Battery Life

[buzzbomb33]

I got my 130S a month ago and conditioned the LiIon battery. I put it aside for a week and then it would not turn on until I charged it. Is this normal? I opened it up and found a 920 mAHr battery. Fully charged, 4.20 Volts, it discharges at a rate of about 0.72 mAmps to keep the memory alive (not map memory) which implies over 1000 hours discharge before the battery gets anywhere near 3.7 or so Volts. So why did it not allow me to go on battery power after about 168 hours of idleness? It was kept at 70 ?F. Any ideas? The battery seems good, i.e. it runs the TomTom for over 2.5 hours at a current draw of about 310 mA (day colors) or 220 mA (night colors).
Sincerely, Buzz