25 Liebherr piling machines | Dossier E-Mobility Engineering | July/August 2026 Then, just by moving the joysticks, they can move the leader,” explains Mewes. “There is not much work to do except to stop the machine once the pile is driven. The energy involved normally depends on the pile cross-section and, as the operators are paid by the number of piles driven per day, they typically need the operation to be as fast as possible. So, it was important that the electric machine had at least the same performance as the diesel engine.” Liebherr adapted its conventional hydraulic piling rigs into battery-electric machines while maintaining familiar architecture. They can operate on mains voltage at 400 V AC (running on 3-phase with neutral and protective earth wires) or they can use the onboard battery system. The rig has two hydraulic pumps, each of which delivers 275 litres per minute for the working tools, with a separate pump delivering 130 litres per minute for the kinematics. The maximum working pressure is 350 bar and the hydraulic oil tank, which is designed for the use of synthetic environmentally friendly oil where possible, has a capacity of 600 litres. When the carrier has to move, traction is delivered through a pair of crawler tracks, with fixed axial piston hydraulic motors. These can provide a tractive force of 440 kN in the LRH 100 or 665 kN in the LRH 200 – which enables the huge heavy unit to reach a crawling speed of 2 or 1.3 kph, respectively. The side frames have hydraulic chain tensioning and the vehicle is kept stationary with a hydraulically released, spring-loaded multi-disk holding brake. “We use a direct AC electric motor to run the regular functions of our construction machine,” explains Mewes. “The hydraulic system is all the same as the one on the diesel version, but on this vehicle we just transfer the electric energy from the batteries or direct mains plug-in system to run the electric motor. The piling mechanism is still a hydraulic operation, with an upper carrier and lower carrier, a hydraulic cylinder at the leader and a hammer, which is lifted by the hydraulic cylinder and accelerated downward by hydraulics. “Instead of the engine, gearbox and cooling system, we have the electric motor, battery management system, the thermal system and the terminal system. The motor is located where the diesel engine normally is. We have added a charging plug in the middle of the tracks, which can be positioned front or the back, and we added an area at the top of the upper carrier for the battery storage. It is a direct drive solution, so we eliminate losses in the gearbox from the diesel engine, and we have a belt drive to take the output of the motor to the wheels.” The ‘unplugged’ piling machines can be used with direct power from an electric supply or use the onboard battery
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