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<DIV><SPAN class=043255318-18082006><FONT face=Arial color=#0000ff
size=2><<<<So you were charging at 5C with a standard 2-wire to the
battery charger? Please be careful, my
friend.>>>></FONT></SPAN></DIV>
<DIV><SPAN class=043255318-18082006><FONT face=Arial color=#0000ff
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=043255318-18082006><FONT face=Arial color=#0000ff size=2>Yup,
Deano. Like I said, I'm not advocating that everybody do this.
My principle reason for doing the experiment was to determine if there was a
threshold for generating excessive heat within the pack, which did not manifest
itself. The charging was done in an area 50 feet from everything to insure
safety.</FONT></SPAN></DIV>
<DIV><SPAN class=043255318-18082006><FONT face=Arial color=#0000ff
size=2>G.</FONT> </SPAN></DIV></DIV>
<BLOCKQUOTE
style="PADDING-RIGHT: 0px; PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #000000 2px solid; MARGIN-RIGHT: 0px">
<DIV style="FONT: 10pt arial">----- Original Message ----- </DIV>
<DIV
style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: black"><B>From:</B>
<A title=d.pappas@kodeos.com href="mailto:d.pappas@kodeos.com">Dean Pappas</A>
</DIV>
<DIV style="FONT: 10pt arial"><B>To:</B> <A
title=nsrca-discussion@lists.nsrca.org
href="mailto:nsrca-discussion@lists.nsrca.org">NSRCA Mailing List</A> </DIV>
<DIV style="FONT: 10pt arial"><B>Sent:</B> Friday, August 18, 2006 2:59
PM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> Re: [NSRCA-discussion]
charging</DIV>
<DIV><BR></DIV>
<DIV><SPAN class=043255318-18082006><FONT face=Arial color=#0000ff size=2>Hi
Georgie,</FONT></SPAN></DIV>
<DIV><SPAN class=043255318-18082006><FONT face=Arial color=#0000ff size=2>What
I remember the guys at that seminar said was something more
like:</FONT></SPAN></DIV>
<DIV><SPAN class=043255318-18082006><FONT face=Arial color=#0000ff size=2>If
and only if:</FONT></SPAN></DIV>
<DIV><SPAN class=043255318-18082006><FONT face=Arial color=#0000ff size=2>1)
your charger balances continually and terminates charge if at any point it
cannot maintain balance as the charge progresses,</FONT></SPAN></DIV>
<DIV><SPAN class=043255318-18082006><FONT face=Arial color=#0000ff size=2>2)
your battery is a high charge/discharge rate cell ( 15C or 20C
rated)</FONT></SPAN></DIV>
<DIV><SPAN class=043255318-18082006><FONT face=Arial color=#0000ff size=2>3)
your charger terminates if for any reason any one cell hits
4.2V</FONT></SPAN></DIV>
<DIV><SPAN class=043255318-18082006><FONT face=Arial color=#0000ff size=2>then
you can charge at up to 3C</FONT></SPAN></DIV>
<DIV><SPAN class=043255318-18082006><FONT face=Arial color=#0000ff size=2>Of
course, the charger they were selling was built to satisfy #1 and
#3. </FONT></SPAN></DIV>
<DIV><SPAN class=043255318-18082006><FONT face=Arial color=#0000ff
size=2>Thunder-Power does something similar with a two-component
system. </FONT></SPAN></DIV>
<DIV><SPAN class=043255318-18082006><FONT face=Arial color=#0000ff
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=043255318-18082006><FONT face=Arial color=#0000ff size=2>So
you were charging at 5C with a standard 2-wire to the battery charger? Please
be careful, my friend.</FONT></SPAN></DIV>
<DIV> </DIV>
<P><FONT face="Times New Roman">Dean Pappas</FONT> <BR><FONT
face="Times New Roman">Sr. Design Engineer</FONT> <BR><FONT
face="Times New Roman">Kodeos Communications</FONT> <BR><FONT
face="Times New Roman">111 Corporate Blvd.</FONT> <BR><FONT
face="Times New Roman">South Plainfield, N.J. 07080</FONT> <BR><FONT
face="Times New Roman">(908) 222-7817 phone</FONT> <BR><FONT
face="Times New Roman">(908) 222-2392 fax</FONT> <BR><FONT
face="Times New Roman">d.pappas@kodeos.com</FONT> </P>
<BLOCKQUOTE dir=ltr style="MARGIN-RIGHT: 0px">
<DIV class=OutlookMessageHeader dir=ltr align=left><FONT face=Tahoma
size=2>-----Original Message-----<BR><B>From:</B>
nsrca-discussion-bounces@lists.nsrca.org
[mailto:nsrca-discussion-bounces@lists.nsrca.org]<B>On Behalf Of </B>george
w. kennie<BR><B>Sent:</B> Friday, August 18, 2006 2:00 PM<BR><B>To:</B>
NSRCA Mailing List<BR><B>Subject:</B> [NSRCA-discussion]
charging<BR><BR></FONT></DIV>
<DIV><FONT face=Arial size=2>This is just an FYI based on my
experience.</FONT></DIV>
<DIV><FONT face=Arial size=2>At the WRAM Show I attended a seminar by the
Kokam Battery guys and was advised that it would be completely
safe to charge my Lithium Poly batteries at a rate of 3C if one was using
one of their Balance Pro Chargers. Well, needless to say, I didn't purchase
one of their chargers, however, after hearing about several others who
were charging at 3C I decided that I would try the 3C rate and find out what
my experience would be like.</FONT></DIV>
<DIV><FONT face=Arial size=2>I have some small packs for foamies so I
decided to try one of them expecting to find some negative result, but the
opposite seemed to be the case. </FONT></DIV>
<DIV><FONT face=Arial size=2>A couple of weeks ago I attended a contest
where I was shooting my mouth off about how I had been charging at 3C and
was brought up short by one of those listening and advised that charging at
this rate would cause the batteries to overheat, to which I responded rather
emphatically that my batteries were remaining cool. This particular
gentleman became rather insensed and insistant that he knew for a fact that
the heat build-up would be destructive to the health of the batteries.
The gentleman walked away with a look of disgust and I felt bad that I had
come across so forcefully (happens too often).</FONT></DIV>
<DIV><FONT face=Arial size=2>Well, the gist of all this is that this A.M. I
went to the flying field and informed all in attendance that I was
intending to perform and experiment in which I would charge a Lithium
Poly pack in 12 minutes at a rate of 5C and we would see what would happen,
I being ready to sacrifice the pack if that indeed took place. Well, in 12
minutes exactly, the charger shut down and indicated that charge completion
had occurred. I immediately disconnected the pack and ran to the rest of the
group in attendance and had everybody feel the temperature of the pack and
to everyone's amazement the pack was not even luke warm. I subsequently flew
the pack and thought that I got a little longer flight time than I
normally do (probably all in my head). Now, these packs have never been
balanced, and in fact have no balance plugs.</FONT> </DIV>
<DIV><FONT face=Arial size=2>So, am I recommending that everyone start
charging at 5C? Definitely not ! I'm certainly no battery guru, but I
am of the opinion that there may be a lot more for us to learn about the
current technology and I'm certain the developments in the near future will
surprise many (including me).</FONT></DIV>
<DIV><FONT face=Arial size=2>Georgie</FONT></DIV></BLOCKQUOTE>
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