The return of 50 degree mornings near Seattle is starting to affect my morning RR readings, which have stayed above 62 this summer despite over 90k miles on the odometer. Well, I pushed my limits once last week and confirmed that I'm down to about 2 miles left in the turtle, with 33.2 Ah reported capacity. This is the second time ever that MR BEAN has been driven to the point of shutdown (1.5 miles short of home). The battery resting voltage was 306.5V at 40 degrees C (104 F), and a wide disparity of 0.63 Volts between the highest and lowest cell surfaced. Cell #8 was 3.70V and cell #19 was 3.07V. State of charge in this condition was reported at 4%. Contributing factors were leaving home with a partial charge and being only a week into a new set of tires (Continentals up front and Don's $45 specials out back), with tire pressures still down low at the installer's 32 psi.
After a full recharge and overnight balancing, the high and low cells were within a coupla hundredths of a volt, RR was 54 miles, and then I aired 'em up to 42 psi.
I'm noticing after some testing that the displayed penalty for heater use is growing proportionately higher, with the RR settling down at 34 after a minute of full heat. I presume the software is applying a fixed heat load to the smaller battery capacity, yielding a proportionately larger range impact (37%).
I was hoping to push this battery to 100,000 miles of service (there's always hope for a sick cell to win a warrantied pack replacement), but after I get a few other round tuits cleared away, the time may come to replace this battery with the low mileage junkyard spare I picked up early this year. Then the original pack could be used as a range trailer or the cells parted out for use in a conversion and i-MiEV spares for other high-mileage pack rebuilds as they fall out of warranty.
As I drove the hobby cars more during the dry season, MR BEAN's annual mileage rate fell from 19k to 17k, but the return of rainy weather will crank that back up, and with any luck (and judicious heater use), MR BEAN will achieve 100k miles by the end of February.
I've updated my entry on the i-MiEV mileage spreadsheet and encourage others to do the same. https://docs.google.com/spreadsheets/d/ ... edit#gid=0