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LHD BATTERIES JANUARY 2017 • E&MJ; 37 www.e-mj.com Technical Specifications Artisan's 3-mt (tramming capacity) 153 is 225 inches (in.) long by 65 in. high by 60 in. wide. Total power is 214 kilowatts (kW); tractive effort, 75 kilonewtons; and loaded speed (on 17% grade), 12 kilome- ters per hour (km/h). The powertrain mo- tor's peak power is 127 kW or 170 hp. Its peak torque is 695 newton meters (nM), or 513 foot pounds (ft-lb). It is pow- ered by a 600-volt (V) DC, 88-kW hour (kWh) lithium iron phosphate battery. The bucket is 1.2 cubic meters (m 3 ), or 1.5 cubic yards (yd 3 ). Lift breakout force is 4,899 kilograms (kg) (10,888 pound force [lbf]); tilt breakout force is 7,031 kg (15,500 lbf). Total operating weight is 9.5 mt. Using technology proven in coal mines and tested at hard rock mines, General Electric's 7-mt (tramming capacity) LHD runs on a 320-V (287 kWh) lead acid bat- tery and features a 4-yd 3 (3.1-m 3 ) bucket. It is 369 in. long by 94 in. wide by 88 in. high. Operating weight is 34 mt. Lift breakout force is 13,662 kg (30,120 lbf). Tilt breakout force is the same. Operating range for the two-battery system is from six to 10 hours (three to five hours per battery). "The battery exchange system is integrated into the vehicle itself, so it doesn't require mine infrastructure to exchange batteries," Pat Jansen, senior engineer, underground mining, said. GE is developing lithium battery technology with Li plus exchange or rapid charge, which will add flexibility and adaptability, GE reported. RDH Mining Equipment's Muckmas- ter 600EB LHD features a 470-V DC lithium iron phosphate battery system that requires two to three hours to charge and operates for four hours at 400 amps per hour. "They can swap out the bat- tery, which takes 15 to 20 minutes, and then the scoop is back in operation," Courchesne said. The bucket capacity is 3.4-5.4 m 3 (4.5 to 7 yd 3 ); nominal payload capacity is 11 mt. The LHD is 10 m long by 2.5 m high by 2.4 m wide. Approximate weight is 31 mt. The 100- 200 hp four-speed electric powertrain motor is liquid cooled and features AC traction drive. RDH's 300EB LHD also is powered by a 470-V DC lithium iron phosphate bat- tery system that requires 90 minutes to two hours to charge and operates for four hours at 260 amps per hour. The bucket is 1.5-2.3 m 3 (2 to 3 yd 3 ). With a 2.3-m 3 bucket, the LHD is 8.3 m long by 1.8 m wide by 2.2 m high. Approximate weight is 15.8 mt. The liquid-cooled, 100-300 hp three-speed electric powertrain motor employs AC traction drive. Atlas Copco's 7-mt (tramming ca- pacity) two-battery Scooptram ST7 LHD offers a quick battery change strategy, which enables 24/7 operation, and an adjustable bucket that comes standard at 3.1 m 3 volume at 2.2 tons per m 3 (t/m 3 ) material density. The Artisan 1200 Series traction motor's peak power is 149 kW. The lithium iron phosphate battery mod- el is also made by Artisan, and is 630 V DC, or 165 kWh. Hydraulic breakout force is 11,750 kg (25,904 lbf). Mechan- ical breakout force is the same. On level grade, in fourth gear, the maximum speed is 23.1 km/h. It is 90 in. wide. Approxi- mate weight is 21.5 mt. Unveiled at MinExpo 2016, Sandvik's 6.7-mt (tramming capacity) LH307B is powered by lithium titanate oxide bat- tery technology, which features rapid (15 minute) recharging for continuous opera- tion with a single battery pack. Compat- ible with Sandvik mine automation and information management systems, and comprised of components from the diesel LH307, it features a 6.7-mt payload and a 3-m 3 (3.9-yd 3 ) bucket. Peak engine pow- er is 150 kW. Peak speed is 26 km/h. Lift breakout force is 13,700 kg (30,203 lbf). Tilt breakout force is 11,400 kg (25,133 lbf). The diesel LH307 is 340 in. by 83 in. by 87 in. Approximate weight is 22 mt. The single-battery quick recharge sys- tem nixes the need for backup batteries and a dedicated swap, service and re- charging area, which cuts capex costs. Five of the six above-mentioned LHDs are powered by lithium ion batteries, technology that had to overcome several hurdles before being deemed safe, reli- able and practical. Lithium Battery Development Lithium ion batteries are everywhere. They are found in mobile devices, flashlights, laptops, and various vehicles. A 2013 report 1 co-authored by Dr. Nieto summa- rized how the technology works. "Lithium (Li)-ion batteries work by shuttling Li-ions between molecular lattices, which tempo- rarily hold the lithium until the cell is in use. Non-aqueous electrolytes are used to keep the Li-ions mobile between the lithium hosts at the negative and positive electrodes." The report stated, "There are a plethora of compounds, which can be used for the positive electrode. The most common positive electrode materials in- clude lithium transition metal oxides (Li- M 2 O 4 or LiMO 2 ) and lithium transition met- al phosphates (LiMPO 4 ). Graphite is most commonly used for the negative electrode, although it is certainly not the only option. Lithium titanate spinel (Li 4 Ti 5 O 12 ) is also a viable option and is praised for being a safer alternative to graphite with a high cycle life (~20,000) and rapid (constant current) charging ability." Nieto mentioned a minimum of three challenges to development and wide- spread use of the technology to power mining machines. Lithium batteries fail with abuse, spe- cifically punctures, Nieto reported. "A puncture could create an internal short, which would generate a large amount of heat. If the hermetic seal has been breached, moisture from the environment could react with the lithium generating 1 Using Modern Battery Systems in Light Duty Mining Ve- hicles, by Richard S. Schatz, Antonio Nieto, Cihan Dogruoz and Serguei N. Lvov; Department of Energy and Mineral Engineering, The EMS Energy Institute, The Pennsylvania State University, Pennsylvania, USA, November 2013. RDH's electric 600EB, with customizable bucket capacity and style, offers an optional remote control system upgrade. 'Diesel-powered equipment underground is a health and safety issue,' Jeannot Courchesne, vice pres- ident, said. (Photo: RDH)