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<DIV>Scott, like you, my TP5300s (4P) configuration have lasted into my 3rd
season flying electric. Yep, they are tired but will still pull my plane
vertical as far as I need, just not quite as much gusto. All my other
batteries are 1P configurations but I have not seen that show significantly
better or worse balancing challenges. I agree, the 1P configuration would
make it easier to detect a single cell developing higher IR.</DIV>
<DIV> </DIV>
<DIV>I have one FP5350 (2 5S packs) as well as 2 TrueRC 5000 mah packs (each 2
5S packs). The FPs have been solid with about 75 flights, no issues,
pretty easy to balance while charging. The 2 TrueRC packs need a little
more balancing during charge but everything finishes out fine. They have
less than 30 flights each.</DIV>
<DIV> </DIV>
<DIV>I did check one of the TrueRC packs on Jim's Cellpro and all 10 cells were
in the 3.5 milli ohm range, one cell was slightly higher at about 4 if I
remember correctly. The new Cellpro 10s is interesting and there is a
very good review and subsequent discussion about it on RC Groups.</DIV>
<DIV> </DIV>
<DIV>Don</DIV>
<DIV> </DIV>
<DIV> </DIV>
<DIV> </DIV>
<DIV>
<DIV>In a message dated 9/17/2008 9:05:48 P.M. Pacific Daylight Time,
scottcov@comcast.net writes:</DIV>
<BLOCKQUOTE
style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: blue 2px solid"><FONT
style="BACKGROUND-COLOR: transparent" face=Arial color=#000000 size=2>
<DIV><SPAN class=279212203-18092008><FONT face=Arial size=2>Hey Electric
Guys,</FONT></SPAN></DIV>
<DIV><SPAN class=279212203-18092008><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=279212203-18092008><FONT face=Arial size=2>I'd be interested
in what LiPo battery configuration you are using.. 5S2P, 5S4P, 5S1P... other.
Why?.. read on. I believe the less "P" you have in the battery the easier to
balance and possibly the longer life you will get due to better cell balancing
before charging. I have recently converted to a new cell by TP, some of you
saw this at the Hollister contest. The 5S2P, 5200 pack, is working great. Jim
Oddino and I checked the internal cell resistance, which was around
3milli-ohms (if I recall correctly). This battery puts out 156A burst, the
older 5s4p, 5300 pack put out 109A burst. My thinking is this, the lower "P"
pack you have the easier to keep the battery in balance. If you have a 4p
pack, any one of the 4p cells can degrade over time, causing the 4p 'bank' to
not supply as much sustained current - causing the whole battery to be weaker.
Jim and I played with a Cellpro 10S charger, and I think we concluded that it
would be difficult for any charger to determine if any one cell in
a 4p bank was going bad (you can only monitor the bank IR, not the
individual cell within the bank). However, if you had a 1p 10S pack, you could
easily tell if the cell was gaining resistance as it aged. On a 2p pack, the
resistance CHANGE may not show up as easily as a 1p pack but much easier than
a 4p pack. We are trying to determine here when a 5S pack is getting weak
(yes, we can see as we fly - but if we could determine as it happens, perhaps
we can correct this by charging differently). Jim O mentions he has not seen a
battery with as low of internal resistance readings as the new TP pack, which
equates to more power, less heat in use, and I hope longer life. I will
mention here that my 5300, 5s4p packs have lasted 2-3 years and many,
many flights, but they are getting old.. and the new packs may last
3-4 years.. they are also around $250 each.. a reduction in price from the
5s4p packs. I believe even newer technology will soon show us a 10s1p
pack from TP - and some may have this now from other
manufacturers.</FONT></SPAN></DIV>
<DIV><SPAN class=279212203-18092008><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=279212203-18092008><FONT face=Arial size=2>I'd be interested
in your opinions on this topic.</FONT></SPAN></DIV>
<DIV><SPAN class=279212203-18092008><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=279212203-18092008><FONT face=Arial
size=2>Scott</FONT></SPAN></DIV>
<DIV><SPAN class=279212203-18092008><FONT face=Arial
size=2></FONT></SPAN> </DIV><BR><BR>_______________________________________________<BR>NSRCA-dist7
mailing
list<BR>NSRCA-dist7@lists.nsrca.org<BR>http://lists.nsrca.org/mailman/listinfo/nsrca-dist7<BR></FONT></BLOCKQUOTE></DIV></FONT><BR><BR><BR><DIV><FONT style="color: black; font: normal 10pt ARIAL, SAN-SERIF;"><HR style="MARGIN-TOP: 10px">Psssst...Have you heard the news? <A title="http://www.stylelist.com/trends?ncid=aolsty00050000000014" href="http://www.stylelist.com/trends?ncid=aolsty00050000000014" target="_blank">There's a new fashion blog, plus the latest fall trends and hair styles at StyleList.com</A>.</FONT></DIV></BODY></HTML>