http://bhlnasxdkbaoxf4gtpbhavref7l2j3bwooes77hqcacxztkindztzrad.onion/robowaifu/res/23.html
Let's say you need 400 watts for 2 hours a day then normal moving about at 100 Watts a hour with 7 hours for recharge at zero watts,
We need 2 x 400W/h + 17 x 100W/h = 800w/h + 1,700W/h = 2,500W/h per day
Some battery prices found on ebay at random.
SANYO UR18650ZTA Li-ion batteries SANYO, 11 Wh, 3000 mAh, 3.7V maximum discharge rate of these batteries is 5.8A
Total batteries needed at above rate = 2,500W/h per day/11.1W/h per battery = 225 batteries, @ $20 for ten = $450.45"
So...