Thread: New Product ESR / IR Meter fo Lipos
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Old Nov 13, 2010, 01:01 PM
Wayne Giles is online now
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Quote:
Originally Posted by like2fly! View Post
Mine arrived promptly. Thanks for fitting 4mm gold bullets Wayne, i wish i could solder connectors so neatly!
Just checked the ir on the cells of two packs, both are 4s 2650mAh Thunder Power Pro Power 45C, which have about 90 cycles on each, both bought early this summer on the same day and used in a 3dhs Aspera and 3dhs 51" A J Slick.
At ~21 deg c (~70 f) rounding to 1dp one pack cells are 5.8, 5.8, 5.8, 5.8
The other is 6.2, 6.2, 6.2, 6.2

Neither pack has been used for 3 weeks, both were storage charged to 3.95v on a hyperion duo and cool stored. voltage today is very well matched for the cells in both packs

Alex
That's impressive for packs which are 90 cycles old, depending on how hard you cane them of course. Perhaps TP do actually match cells on assembly. Presumably the two packs have been soaked at the same temperature for some time. A dodge I do is to rubber band them together overnight if I am comparing packs and measure again next day. Temperature is so important.
I have a pair of 6S5000 20c Turnigys which are unused and are equally perfectly matched, but they are, as yet, unused. I also have two 5S3000 20C Turnigys which are fairly unmatched in IR terms and were not matched when new.
It's interesting to look at a pack which is showing signs of deterioration; generally you find a cell which higher than the rest - a sign it is on the way out.

Wayne
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