Bill Daniels wrote:
"Eric Greenwell" wrote in message
...
If you are still interested in Lithium batteries for your glider,
read
this article on the cautions given model airplane users. He gives
statistics and talks about safety aspects, including ways to avoid
torching your car or your house. Here's the article:
http://rcgroups.com/forums/showthread.php?t=209187
--
Change "netto" to "net" to email me directly
Eric Greenwell
Washington State
USA
I spent a couple of days at the Academy of Model Aeronautics
Convention
which was in the Ontario, CA Convention Center a month before the SSA
convention was in the same venue. SSA had a booth there.
LiPo battery vendors were everywhere on the convention floor.
Electric R/C
helicopters and airplanes were being flown indoors all powered by
LiPo
batteries.
I asked all the vendors about the "Fire/Explosion problem" with
Lithium
Polymer batteries. They said, "Sure, if you are dumb enough to use a
charger designed for a lead acid battery." No one said there were
any
issues with the batteries IF you used the correct charger and didn't
do
something dumb like puncture a cell.
It's worth noting that the model airplane guys use Li-Po cells in
metal foil
pouches instead of hard plastic boxes because they are lighter. Any
Li-Po
battery likely to be used in a glider will be in a hard, impact
resistant
case. The real problem is that 8AH, 14.8V Li-Po packs cost about
$300.
That's likely to drop by 50% in the next year.
The only guy that claimed there was a problem was a guy in the
parking lot.
However, he was setting on a case of homebrew Nitro-Methane model
engine
fuel while puffing on a cigarette. I think his label said "Standback
&
Duck".
Bill Daniels
Having flown Li-Po batteries in all range of radio controlled
contraptions for a few years now, besides the charging risk, another is
any - even momentary short circuit.
I charge my packs with the appropriate charger in a heavy ceramic dog
dish in case anything bad happens. Over the years, I have had packs
swell (again using the correct charger) but nothing else bad or
catastrophic.
I had to throw a pack that I was working on out the back door once
while soldering a connector on and shorted the leads with the soldering
iron tip. The pack immediately caught fire - smoke and smelly bad
stuff immediately!
The prices continue to drop and there are a lot of chargers to choose
from now but I will not be putting one in my airplane to save a few
pounds. Losing the weight myself is a better option!
Scott Elhardt