The presumably lab126 written script in post #1 above will keep the KOA2 battery charge between 65% and 70%. I had hoped that
Code:
echo 0 > /sys/class/power_supply/max77796-charger/charging
would turn charging off but continue to supply power to run the kindle. Unfortunately, the kindle begins running off the battery.
I have not found a way to do anything similar on the Voyage.