[NSRCA-discussion] Power batteries

[Earl Haury]

I and a couple of flying buddies have flown around 2500+ E flights the last couple of years and have learned some things relevant to battery life. Like with IC, it's important to understand that any brand's life can be shortened by the way it's used. There are "good practices" with both glow and E - ignoring them can (will) be costly. There are brand choices with each also, and most find that cheapest isn't often the best value. Over the last couple of years we've flown several brands with low C (10-12), medium C (15-18), & high C (20+) ratings. A useful analogy might be to compare these to a powerful car engine with 2, 4, & 2x4 barrel carburetors. In the first case it's hard to hurt the engine and life is long, but power is limited. With the 4 barrel good power is available and the engine is relatively "safe" and long lived. With the dual quads power is awesome but the chance of blowing the engine is high and life is short. For pattern we probably want the 4 barrel (medium C) to realize the best value.

My position on "good practice" with pattern batteries is posted @ http://www.flightpowerusa.com/index.asp?page=News/open(article.asp^articleNo=441_parent=technical  so I won't repeat it here. 

My experience with the FlightPower Evo F3A packs last season was one of consistent performance, with good power from beginning to end of flight. Cycle life was quite good with packs exceeding 160 flight cycles and being suitable for competition at 140+ flights. (That gets the retail cost below $4/flight.)

I've a couple of flights on the new FlightPower Eon F3A packs which are rated 5400 mAh & 20C (They're very nearly the same same size as the Evo & 1183 grams wired for flight.) Overall performance is similar to new Evo packs with noticeably better end of flight performance. FlightPower expects the Eon packs to deliver significantly more cycles, we'll know for sure after the season.

Earl

Team Flightpower




 

----- Original Message ----- 
  From: Richard Strickland 
  To: NSRCA 
  Sent: Tuesday, February 10, 2009 11:29 AM
  Subject: [NSRCA-discussion] Power batteries


  OK, new subject: All my sets of batteries were close to the end of their useful lives this last season.  All are showing fairly high resistance values and most were noticeably down on power.  Shot. Kaput.  
  Soo.. I've got to go invest in four sets.  Tru's lighter sets enable me to make weight--but I'm not crazy about the durability with some of Orland's experience--although they have replaced bad(slightly squishy--puffed would be too strong a term) packs under warranty.  I don't know how their larger and higher rated packs hold up and they 'only' put me over a couple oz. Price is pretty good.
  The older Tanics I had actually held up the best over time--but the newer ones have not--and fairly expensive--but I drive by 'em twice a day and wave.  I had a set of Kokam 4800s and they didn't hold up well either and I think they have abandoned the larger battery market-- were/are expensive. I'm hearing Flightpower mentioned often and wonder if they have a battery guru that gives pattern guys a break.  I never really got serious about TP as at one time they had--as far as I was concerned--too many cells in their packs--but perhaps it's time to re-visit.
  We also had some of the original FMA 5000s and they weren't all that great either--but may have improved with a new cell vendor.
   
  So I'm in a bit of a quandary.  Any thoughts?  This should be interesting.
  RS


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