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Old 18-12-2014
SlowOne SlowOne is offline
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Join Date: Oct 2007
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It's well documented that the manufacturing process for making LiPos is always going to end in some failures however careful people are with their LiPo ownership regimes. Puffing of LiPos is the first sign that those manufacturing issues and the growth of dendrites has come to a pack near you, and said pack should be gracefully retired via a bucket of salty water.

I've sat next to two LiPo fires and can comment as follows. In both cases the settings of the chargers were suspect, down to user error most likely. A sack is essential as it stops the hot debris spreading further afield and causing more mayhem. The achilles heel of the LiPo sack is the velcro, which melts and allows the tops to spring open allowing gas and flames to escape. The kevlar liners do their job, it's the velcro that allows escapes.

The 'box-style' LiPo sacks are next to useless as they have too many openings and the path of the hot gases is guaranteed to melt the velcro and the box pops open. The other fire was in a flat sack with the LiPo pushed to the bottom and the flap firmly closed. That did eventually pop open, but the delay was long enough for the bucket of sand to be on its way and the damage to surroundings was much less than the fire in the 'box'.

As for his 'procedural breakdown of how to respond to an RC [sic] fire' it is well known and proven effective. DO NOT try to get at it or anywhere near it with exposed flesh; cover the fire in sand. Never use any fire extinguisher as they don't work and water ones will only add the the problem - hot, water to steam, oxygen to feed fire, etc.

At 12th Nationals we have two, 2-gallon buckets of (fine, dried) sand in the pit area and one at the track area. As soon as a fire starts the bucket is rushed to the scene and its contents dumped on the LiPo. Once the sand coverage is enough to stop all egress of flames, smoke and debris, the area is left for at least 30 minutes until it is cleared up. Once 'dug out' the offending LiPo is left outside for at least three hours.

That the marshall is carrying the burning car and there was obviously no sand available is a huge minus for the organisers, as well as a common sense failure!

If LiPos have to go then we are all going to be miserable. These things go pop is all sorts of appliances, so is he really going to do without his 'phone, iPad, laptop and the countless other devices that use LiPos as back-up batteries? No. RC LiPos hold a lot more energy than the average 'domestic' LiPo, so when they go pop they do so with more vigour.

It's a sad article devoid of knowledge or facts and without alternatives that might make the abandonment of LiPos viable. It reflects poorly on the author as well as the sport. It is just the sort of canon fodder anyone hiring out a hall to us would need to withdraw the booking and put more pressure on the sport. Bad work...

Last edited by SlowOne; 18-12-2014 at 09:06 PM.
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