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Buying into lithium-ion19th of May 2015
Lithium-ion batteries are among the latest products to hit the traditionally slow-moving battery market. But are cleaning machine companies - and their customers – buying into the new battery technologies?
Lithium-ion technology has revolutionised the battery industry since it was introduced in the 1970s. Rechargeable lithium-ion batteries are now commonly found in laptops, tablets and mobile phones. They are also a popular choice for power tools and electric vehicles due to their low weight and high energy density. In recent years, too, there has been an increasing trend for cleaning machine manufacturers to use lithium-ion batteries.
Battery Supplies offers many products including open lead-acid, AGM, gel, pure-lead and lithium-ion. The company also supplies lithium iron phosphate (LiFePO4) batteries, which are lithium-ion rechargeable batteries for high power applications. All these products have a place according to the company’s Alexander De Soete.
He says the main advantages of lithium-ion batteries are their fast charging capabilities and their long life cycle. “They also allow for intermediate charges and are maintenance-free,” he said. “The main disadvantage, however, is their high price.”
According to de Soete, professional users quickly see the benefits of lithium-ion and are convinced by the total cost of ownership and return on investment argument. “If a battery is required for heavy professional use, then lithium-ion technology is probably worth the investment,” he said. “For someone who wants to use a cleaning machine on a more occasional basis, the choice is more difficult.”
He says pure lead technology has an enduring appeal in the cleaning sector. “Pure lead also has the advantage of fast charging and intermediate charging, and like lithium-ion it is maintenance free,” he said. “Pure lead batteries have a shorter life than lithium-ion – but they cost less.”
And gel batteries are still playing an important role in the cleaning sector according to de Soete. “They are reliable and maintenance-free and they offer good cycling at an acceptable price,” he said. “The fact that lead can be recycled also means the batteries are worth money if they are returned to the supplier.”
Trojan Battery Company has no imminent plans to launch a lithium-ion product according to director of global technical services Vicki Hall. “The flooded battery is standard in the cleaning industry, though flooded batteries gas more than AGM batteries,” she said. “So there has been a movement towards a safer solution for populated environments.”
Trojan is also looking into the lithium-ion side of the battery business. “We would be remiss if we weren’t carrying out any R&D work in that area,” said Hall. “There are various types of lithium-ion technology and we have a partner carrying out some developmental work for us. But any launch is years away and it is always going to be a niche application because lithium-ion is just too expensive.”
She says there are further disadvantages to lithium-ion technology besides its high price. “Lithium-ion batteries can short out in some circumstances and create a fire risk,” she said. “They are also hard to recycle, and you have to redesign your machinery line in order to accommodate a different kind of battery.
“Personally I have a hard time believing that someone is going to pay four or five times as much for a lithium-ion battery. We don’t see it happening any time soon and it is never going to be mainstream technology in floor care.”
Diversey Care agrees that the newer battery technologies are not particularly relevant to the cleaning sector. The company promotes the use of gel batteries to its customers according to global Taski machine portfolio manager Laurent Ryssen. “This is our first offer because gel batteries guarantee a high level of safety,” he said. “Next we offer wet batteries and AGM options.”
Lithium-ion batteries are not an option on Diversey machines. “It is true they offer a higher number of cycles, fast-charging advantages and are maintenance-free and lighter in weight,” admits Ryssen. “But the longer running times made possible by lithium-ion do not necessary result in a higher degree of productivity.
“The battery does not have an impact on a machine’s manoeuvrability - a machine offering a longer running time might seem to be more productive in theory, but if the machine is bigger and less manoeuvrable, the cleaning time will increase.”
According to Ryssen the battery industry has begun to evolve fairly quickly over recent years. “This is due to the fact there is increasing demand for mobile devices in the consumer market,” he said. “However, the next generation of batteries might have a name other than ‘lithium’.”
And he adds there is no ‘one size fits all’ solution in the cleaning industry. “It depends on the area to be cleaned, the level of congestion, the degree of staff rotation and whether or not staff have been trained in the maintenance of batteries,” said Ryssen. “Even if a lightweight battery appears to be a promising option, the manufacturer should avoid compromising on cleaning efficiency since the brush pressure is also linked to the weight of the machine and its batteries.”
Nilfisk-Advance uses lithium-ion batteries in some of its vacuum cleaners according to the company’s group product manager Thomas Tykskov. “The main advantage of lithium-ion batteries is they are lightweight, have a high capacity, can be charged very rapidly and can be partly charged and discharged without losing capacity,” he said. “While the main disadvantage is still cost, competition in the market is now so high that the cost of lithium-ion is going down at the same time as performance is improving.”
Besides lithium-ion, Nilfisk-Advance also uses conventional lead acid, gel and AGM batteries in its machines. “The main advantage of these technologies is that they have a good price/performance ratio and this lowers the total cost of ownership. But conventional batteries are heavy and use a lot of space, and they also have a lower usable capacity compared with other battery technologies.”
Sebastian Wein?from Kärcher says most of his company’s battery-powered machines run on lead, maintenance-free gel or AGM batteries. “For some markets or very large capacities we also use flooded lead acid batteries,” he said. “These classic batteries are more robust and better value for money. But in our newer, smaller machines we use lithium-ion.”
He feels lithium-ion batteries are the most efficient and the easiest for customers to use. “You can forget about the battery since it will have the same life as the entire machine, and the fast-charging and opportunity-charging benefits are really convenient for the user.”
He feels that the market share of lithium-ion will increase despite its disadvantages. “Besides the higher price, an additional electronic control is needed with lithium-ion batteries to prevent the risk of overheating,” he said.
“Flooded lead acid will disappear and be replaced by the gel and AGM battery,” he added. “This evolution has been taking place over a number of years.”
Truvox has adopted lithium-ion technology due to its fast-charging and longer life benefits says sales and marketing director Gordon McVean. “We believe the advantages of lithium-ion batteries in terms of flexibility and productivity for the cleaning team are compelling,” he said. “And the fact that self-discharge with lithium-ion batteries is low means that battery charging can be timed to fit in with the cleaning regime rather than the other way around.”
He cites the low maintenance of lithium-ion batteries as another important benefit. “These advantages come at a premium compared with other types of battery, but the cost is outweighed by the benefits.”
According to McVean, battery technology is advancing all the time as manufacturers seek to find greener alternatives to fossil fuels. “While this is not a driver for the cleaning industry we will benefit from these advances and for now, lithium-ion seems to offer the greatest potential.
“However, conventional batteries will still have their supporters on cost grounds. Users need to weigh the cost savings of using conventional batteries against the charging flexibility and low-maintenance advantages to be gained from using superior technologies such as lithium-ion.”