There’s more going on than I first realized. The battery level API returns 100, 66, or 33 for values. After my rephone has been running on a fully charged battery, and it shuts off because the battery level is too low after an hour (based on current consumption), and I plug it back in - the battery level reads ‘66’.
Furthermore, after only about 20 minutes of being plugged in, the API for this (rephone-supplied) 540mAh battery reports 100. I would expect the Linkit 2502 (the part which is in the rephone) to take a minimum of an hour to recharge a relatively discharged 540mAh battery, based on how much current it provides during charging.
One explanation could be that the rephone is shutting down too early (while the battery still has charge left); when plugged back into a power source, it doesn’t have very far to ‘top off’ the battery.
This link from the LinkitAssist 2502 page seems to indicate much lower power usage than I am seeing with my device (only the GSM entry is valid, the GPS part is not the same as the rephone xadow v2 gps part).
labs.mediatek.com/forums/posts/list/132.page
There are some additional points in this topic which refer to the charging current provided, being 0.1-0.3C in ‘pre-charging’ and ‘constant current’ being 0.5C.