Motive power batteries: New technologies deliver benefits

•  Maximising the vehicles’ time in productive use

Challenge: When using vehicles with traditional batteries in multi-shift operations, production time is lost as discharged batteries must be exchanged. Spare batteries  incur extra cost and space requirements.

Solution: Thin Plate Pure Lead (TPPL) VRLA batteries allow vehicles to be used continuously, even in a multi-shift environment. They accept high charge rates, and allow opportunity charging during natural breaks within a shift; batteries stay within the truck, so swap-out time is eliminated.

•   Charging in situ

Challenge: Flooded cell batteries release oxy-hydrogen gas and acid vapours during charging. Therefore, they must be charged within a dedicated room with extraction capability to avoid health risks and product contamination.

Solution: Choose batteries that do not gas during charging. The cost and space of supplying an equipped charging room is avoided, as is the disruption of vehicles traversing between production, warehouse and charging areas.

•   Controlling maintenance costs

Challenge: Flooded cell batteries have a significant maintenance requirement, with a need for regular water top-ups. These are time-consuming, pose risks for operators and to the factory floor and, in larger facilities, incur substantial water bills.

Solution: More recent VRLA lead-acid types save maintenance time, risk and costs as their internal recombination processes mean that they do not require water top-ups.

•   Minimising energy costs

Challenge: Flooded lead-acid batteries require overcharging levels of 10 to 20% to generate acid mixing and minimise stratification. This adds to the facility’s energy costs and impacts its green footprint.

Solution: Battery technologies available today require lower overcharging, at typically 8 to 10%. Up to 30% energy savings can be achieved by using such batteries with suitable chargers.

•   Reducing replacement rates

Challenge: Ongoing capital costs for traditional batteries are higher than necessary because of their operational life cycle limits.

Solution: Innovative lead-acid batteries offer cost-savings through improved operating life, with expectation of 1500 – 1600 cycles at 60% Depth of Discharge (DoD) for current designs. They are suitable for use in Partial State of Charge (PSoC) applications.

•   Reducing space requirements

Challenge: Compact trucks are required for narrow aisles and other confined areas.

Solution: Plate sizes have reduced from 9mm to just 1mm thickness in some products; this allows 30% space savings compared with equivalent AGM types.

•  Cost and organisation required for battery storage

Challenge: Conventional batteries must be recharged once every six to 12 weeks during storage. Resources are required for monitoring the open circuit voltage of batteries in inventory, and boost charging when necessary.

Solution: Latest-technology lead-acid AGM batteries can be stored for up to two years at 68°F when starting from a fully-charged condition; this reduces the monitoring and boosts charging requirements and cost.

•   Minimising capital costs

Challenge: There is widespread industry interest in Li-ion batteries as a replacement for lead-acid, but one drawback of Li-ion technology is its cost.

Solution: The latest lead-acid battery technologies, while offering many technical advantages, have a cost factor of 1.4 to 1.6 compared with standard lead-acid types. By contrast, many Li-ion batteries carry a historical cost factor of 4 to 6 over lead-acid.

•   Recycling to reduce costs and environmental damage

Challenge: As all batteries have finite operating lifetimes, disposing of them responsibly with minimal environmental impact and cost is always a concern.

Solution: Against this background, Li-ion batteries present difficulties. All Li-ion types must be chemically analysed to determine whether they contain any valuable materials. Lithium iron phosphate battery recycling currently is hardly worthwhile, while with lithium cobalt oxide batteries the cobalt can be recovered and corresponds to about 10% of the new cell value. However, Li-ion recyclability is anticipated to improve.

Lead-acid batteries, however, are easily and almost completely recyclable.

•   Batteries for challenging conditions

Challenge: Batteries can be subject to harsh environments, with shock and vibration, wide temperature ranges and heavy-handed treatment.

Solution: The grain structure of the pure lead used in TPPL batteries makes the plates far less susceptible to corrosion. The batteries are resistant to harsh shock and vibration conditions due to their rugged construction and a vibration-resistant compound. They also have a wider operating temperature range than other lead-acid battery designs.

For more information about TPPL technology, please visit: http://www.discohttp://www.discovernexsys.comvernexsys.com/