Lift Truck Tips: Fast-charging gains power
Opportunity fast-charging and an 80-volt battery may give electric lift trucks more of the capacity and performance attributes of internal combustion trucks.
February 01, 2010 - MMH Editorial
Sometimes the most powerful mixtures are made from inert elements. Take fast-charging and 80-volt lift trucks, for example. Neither of those elements has been a potent force in U.S. markets. However, the need for better energy efficiency and more powerful performance may be the catalysts for combining them to form a new solution.
I’ve talked with several lift truck suppliers who either are or will be introducing 80-volt products into their lines. The demand for a more carbon-friendly alternative to internal combustion engine (IC) models is on the rise. For many IC stalwarts, the only thing keeping them from adding their voices to that demand is the idea of allocating the space and time to manage battery changing and charging. That’s where fast-charging delivers its potency.
John Aker, president and chief technology officer of Aker Wade Power Technologies (http://www.akerwade.com)), told me that with the larger 36- and 48-volt batteries most commonly used in the U.S., two SBX-350 cables are required to deliver more than 320 amps of fast-charging current. With an 80-volt battery you can use one cable connector because at 320 amps you can deliver more than 30 kW of fast-charge energy. Reducing the cost of the battery coupling and cabling may make fast-charging more attractive to a wider market.
And so may eliminating the need to change out batteries. Another factor keeping users in the United States away from 80-volt lift trucks is infrastructure. In Europe the 80-volt batteries are typically removed from above by crane—not with the side extraction methods used for 36- and 48-volt batteries.
According to Blake Dickinson, head of applications engineering and customer satisfaction for AeroVironment (http://www.avinc.com)), even if you invested in a crane system it would take more time to change a battery using a crane than with a side extraction system. “With opportunity fast-charging you eliminate the need for that,” he says.
Another element that could further sweeten the deal is the use of lithium-ion batteries. While lead acid will probably remain the battery of choice for one- and two-shift operations, Aker believes heavy-use three-shift operations will eventually be the tipping point for cost justifying lithium-ion batteries in lift trucks.
“Once lithium-ion batteries hit the $10,000 point for an 80-volt 500 kW hour capacity cell, it may replace lead acid,” he says. “At $10,000 you’re about twice the cost of lead acid, but the battery will charge much faster, so you’ll only need one. For three-shift operations it makes more sense than buying two lead acid batteries and swapping them out.”
Incentives from power providers may also help. That could start happening as more lift truck dealers partner with their local energy companies to meet with their customers to show the potential savings from not only switching from gas to electric, but from old style batteries to new style batteries and to opportunity fast-charging. Power company account managers may then even offer incentives.