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Old March 5th 05, 02:32 PM
scooter
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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