[hankbear]

To eliminate the 10% drop in the first 20 minutes, just charge the battery in an external charger. I do this, since I have spares and a couple of battery chargers, and the difference is night and day. Last night I played a game that drains the battery heavily, so it was below 15%. I normally do not hook it up to a charger overnight, but did so last night because it was so low (I use it for an alarm clock, so I need it to not die overnight). I took the phone off the charger, and, within 10 minutes, the battery dropped to 91%. Now, granted, I was using it for those 10 minutes, but still! By the time I went downstairs to leave for work, it was at 89%, which meant it was off the charger for about an hour. I then swapped in a battery that had been sitting in a charger for a few days. It has been an hour and 45 minutes, with 10 minutes of awake time, and the battery is at 97%.

I believe, no matter how you do it, via USB or wall charger, charging a battery inside the EVO does not properly charge it. I get much better battery life than I ever got with my Touch Pro 2, now that I charge the batteries in external chargers.