Originally Posted by
greywolf74
Could you explain a bit more here? Im not sure I understand what you are saying exactly. Im also not familiar with the rA nomenclature. All of the packs I test are brand new and Ive recently started testing identical packs to make sure that results for a given brand/model of LiPo are within a certain tolerance. So far the duplicates have been very very similar to the original packs. Please expand on the diminishing returns and why you only charge at 40A now. Im intrigued.
rA = Relative Amps which is simply the C rating times the Capacity where a 100C - 5000mAh pack = 100C x 5Ah = 500rA
Generally most brands are fairly accurate with their rA ratings, the only brand I know which is known to overstate their rA is MaxAmps, more info here:
https://www.rcgroups.com/forums/show...0#post42146361
Early on when LiPo's were first introduced they were typically 20C packs and that rating slowly improved to the point where they have peaked to around 150C in general.... if you have a true 150C pack then it can easily handle 40A charge rate without breaking a sweat and if you cycle the battery then you will get the lowest possible IR and highest respective rA regardless of the brand you buy.
The diminishing return is two packs side by side with identical rA spec but the budget brand pack may not perform exactly as well as the name brand in similar fashion to the MaxAmps thread I linked above... at that point it's just wasting money to buy the more expensive brand when you get nearly identical performance with the budget brand.
For stock racing, I won't race a pack unless both cells are below 1m
Ω and there are plenty of budget brand batteries offering this level of performance, though they are mostly rated for 2C charge rates, if you are nervous and want peace of mind charging 40A then you can't go wrong with the Trinity White Carbon series, more info here:
https://www.youtube.com/watch?v=blWFtoiqEaE
I mostly run mod now and only care if the IR goes farther than 2mΩ apart where I will race pack up to 7mΩ for mod before I retire a pack, more info here:
https://www.rcgroups.com/forums/show...0#post43510433