Like most manufacturing companies, many of today’s warehouses and distribution centers operate three shifts per day, seven days a week. Some rely on large vehicle fleets with dozens of forklifts, burden carriers and stock chasers to carry and tow pallets, packages and parts. Depending on the size of the operation, small adjustments can deliver big improvements in operational efficiency. Converting their fleets from conventional flooded lead acid batteries to virtually maintenance-free NexSys® Thin Plate Pure Lead (TPPL) batteries offers material handling facilities a proven prospect for improvement.
In September 2013, EnerSys® helped a premium automotive manufacturer embark on an efficiency improvement program at the automaker’s warehouse distribution center in the Lehigh Valley region of Pennsylvania. The facility fulfills orders for new and replacement parts using a fleet of electric Taylor-Dunn® burden carriers operating on a 20-hour shift schedule. Taylor-Dunn® stock chasers are efficient vehicles that can carry loads as high as 1,000 lbs. and tow up to 5,000 lbs.
The warehouse efficiency program included a gradual fleet conversion, beginning with the replacement of 40 burden carriers powered by flooded lead acid batteries with 20 new burden carriers powered by NexSys® TPPL batteries and a new fast charge system.
Unlike conventional flooded lead acid batteries, NexSys® batteries from EnerSys® do not require periodic watering and are virtually maintenance-free. Their advanced lead acid plates are low impedance, highly corrosion-resistant thin plate grids manufactured from 99 percent pure lead. The plates deliver high electrolyte absorption and are compressed before being inserted into the battery case for extreme vibration resistance.
The combined result is a battery that offers optimized cycling plus opportunity and fast charging capabilities that conventional lead acid batteries – AGM, gel or flooded – cannot.
In fact, TPPL batteries can handle high charge rates, making them ideal for multi-shift operations. For comparison, flooded lead acid batteries typically charge at a rate of 16 percent of the battery’s 6-hour rated capacity, and usually take 8-10 hours to fully charge. NexSys® batteries charge at up to 70 percent of the battery’s 6-hour rated capacity, requiring just a little over an hour to be fully recharged. The ability to charge at such high rates at any time during the shift-day enables the elimination of battery changing, even in some three-shift applications. The associated reduction in maintenance can be significant.
For the automaker’s warehouse facility, powering the 20 new burden carriers with NexSys® TPPL batteries and the new NexSys® battery fast charge system allowed the batteries to be charged during operator lunches and breaks, rather than the 12-hour per shift charge required by their previous flooded batteries.
As the warehouse efficiency program began, the facility’s goal was to ensure that the batteries maintained at least a 40 percent State of Charge (SOC). Thanks to their opportunity charging capabilities, NexSys® batteries consistently achieved a 70 percent SOC. As a result, EnerSys® was able to help the distribution center eliminate the second burden carrier per shift, reducing the fleet by 50 percent, as intended. A corresponding drop in facility maintenance demands and cross-plant traffic has also followed, further improving overall warehouse efficiency.
