The trend in the worldwide mining of copper, nickel, cobalt, coal, gold and other valuable raw materials is clearly visible: More and more mine operators - both above and below ground - are opting for the electrification of their vehicle fleets. Mines such as the Borden Lake Mine of Goldcorp in Canada are using mining vehicles, including drilling and anchoring equipment which are furnished with battery systems from AKASOL AG in Germany.
The Borden Lake Mine near Chapleau in the state of Ontario is unique: It is the first new gold mine in Canada to be fully electrified. This will result in lower costs for the operators of Goldcorp Inc, improved health protection for the employees and ultimately a reduced ecological footprint. Commercial gold production at the Borden Lake Mine is expected to commence this year on a purely electric basis. The mining area covers approximately 1,000 square kilometers.
However, constructing a mine that completely dispenses with diesel-powered vehicles is not an easy undertaking. In order to carry out the work, more than a dozen vehicles can be needed - heavy equipment whose conversion to a purely electric drive or replacement by new vehicles poses an enormous challenge.
High-performance battery systems from Germany
So in 2016, the first contact between several partners was established: The engineering company Medatech Ltd. from Canada, which with its ALTDRIVE Systems division specializes in sustainable drive trains for the mining industry, finds what they are looking for in the liquid-cooled battery systems from AKASOL in Germany.
"The AKASOL concept for high performance battery system has from the outset included much more than just standards such as safety, performance and durability," recalls David F. Lyon, Business Development Manager and Mechanical Engineer at Medatech. "The solutions are characterized by the remarkable combination of exceptionally high energy and power density, extremely compact design, modular construction and maximum flexibility."
Before contacting the battery manufacturer, the mining equipment manufacturer MacLean Engineering, also from Canada, had contracted Medatech to implement drive trains for drilling and anchoring machines. They use a lithium-ion battery system of the type AKASystem 15AKM POC 46Ah based on lithium-nickel-manganese cobalt cells, which meet the customer requirements and convince with high cycle stability, safety and fast charging capability.
"The customers set a number of strict criteria," reports Felix von Borck, Senior Key Account Manager and co-founder of AKASOL AG. Medatech had been looking for a battery with liquid cooling and active thermal management in order to maximize performance and service life in daily and hour-long underground use. AKASOL uses a particularly effective water-glycol mixture that maintains a core temperature of 20 to 25 degrees even under high stress and almost independently of the ambient temperature.
"The same underlying standard applied to all criteria: safety before price," says Lyon of Medatech. "After much discussion and extensive testing, AKASOL was the only company from the pool of candidate providers that met our requirements, while scoring top marks in the process."
For mining applications, however, a special resistance is also required, which is why the two partners installed particularly robust and secure casing. Another customer request: Experience with real operating data should already be available.
In the mining vehicles, the liquid-cooled battery system has a storage capacity of 30.6 kWh at a nominal voltage level of 666 V, enabling it to reach 77 kW on average. At peak times it delivers an output of 406 kilowatts over a period of ten seconds. It is fully operational at ambient temperatures between -25 and +45 degrees Celsius and comes equipped with an intrinsically safe overload and over-voltage element. The battery system serves as a central component in the ALTDRIVE electric drive train. In addition, the systems can be charged in just 15 minutes.
ALTDRIVE was designed as a technical system to replace diesel engines in heavy commercial vehicles. The alternative drive trains consist of a hybrid or fully electric engine with AKASOL's battery systems at the heart. The ALTDRIVE solution can be adapted to heavy equipment such as trucks, tractors, excavators, buses, dump trucks, light rail vehicles, and mining vehicles.
Since 2016, the partners from Germany and Canada have been cooperating to provide electrified vehicles for the Goldcorp gold mine and other customers like GHH from Germany. To date, 84 battery systems have been installed in 28 vehicles and are used daily in the mining industry. Two to three more vehicles are added each month. These include the world's first grader retrofitted with an electric drive train. For this purpose, the drive train of the MacLean 977 construction vehicle with similar characteristics was used to electrify a Caterpillar 12M3 leveller.
For Goldcorp, the switch to diesel-free gold mining is an important step towards a lower environmental footprint. Every electric vehicle reduces fuel costs by 53 percent compared to diesel. CO2 emissions are also minimized thanks to locally emission-free vehicles and the use of green electricity. In a typical mine, operators such as Goldcorp save 7,500 tons of CO2 per year, three million liters of diesel, one million liters of propane and 35,000 megawatt hours of electrical energy.
According to Medatech, higher investment costs will be offset by savings, such as halving the high cost of ventilation in the mines. John Mullaly, Vice President of Corporate Affairs and Energy at Goldcorp, is also convinced of the rapid breakthrough of electromobility in mining: "I expect the rapid deployment of battery-powered vehicles in Canadian mines within the next five years. This applies to both new and existing mines."
Even if savings from obsolete air conditioning systems are no longer applicable, a feasibility study by Medatech customer Nouveau Monde Graphite shows that complete opencast electric mining operations pay off. This was investigated as part of the study for a mine near Saint-Michael-des-Saints in the Lanaudiere region of Quebec.
NMG is a major graphite manufacturer who is interested in producing graphite - a material needed by battery cell producers such as Samsung, CATL or LG for Li-Ion battery cells - with the lowest possible ecological footprint. If NMG succeeds in realizing the very first electric opencast mine, the graphite will be produced with an as-yet unrivaled small footprint - and battery systems from AKASOL.
Pictures: Copyright MEDATECH