Beer lovers might cringe at the thought. But Fort Sumter, S.C.-based beer distributor Yahnis Co. has strict instructions to keep brew stored in its distribution center at room temperature—70 degrees. That requirement prompted the company to swap out its 15 heat-generating internal combustion engine (ICE) lift trucks for new Toyota electric models a few years ago. A drastic move, perhaps, but banishing the ICE engines brought benefits well beyond temperature control, says Tommy Parnell, the company's operations manager. It's cut down on noise and dissipated the clouds of evil-smelling engine exhaust that hovered over the site.
Yahnis's story is not that unusual. Riding the clean-air wave, manufacturers of electric trucks have marketed their way into distribution facilities across the country. In 2001, electric vehicles accounted for 61 percent of all U.S. industrial trucks, according to Toyota Material Handling U.S.A.
Though electrics may be clean and quiet,they still require a power source—in this case, batteries. That's big, heavy-duty batteries that typically cost between $1,900 and $5,000 apiece, according to Roger Clark, vice president of sales and marketing at BatteryTest Inc. of Easton, Pa.
Yet that high price tag doesn't always guarantee that batteries receive the attention and maintenance they require. "Battery handling is one of the most overlooked areas in the DC," says Tony Amato, vice president of sales and marketing for Battery Handling Systems (BHS) of St. Louis. That can be an expensive mistake: Neglect both shortens battery life and compromises performance.
Battery basics
How do you protect that investment and keep your batteries in good working order? It starts with buying the right batteries."If a battery is too small for the truck,it won't be able to sustain the charge long enough to complete a job you want to do on a shift," says Bill Gilroy, area manager, Northeast, Mideast and Midwest for Yale Material Handling. "If it's too large, you're overpaying, getting more power than is necessary or than can be used by the truck."
Because batteries are expensive, some are tempted to buy just enough to get by. That's a temptation you should resist. "Companies often get into trouble because they don't have enough batteries per truck ," says Rick Hoff, vice president of operations for Industrial Battery Products of St. Louis. " If you don't have enough batteries, you'll be able to produce, but the potential for electric component failure is there. "For trucks that are operated a round the clock, Hoff recommends buying three batteries per truck. "For every hour you discharge," he says, "you want to have about the same amount of time to charge and then cool your battery."
The charging and cooling operations often take place in a special room set aside for battery-related tasks. Isolating the operati ons makes it easier to address fire protection and ventilation issues as well as flush out and neutralize spilled electrolyte, if necessary. These rooms typically house an array of specialized handling equipment—battery storage racks (which can reach up to six levels high), chargers, watering systems and in some cases, automatic battery changing systems. "Ba tteries weigh from 2,000 to 3,000 pounds and are filled with acid," says Amato. "The right equipment is essential to limit the handling dangers."
How a battery is changed out varies greatly from one DC to the next and from one truck to the next. Reach trucks, for instance, require handlers to roll the batteries out sideways on rollers. New automated systems are making the job easier. "The operator simply pulls the truck up to the system, opens the battery restraint, unplugs it, and the system selects the best battery and swaps it out," says Glenn Johnston, grocery and logistics specialist/national accounts manager for MTC in Temple, Texas. "The entire process takes two to three minutes and doesn't require manual handling."
That convenience carries a price tag. A sophisticated system that handles a 100-truck fleet with 200 batteries, for example, will typically run about $225,000, says Johnston. "Still, you can usually achieve payback in about two years," he says. "People like the idea, and we're seeing a lot of interest in these systems."
Once the battery is off the truck, it must be charged. "All managers overseeing lift trucks, whether they have one or 1,000, should equip their facility with a proper (and wellventilated) battery charging station," says Gilroy. Charging is typically an eight-hour process.However, new fast-charge systems are now available that can cut that time down drastically, reducing the number of batteries required for your operation. (See sidebar.)
Batteries need watering, too—but only after the recharging process is complete. "If you water a battery before a charge, you're going to have water and acid rising up over the top and acid will end up on the floor," says Hoff. "Not only that, but your capacity will be down."
