Digging up materials and hauling them around mining sites is inherently dirty work, but it is set to get a little cleaner on the back of a heavy duty electric vehicle currently under development. Some time in the next few months, the Komatsu HD 605-7 will start carting materials down from a Swiss mountain powered only by a mammoth 4.5-ton battery pack, said to make it the largest electric vehicle in the world.

The vehicle in question is a used truck built by multinational machinery maker Komatsu. Now a team of researchers in Switzerland has gotten its hands on the heavy duty diesel dumper, and set about repurposing it as a prototype for an all-electric mining vehicle that can carry heavy loads in a more environmentally friendly way.

This involved disassembling and reconstructing the truck, removing the diesel engine and making space around the chassis for the huge battery packs, which will consist of 1,440 nickel manganese cobalt cells and boast 700 kWh of storage capacity. According to the team, which includes scientists from Swiss research institute Empa and the Kuhn Group (which sells Komatsu dumper trucks around Europe), this will be the largest battery pack ever fitted to a land vehicle.

When finished, the prototype will be put to the test using its 65-ton loading capacity to haul materials down from a cement works quarry on Switzerland's Chasseral mountain 20 times a day. During each of those trips, regenerative braking will charge up the battery pack by 40 kWh, which the team says will provide more than enough energy to make it back up the hill with electricity leftover to feed back into the grid.

Because this project represents new territory for electric vehicles, the team will be watching closely to see how the truck performs and keeping an eye out for any malfunctions. This will mean running overcharging tests and purposely mistreating some of the nickel manganese cobalt cells with a steel nail to see how the batteries respond.

"Nickel manganese cobalt cells are also the choice of the German automobile industry when it comes to the next generation of electric cars," explains Empa battery expert Marcel Held. "Some batteries start smoking, others burst into flames. The crucial thing in this instance is to make sure the neighboring cells are not damaged by the fire and heat, otherwise there is the risk of a chain reaction."

If all goes to plan, Empa says as many as eight vehicles could enter use at the cement works site, and the prototype could open up new possibilities when it comes to large-scale construction machines.

Source: Empa