I think there is a worldwide consensus that the EVO could use more battery power.

I will be looking to get the 3500 mAh battery from Seidio once Seidio releases their Rugged case to fit the extended battery door.

 

My battery life was fine for months -- charge easily made it through a 12 hour day unless I pounded email/web -- but suddenly in last three weeks it has plummeted sharply (sometimes less than 6 hours). I notice the following other symptoms: (1) Phone suddenly gets very warm (never did that before); (2) At least once a day, it randomly reboots itself; (3) It periodically slows down drastically -- data entry when I type sometimes doesn't take at all, or takes a while to work; (4) The home page weather and time widget fails to update; (5) Certain other things stop displaying properly. This is after it has always worked flawlessly. BTW, I use no Twitter, Facebook, etc. I'm almost entirely an email (Microsoft Exchange), phone, calendar, and occasionally web user, with some GPS use, OpenTable, rarely use Pandora, etc.

Anyone know what would cause this sudden change for the worse in battery life and overall performance?

 

Rooted phone with installed 3500mAh battery.
Makes ALOT of difference in battery life. Highly recommend!

Attched are two battery life screenshots.
One at about 9 hours unplugged and another at about 27 hours unplugged.

 

I am having the same problem and it started about three weeks ago. I've had the EVO since the second week of its release and it has worked great. My battery has always lasted the entire day. They changed something.

 

Same problem here, although I think mine started before the first post in this thread. The only thing I have found to prolong battery life is to leave it on vibrate only. I know its weird, but if I have the volume set to vibrate, I can get a whole day/night out of the battery. Whereas before, it wouldn't last thru the night.

 

I thought it was just me. I have had awful battery life for the past couple of months. I thought it was due to apps or the fact that mine constantly runs low (which is not good for li-ion) but using spare parts I cannot find a single app that's causing high awake time. In fact my awake times are still around 15%. So I have no idea what it is but I have been upset lately by the crappy battery life.