Quote:
Originally Posted by Mike Dabrowski 2000
I did an interesting test yesterday that I believe would be able to somewhat determine the internal resistance and health of the pack.
I have a full time voltmeter on my pack.
I was idling, pack at 158V no current in or out.
I revved the engine by using MIMA assist to put the full 100A into the IMA motor. The 158V dropped to 138V under the 100A load.
This voltage drop mostly represents the packs internal resistance.
After a short burst of assist,I let it idle again and the pack settled back to ~ 156V in less than a minute.
If we had several people repeat the test, we could compare numbers and see if the test tells us anything.
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Mike, I'm interested in doing this but am wary about running pack wiring to the cabin, if I put a .5amp fuse in line with wires going up to the drivers seat area, would this cause any voltage drop without load through the wiring?
Thanks for the result, I thought that, based on Peters result that the internal resistance was less than that because I thought the car did a negative recal at 140v. I couldn't figure out how NiMh could possibly have that low of internal resistance and I hadn't seen any numbers of voltage under load so I was thinking that the car really never sent the battery anywhere near the empty end of its SOC range. This really cleared things up for me because I was really scratching my chin trying to figure out how that was possible as I figured that the battery would have to drop lower than that to get at a decent amount of useful capacity. I'm curious what it looks like at 100 amps at 20% SOC on the dash gauge. I don't have MIMA(yet), so I will not know if I'm pulling 100 amps if I do the test. Does the car ramp down the amperage when getting around 5 bars or so? It does at 3 based on the stock gauge for mine while it sits in limbo as the BCM waits for the battery to appear empty based on its criteria.
