Battery-Electric vs Fuel Cell Trucks: Key Differences Explained

Battery-electric and hydrogen fuel cell trucks share far more hardware than their labels suggest. Mercedes-Benz Trucks proves it with the series-production eActros 600 and developing NextGenH2 Truck. Both use the same integrated electric axle, recover braking energy and deliver immediate torque.

The difference sits upstream of that axle. The eActros 600 carries electricity in three battery packs. The NextGenH2 converts liquid hydrogen through two fuel-cell units and uses a smaller battery for power peaks. This split changes range, replenishment time, infrastructure and fleet economics.

One Electric Driveline, Two Energy Paths

In both trucks, current reaches an integrated eAxle between the rear wheels. Mercedes-Benz Trucks packages two motors, power electronics and a four-speed transmission into one unit. The gearbox keeps the motors in an efficient operating band during loaded starts, motorway cruising and steep climbs.

Shared architecture reduces engineering duplication and gives workshops a common service base across battery-electric trucks and fuel cell trucks. In addition, both systems reverse current during deceleration, turning the traction motors into generators that return energy to an onboard battery.

Shared components include:

• The integrated electric axle and four-speed transmission
• The aerodynamically developed ProCabin
• Multimedia Cockpit Interactive 2
• High-voltage and electronic architecture
• Active Brake Assist 6, Front Guard Assist and Active Sideguard Assist 2
• Regenerative braking, low exterior noise and zero tailpipe CO2 emissions

Core Specifications Side by Side

How the eActros 600 Stores and Uses Electricity

The eActros 600 battery system carries 621 kWh across three 207 kWh lithium iron phosphate packs. LFP cells avoid nickel and cobalt, support long life and release more than 95% of installed capacity. That usable share equals roughly 590 kWh and supports a 500 km target at about 40 tonnes.

Looking at the data, using 590 kWh across 500 km implies about 1.18 kWh per kilometre. Speed, weather, gradients, trailer aerodynamics and auxiliary loads alter that figure. Refrigeration or winter heating raises demand.

The 800-volt axle delivers 400 kW continuously and 600 kW at peak. Five recuperation levels manage downhill speed, while optional one-pedal control reduces service-brake use. Predictive Powertrain Control reads topography, road geometry and traffic signs, then times acceleration, coasting and gear changes.

Charging Fits Regulated Driver Breaks

The truck accepts up to 400 kW through CCS. Its Megawatt Charging System targets 20-80% in about 30 minutes from a suitable one-megawatt charger. That 60% window represents 372.6 kWh, enough for a substantial second driving leg during a statutory break.

This model favours fixed routes, depot returns and reserved charging. Mercedes says roughly 60% of its European customers' long-distance trips cover less than 500 km. Consequently, many operators can charge overnight and avoid public energy stops.

How the NextGenH2 Produces Electricity Onboard

The NextGenH2 Truck carries 85 kg of liquid hydrogen in two linked, insulated tanks. At -253 degrees Celsius, the fuel has far greater volumetric density than compressed hydrogen. Drivers can refuel from either side through the sLH2 standard in 10 to 15 minutes.

Two cellcentric BZA150 fuel-cell modules sit under the cab and deliver 150 kW each. They combine hydrogen with oxygen, producing electricity for the eAxle and water vapour. The 101 kWh LFP battery captures braking energy and supports acceleration or long climbs.

Specifically, the truck supplies 340 kW in Economy mode and 370 kW in Power mode. The battery covers demand spikes, letting the fuel cells run near a steady load. GenH2 customer trials recorded 5.6-8.0 kg/100 km at gross weights from 16 to 34 tonnes.

Those rates give 85 kg a theoretical span of 1,063-1,518 km before reserves. Load, altitude, temperature and speed narrow the spread. A 40-tonne GenH2 prototype still travelled 1,047 km on one fill.

Packaging and Thermal Control Define the Hydrogen Truck

Hydrogen hardware demands extra space. Daimler places boil-off controls, cooling circuits and support equipment in a Tech Tower behind the cab. Engineers shortened the wheelbase by 150 mm to 4,000 mm, improving semitrailer compatibility under EU length rules.

The Tech Tower controls pressure and heat under high thermal loads. Sensors monitor leakage, while side panels with crash structures protect the tanks. Its management system supports enclosed parking, and the cab retains two beds.

The ProCabin cuts drag coefficient by 9% against the previous cab in Daimler's 40-tonne motorway simulation. On the eActros 600, an 80 mm longer nose, sealed front, underbody panels and extended rear flaps reduce turbulence. Every saved kilowatt-hour protects range and charging time.

Operational Fit and Cost Drivers

From an expert perspective, direct electricity gives the eActros 600 a simpler energy chain. Grid power enters the battery, an inverter controls current and the eAxle creates motion. Hydrogen production, liquefaction, transport and fuel-cell conversion add losses, making clean hydrogen cost decisive.

By comparison, hydrogen buys time and range. An 85 kg fill in 10-15 minutes implies 5.7-8.5 kg per minute. A haulier running irregular cross-border work may value that speed, provided stations serve the required corridors.