Quote:
Originally Posted by simplechamp
I've seen a few threads around discussing that very thing. I thought BrianG had ordered a bunch of high-wattage resistors at one point to build a test rig, but not sure how that panned out....
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It really didn't pan out. Testing methodology wold have been too arbitrary (but MUCH better than any butt-dyno testing on these reviews TBH) to be of any viable use. I did do a small 10A version, and it worked, but needed constant manual adjustment to maintain a consistent current depending on the cell's IR, which does change over the cycle. What is needed is a true constant-current system that can be computer controlled for continuous testing and repetitive burst testing, which would compensate for dropping battery voltages.
And, at higher pack voltages, testing on a bench creates a LOT of heat!!! After calculating the thermal load, I would need a HUGE heatsink; something like a 400ft^2 heatsink and that's with forced airflow. 6s @ 200A is almost 4500w. Any idea how much heat that is? Believe me, my small 10A test rig on 3s generated a substantial amount of heat.
Then, as the BigSquid shootout proved, people will always complain (not targeting you Neil) that testing procedures weren't right. And getting everyone to agree would be impossible. And even if a procedure was finalized, it would be too complex for Joe Sixpack to comprehend, and would just end up getting whatever pack had the flashiest label (or best advertising).