All the better to see you with
And now to start catching up for the last two and a half years - somewhat chronologically:
To watch the batteries a little better I added a red LED digital volt meter. It's bright enough to read except in bright direct sunlight, and matches pretty well with my handheld meter. I'll get a much better read on the batteries now, and can watch them in real time. The meter updates a few times a second.
The good is that its:
-isolated power and sense pins
The bad is that it's cheap. I burnt two of them before I figured out that it can't really handle the high voltage leakage paths from the pack to ground. When I hit the accelerator, the meter goes crazy, and in a few days dies with one part burnt off the PCB. After looking at the toasted parts I figured it must be arcing from high voltage to the house ground, and probably due to the noisy voltage spikes when the controller is actively chopping the DC. A $5 isolated 12V-12V DC-DC supply on the 12V power input has fixed it, and it's still running strong two years later.