I hightly recomend Battery Monitor Widget.
Its the only app i have found that will give me a breakdown of voltage and current used / supplied. It will show the current amount of current the battery is either draining or charging. It also has the ability to graph and save the info so you can look at it later. I have mine set up to check every 60 seconds, and it records data for 24 hours.
This will let me go back and see how much the current drain was for any given minute in the past 24 hours (or longer if you want) it will also save the voltage, temp, percentage and charge / discharge state.
They have a free and paid app. After using the free app for a few days i felt it was well worth paying the creator for his time.
It works great with HTC devices but not so well with Samsung. I am back to using an EPIC and it doesnt show the current correctly when charging. But it does show the voltage and percentage.