Calibrating HTC Desire Battery
If you’ve got HTC Desire and disappointed with its poor battery life
and you’re turning off WiFi, GPS etc in order to conserve battery, maybe it just needs to be calibrated?
1. Connect phone to the charger with the phone powered on and let the phone to charge until the notification LED is green.
2. Disconnect the phone from the charger, and power it off.
3. Reconnect the phone to the charger with the phone powered off, and allow the phone to charge until the notification LED is green.
4. Disconnect the phone from the charger and power it on. Once the phone is powered completely on, power it off again and reconnect it to the charger until the notification LED is green.
5. Disconnect the phone, power it on, and use it.
You need to use this sequence only once. If the issue of battery life on our phone persists, I recommend you contact our HTC accessory department directly.
[via XDA]
[Update: info added by INSPOADAM]
For those that want to know what is happening here. When you plug in the charger and the phone is on, the battery will charge up to the point where the phones operating system THINKS is 100%. If this is say 90%, you will effectively not be using 10% of your battery. When you turn your phone off and plug in the charger, the phones operating system is not active so the battery will squeeze in as much charge as it can. In this off state, the LED function is controlled by how much current the charge process is drawing – i.e. when the current drops below a certain amount, the LED changes from orange (charging) to green charged. When you turn you phone back on, the OS know that the sequence of events carries out above is effectively telling the phone that the battery is at 100% and it should recalibrate to reflect this. Everything else from then on is just scaling of the 100% battery life – i.e. when we were only using 90% of the battery, 50% on the phone is actually 45% of the total battery capacity but now we are using 100%, 50% is actually 50%. This is one of the reasons that the phone will suddenly go from say 15% to dead – as the battery drains, the discrepancy between actual battery life and the battery life the phone “thinks” it has becomes more significant.
FYI, If your phone is off and when you plug the charger in the LED goes immediately green your battery if fully charged. If you are getting really bad battery life after that (i.e. even worse than normal), you battery may need replacing.
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Faizan on August 18th, 2010 at 10:18 AM
@Adeel, Compare this to iPhone 4 not 3g :p