I want to periodically log the battery level in percent. I am only concerned with obtaining the actual battery level, not with graphing it. I have found the APIs to register an intent to receive Intent.ACTION_BATTERY_CHANGED, using BatteryManager.EXTRA_LEVEL and BatteryManager.EXTRA_SCALE.
However, my problem is, this only gives me increments of 10%, which is not fine-grained enough. I have the SystemPanel App from the Android Market, and it plots percentage versus time on a much finer scale, so I know it is possible, but in all my searching nobody seems to address how I can get this higher resolution.
This question appears to point to another project that accomplishes this, but it is not obvious how it accomplishes this: Creating a graph similar to Battery usage in Gingerbread