How you water isn't nearly as important as simply ensuring that it gets done, but there are automated systems today that can save time and effort. An automatic system consists of an electronic control that delivers water to the battery, along with a vent cap installed on the battery cells to control the flow of water to each cell. The operator plugs the system into the battery when plugging it into the charger, and the system delivers the water and then automatically shuts down.
Even after charging and watering, a battery still may not be ready for duty. "You also want to check voltages and electrolyte specific gravities," says Ken Sanders, director of motive power engineering at East Penn Manufacturing in Lyon Station, Pa. It's important to keep batteries clean, too. "Rinse off any acid build-up to prevent it from dropping the voltage," recommends Johnston. "Also check your cables periodically."
Testing, 1-2-3
Even the most scrupulous maintenance program can't keep batteries going forever. So at least twice a year, batteries should be tested. "Batteries dropping below normal voltage can cost you a lot," says Amato. "Testing eliminates surprises," adds Clark. "If you find a failing cell and replace it, it will run you $200 to $300, much cheaper than replacing an entire battery."
Testing can be done manually or with new automated systems. These systems typically run upwards of $20,000, but ROI can be achieved within a year, says Clark. "An automated system is passive and doesn't require labor," he adds, "so you can test more often than you would manually."
When your batteries finally have reached the end of their lifespan, usually after 1,500 charge cycles, you need to look for safe, responsible ways to recycle them. That can be as simple as returning them to the dealer. "Most battery dealers will take them back and pass them on to a smelter,where the lead is removed and reused," says Amato.
To be on the safe side, ask for documentation proving that the battery has wound up in an EPA-approved smelting facility. "Your biggest concern should be where the battery is going," says Hoff. "All too often, it's sold to the local scrapyard and you don't know where it will end up."
No question today's batteries represent a giant step up the evolutionary ladder—technological advances have brought a 25-percent improvement in watt-hours per pound over the past 20 years, says Brett Wood, national product planning and marketing manager at Irvine, Calif.-based Toyota Material Handling U.S.A. But most electric truck batteries still can go for only one work shift before they need to be recharged. That means an unwelcome halt to the truck's operations in multi-shift operations.
Hard-charging DC executives don't always have patience with slow battery charging operations. So it's not surprising that companies are sprouting up to offer fast-charging technology. Available for industrial truck batteries for about four years now, fast chargers can return battery e n e r gy while the battery is still inside the truck, eliminating the need for battery changes. "Lift truck operators can use their idle time for recharging," explains Peter Michalski, director at Edison Minit-Charger of Irvine, Calif. "When a driver is on a break or taking lunch, he can hook up the battery to the fast charger without having to take the battery out. Any time the truck's not in use, the battery gets charged."
How much charge a battery receives during one of these breaks depends on how low the charge is and how hot the battery is. "Typically, a battery is only down to about an 85-percent charge by the first break of the day," says Lynda Stephens, marketing manager of Aerovironment in Monrovia, Calif. "As the day goes on, it will drop to a 40- to 50-percent charge, and will get about 25 percent back at these later breaks."
Another advantage to the fast-charge approach is that batteries don't need to be watered as often. "Fast chargers require less water, so instead of having to water the battery after each shift, you can water on a Monday and be done for the week," says Michalski.
Some proponents of traditional charging claim that fast charging leads to shorter battery life. Not true, says Stephens. "If you're running one battery per truck, as opposed to two or three, the battery will chronologically run down faster than through traditional charging," she says. "But you will still get the full amp hours (typically 1,500) out of the battery."
Another downside is the cost—around $10,000 to $15,000 per lift truck. But Michalski says that the initial ROI can be achieved within two years because with fast charging, fewer batteries and less space are needed.
Still in its early days with industrial trucks, fast-charging technology has yet to experience widespread adoption. But several large companies—Ford and Nestle, for example—have bought in. At least we know that low batteries won't be responsible for delays in filling the American public's endless appetite for cars or chocolate.
