well, it depends........... don't you just hate that term?

All the following IR values were taken with the cells at about 75 degrees using the same FMA Cellpro 10S charger. The packs were charged at 1C as a 10S set. The IR will increase as the packs are colder and decrease if they are warmer. These are my experiences and others may have different results. in other words, YMMV

For my TP 5300 V2 Prolites at 75F, somewhere around a 3 mohm per cell is typical and it is a 20C battery. I only have about 70 flights on these and the IR has increased about .4 - .5 mohm per cell average with a +- .3 mohm variance. The packs perform very well and are good steady power during flight. I notice minimal drop off toward the end of a flight and pack temps seldom exceed 110F.

I have a set of FP 5350 with less than 70 cycles on them and the IR is above 7 mohm per cell on average with as much as 2.5 mohm variance. These packs are 'done' and are the worst I have had so far. Even worse than a couple cheapo chinese packs I tried. My oldest TP 5300 5S4p packs with over 250 flights on them have an IR that is less than the FP 5350s with 70 cycles and the variance is around .5 mohm. They will still get me thru a P-09 schedule but it is pretty draggy near the end and the packs are pretty toasty.

My Hyperion G3 5000s (25C) started out around 2.1 mohm per cell with a +- .2mohm variance. After the first 1-12 cycles, they have remained basically the same. In fact, they improved slightly at around 12 cycles. These cells are pretty impressive so far. Packs will warm about 20 degrees during a typical flight.

For a 20C pack, my guess is they will be 'done' at around 6-7, maybe 8 mohm per cell maybe a little less for a 25C pack.

As the lipo batteries have improved, our expectations of them have also increased so what we considered OK a year or so ago is pretty poor performance with today's newer lipos. It will be very interesting to see what the next couple years holds for the lipo world.

I am pretty careful with my packs and hardly ever take 80% out during a flight. Typical recharge for a P-09 flight is 32-3300 mah. I am usually at 68-70A or less during a flight unless it is windy and then I might hit 73-74A for a brief period. I charge at 1C and each packs gets at least 5 easy flights on them prior to being 'put to work'. I don't know if this break in approach helps battery life, but that's the way I do it.

Woodie