Originally Posted by Kenny_G

IR only tells us a small portion of battery performance however. What happens to the Voltage Drop under a load tells much more of a reality on a packs performance. I have a couple of packs here that have wonderful IR numbers, but when I put a real life simulation (current draw) the voltage drop is higher than some other packs that have better IR numbers.
The difference is noted on the track as well ripping on our high bite straight

Originally Posted by biz77

I have tested many current batteries. SMC is about the best there is in both IR and voltage under load. The fact they are less expensive than most other options is just icing on the cake. I'll admit some of the older SMC lines were great performers, but notorious for puffing - never saw one ignite however. This current product is solid.

Originally Posted by Roelof

Maybe I was wrong teached with my electronics education but voltage drop under load is caused by the IR. Or did you mean the voltage drop onder load over a time?