I have been a bit slack with the blog this week. Last weekend, following dis-assembling pack #2, I charged all packs as per normal then used my single balancing charger to "top off" each pack. I got the job done over the weekend - way better than the 2 weeks using two chargers last time. Some packs balanced up within 3 hours, maximum was 10 hours.
All the packs took 3 Amps for over 3 hours on the full charge so overall the cell balance is looking pretty good now.
I also got to the bottom of the AH difference from Vogue display to actual.
I stupidly was assuming that the current sensor put out 2.5 volts for no current (correct), then 5V for +100A and 0V for -100A - WRONG. Upon careful reading of the specs. I realised the the sensitivity spec. 20mv/A means exactly that. 20mv/A then 200mV/10A then 2000mV/100A or +4.5V for +100A and 0.5V for -100A. Curiously when we set up a 12A current flow to calibrate the sensor, it was only 17% out - not 25%. Anyway it's now calibrated to within 200mA - the resolution of the Digital to Analogue input on the dashboard PIC micro processor.
That also means that we really did pull 14.3AH from the pack which also means that all cell pairs are pretty much OK.
So the total range for 16AH that was projected as 80km is closer to 70km under those driving conditions. That's still good - old tyres, no front end alignment yet and it was a lot of stop/start driving (137Wh/km).
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