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3rd March 2011, 01:39 PM |#10  
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Calibrating Without Downtime!
Edit: If this doesn't work on your device, try the Die-Hard Battery Calibrator Script to ensure a proper charge

This is proven to work with Motorola Milestone so I would imagine the Droid as well.
It works with the Milestone 2 but you may need to get the phone booted up manually (step 7) instead of the easy reboot in step 6.
If you have a different phone and this works, please let us know!

You probably won't believe that this will work but try it anyway.

The big benefit of doing it this way:
It's great if you don't plan on changing roms and just want to calibrate your battery without downtime so that you can just use your phone as you normally would.

Note: Be sure that the phone isn't running hot (feel the back)

1. While in Android, charge up to 100% and leave the phone plugged in.
2. Delete /data/system/batterystats.bin
3. Remove back cover
4. Press Power and choose to reboot normally.
5. When the screen goes black and the lights go out, pull out the battery before you get the M logo. It will probably still work after the M logo shows up but that's how I do it.

6. Surprise: The phone will boot up without the battery! - Mine does - every time

Note: Batterystats.bin is recreated when you see the M logo - even though the battery isn't in the phone.

Go to Step 8 if the phone booted up as described.

7. If it doesn't boot up and you see the battery with the ?
..........a) Put the battery back in (you will see 60%),
..........b) Power off the phone (press power until LED light goes out)
..........c) Power on the phone (press power until you see the M logo)
..........d) Remove battery... and watch bootanimation...

8. a) After the surprise of seeing the boot animation without a battery, you will then see the lock screen along with a "No SIM card error" and no signal.
...... Put the battery back in - the SIM card error will disappear, you will get a signal, it will show 60% full and the icon will show the battery charging.
...... Go to Step 9 if this works as planned. If it doesn't, reboot (again without the battery) and use step 8b instead of step 8a.
... b) Put the battery back in during the bootanimation, but after the haptic feedback/vibration (and the buttons along the bottom light up).
....... On a normal reboot, you can actually slide and unlock the phone when you get the vibration during the boot animation. You knew that, right?

9. Use your phone normally while you calibrate the battery

10. Let it fill it up to 100% + 15 minutes or so. When it is truly finished charging, the battery should be cool.

11. If the phone is running hot, weird things can happen. For example, you may get no signal when you put the battery back in or the battery doesn't begin charging (the status bar battery icon doesn't change). Just let the phone cool off and it should work next time.

100% full is approximately 4200mV
As you can see in the cap below, it's showing only 60% at 4241mV (This was after booting up without the battery and putting the battery in)
A few minutes later, still plugged in, it showed 100% at 4225mV and then it went up to 4230mV.

Finally, I then unplugged the phone and I got a reading of 4196mV

Now, when I charge it up, it will go up to 4230mV everytime. I leave it plugged in an extra few minutes after that.
I highly recommend Battery Monitor Widget
Batterystats.bin gets recreated if you unplug your phone and plug it in again. So don't do that. Let it get recreated on the M logo (Step 6).
Thanks to pcphobic for a couple of important tips and to pcphobic and sileshn both for confirming that my phone isn't possessed!
Last edited by zeppelinrox; 24th April 2013 at 05:04 AM.
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