UPDATE: AMAZON ( and now most other major retailers)BANS SALE OF HOVER BOARDS DUE TO MOUNTING CONCERNS OVER SAFETY and WILL REFUND PURCHASE PRICE
(# make claim if over £100 against credit card company cite Section75 Consumer Credit Act. They are jointly liable, BUT SADLY NOT IF YOU PAID VIA PAYPAL).
THE RETAIL OMBUSDSMAN HAS CALLED FOR ALL HOVERBOARDS TO BE SCRAPPED - ELECTRICAL PLUG NOT UK COMPLIANT AS UNFUSED AND NOT PROTECTED. DANGER OF FIRE.
UPDATE: A setback to Hover boards being one of the most popular Christmas presents given this year as Amazon have today (Dec 15) announced they are banning them from Amazon on safety grounds, AND HAVE NOW OFFERED FULL REFUNDS to anyone buying a hoverboard. after a number of them burst into flames whilst being electrically charged. - hoverboards gained most attention by repeatedly blowing up! Incidents of fires have been reported when the hoverboards were being electrically recharged.
According to Jay Whitacre, professor, Materials Science and Engineering at Carnegie Mellon University, the cause of the fires is the quality of the batteries used to drive power the self balancing scooters.
Expensive high-end models are usually equipped with reliable and safe batteries, while the power sources in cheaper models present a much higher combustion risk to their owners.
Hoverboards with cheap li-ion batteries could catch fire due to a number of reasons, such as the board on running at its top speed and then possibly hits something.
As Whitacre explains the alignment between the anode and cathode in the cheaper battery might not be correct. The cathode and anode are at the two different end of the battery, and in between them lays the separator, which keeps them apart. But in the case of cheaper batteries, the separator could become punctured, resulting in a short circuit.
"If there is an inherent defect in the cell, it will go off at some point. Small defects in the manufacturing or materials stream lead to the plus/minus sides of the batteries being shorted with each other after a small amount of use. When this happens, especially when the batteries are charged, a lot of heat is generated inside the cells and this leads to electrolyte boiling, the rupture of the cell casing, and then a significant fire," explains Whitacre.
He further adds that li-ion battery has highly flammable electrolytes and when they come in contact of air, they burn quickly. In such situations cathode materials becomes additional source of oxygen to feed the fire even more.
Apart from the battery, a defective charger also has a role in fires, at least in some cases. He adds, "If there is not proper protection to the cells, and if the charger is defective, the cells can be severely overcharged. In cases of severe overcharge, even perfectly made cells will eventually fail, though a fire is not always the outcome in this case. The cell may just pop its gas vent and dry out."
Readers will recall the new Boeing Dreamliner suffered a series of setbacks shortly after its debut. the faults traced back to exploding Li-ion [lithium-ion] batteries. The Highways Act 1835 also bans the use of such devices on the highway or pavement......
Source IBTIMES, Wired, AFP,
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