing guarantee safety

However, the safety of a vehicle battery depends on more than just the cell chemistry. The control electronics surrounding the energy storage also play an important role. At MAN, a battery management system (BMS) constantly monitors the condition of the cells. If, for example, an unexpected event occurs, the BMS takes internal measures to ensure a safe state. In the event of an accident, the BMS immediately disconnects the battery from the rest of the vehicle (high-voltage emergency cut-off).

In addition, the BMS uses an intelligent heating and cooling system to keep the battery within an optimum temperature range at all times – too high temperatures could damage the battery, while too low and performance is affected. The BMS also predicts how the battery is ageing on the basis of the individual usage profile. This means that its lifetime can be optimised and, if necessary, repairs or replacements can be undertaken. To summarise, we can say that the BMS improves efficiency and safety, reduces ageing and extends the lifetime of the battery.