<div dir="ltr">The only thing that stops me from saying this is the most likely and plausible scenario is the time lag. If you finished charging an hour ago and the batteries are just sitting there, what would prompt a short in the balance leads?<div><br></div><div>Now, if you had a bunch of batteries in the box, pulled one out, went flying and left the rest of them in the box in the back of your car or wherever, sure, I could believe somebody bumping into your stuff would set things off. But just sitting there in the garage?</div><div><br></div><div>Robert, so glad the family + homestead are OK! How did your wife discover the fire? Fire alarm in the garage or something else?</div><div><br></div><div>Peter+</div></div><div class="gmail_extra"><br><div class="gmail_quote">On Mon, Jun 13, 2016 at 12:56 PM, Chris Moon via NSRCA-discussion <span dir="ltr"><<a href="mailto:nsrca-discussion@lists.nsrca.org" target="_blank">nsrca-discussion@lists.nsrca.org</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div bgcolor="#FFFFFF" text="#000000">
<p>Glad everyone is ok there Robert.</p>
<p>I have handled and dissected hundreds of different packs during
my time in business, evaluating samples etc and I can say with
certainty the weakest link in our batteries are the balance leads
and their connections to the individual cells. These are very thin
wires that typically are spot soldered to tiny tabs on the cells
and crimped into tiny pin connectors. Insulation of the balance
wires inside a pack is usually a thin piece of cellophane looking
tape.There is little to no strain relief for the wires and we
handle and flex them every time they are charged. I have seen many
break off and touch others creating sparks and possibly could have
lead to fires if they were pressed together long enough. I would
bet this is what happened to Robert's pack. The batteries
themselves must pass through pretty rigorous testing including
being crushed with a metal blade without catching on fire before
they will be transported from China. These testing documents
accompany every large battery shipment so it is highly unlikely
one would spontaneously combust. With an older pack, it most
definitely sounds like an internal short of balance leads.<br>
</p>
<p>Chris</p><div><div class="h5">
<p><br>
</p>
<p><br>
</p>
<div>On 6/13/2016 11:15 AM, Robert Green via
NSRCA-discussion wrote:<br>
</div>
</div></div><blockquote type="cite"><div><div class="h5">
<div>
<p class="MsoNormal"><font face="Arial" color="navy" size="2"><span style="font-size:10.0pt;font-family:Arial;color:navy"><u></u> <u></u></span></font></p>
<p class="MsoNormal"><font face="Arial" color="navy" size="2"><span style="font-size:10.0pt;font-family:Arial;color:navy">Hey guys wanted to
let you know about an
incident I had over the weekend that caused some high
concern. I flew
four flights yesterday, then returned home. I thought I
would go back out
later and fly three more, so I charged three more
batteries. The three
batteries on was planning on using, were flown the
previous day, and were not
overly discharged. I took my kids to the movies as my
wife did not want
to go, and that turned out to be the best thing for the
family. One of my
2014 packs decided that it no longer wanted to live and
decided to catch fire
all by itself. I have always thought that the best time
for these to
catch fire, would be during the charge cycle. This
incident happened
almost an hour after charging the pack. Keep in mind that
after I charged
the pack, there were immediately put into my flight box
for storage until I got
back from the movies. After I took them off the charger,
the batteries
did not see warm in any way, cool to the touch. I have
had these
batteries for two and as far as I can remember - they
where not damaged in any
way. Due to my wifes' heroic action, the house did not
catch on fire like
my toolbox did. She brought them out to the drive way
water on them to
kill the flames. I have been pretty cavalier with packs,
leaving them out
once they are charged and not putting them in something
safe for
storage....those days are done. If this can happen to a
battery sitting
with a stored charge, I will not longer leave my house or
family
unprotected. <u></u><u></u></span></font></p>
<p class="MsoNormal"><font face="Arial" color="navy" size="2"><span style="font-size:10.0pt;font-family:Arial;color:navy"><u></u> <u></u></span></font></p>
<p class="MsoNormal"><font face="Arial" color="navy" size="2"><span style="font-size:10.0pt;font-family:Arial;color:navy">I bought a safe
yesterday, but apparently
that may not be the best thing for them either as the
battery give off a gas
and they need to breathe. In other words if you left them
in a safe you
may be creating a bomb scenario. What I did was - several
years ago, I
bought a metal ammo case. I removed 3/4 of the rubber
around the case
allowing for the exchange of air to occur.<u></u><u></u></span></font></p>
<p class="MsoNormal"><font face="Arial" color="navy" size="2"><span style="font-size:10.0pt;font-family:Arial;color:navy"><u></u> <u></u></span></font></p>
<p class="MsoNormal"><font face="Arial" color="navy" size="2"><span style="font-size:10.0pt;font-family:Arial;color:navy">If any one has any
other creative ideas on
how they store there lipos, please contribute to this
thread as I think it is
important as a community that we spread the message that
this technology which
has been proven to be safe for the most part also can be
dangerous.<u></u><u></u></span></font></p>
<p class="MsoNormal"><font face="Arial" color="navy" size="2"><span style="font-size:10.0pt;font-family:Arial;color:navy"><u></u> <u></u></span></font></p>
<p class="MsoNormal"><font face="Arial" color="navy" size="2"><span style="font-size:10.0pt;font-family:Arial;color:navy">thanks,<u></u><u></u></span></font></p>
<p class="MsoNormal"><font face="Arial" color="navy" size="2"><span style="font-size:10.0pt;font-family:Arial;color:navy"><u></u> <u></u></span></font></p>
<p class="MsoNormal"><font face="Arial" color="navy" size="2"><span style="font-size:10.0pt;font-family:Arial;color:navy"><u></u> <u></u></span></font></p>
<p class="MsoNormal"><font face="Arial" color="navy" size="2"><span style="font-size:10.0pt;font-family:Arial;color:navy">Robert<u></u><u></u></span></font></p>
</div>
<br>
<fieldset></fieldset>
<br>
</div></div><span class=""><pre>_______________________________________________
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