I regularly lurk over at XDA since I started -happily- using my HTC HD2 Leo (actually, I just brought it to a collection center for warranty servicing… dead touchscreen, sigh). Since then, I began reading about “funny” practices regarding lithium ion battery usage to prolong their life. Even before that, when I still used older pocketpc’s (namely, iPaq’s) I would always run down the battery to about 30% and then recharge to full, and I avoided at most to recharge before it was “time”; on the other hand, you can often read guides saying that LiIon batteries get better the more often you recharge them, and get worse the bigger and less frequent the charges (sure, now tell me your laptop battery improves by always using it attached to the mains charger…).

Following is an excerpt taken from here (I suppose these are pretty standard steps, I’ve read similar ones on some XDA threads):

1. Run the device down until it turns itself off.
2. Turn it back on and wait for it to turn itself off again.
3. Remove the battery for 10 seconds.
4. Replace the battery, but leave the device off.
5. Charge the device until full and then for another hour.
6. **Root users only** Using a Terminal Emulator, type “su” enter, followed by “rm /data/system/batterystats.bin”
7. Run the device’s battery down until it turns itself off.
8. Turn the device on and charge for at least 8 hours.
9. Unplug the device, turn off, then charge for another hour.
10. Unplug the device, turn on, wait 2 minutes.
11. Turn off again and charge for another hour.
12. Restart and use as normal.

Now, the least of my intentions is to criticize their work in any way (believe me), yet, personally (very personally) I think you could insert in any place in that list the following statement:

• Dress in a striped white and greenish scottish skirt, and, while wearing ONLY that, during a full moon, jump yelling “IIIOOOONNNN” around your charging phone

and it would perfectly fit in the overall mood of said list.

On a side note, when the charging device says it’s full, it stops sending energy to the battery, so for any kind of purpose you could leave the charger attached for a whole day after the led got green, it won’t really make any difference.

I am an extreme case, and I know it, but I can very honestly report my experience: I have the standard original battery, and I bought off chinese eBay other 3 clones (1230mAh, perfectly identical to the original except a slightly tinier barcode), together with a desktop charger.

I use the phone until it runs down to ~20% (lately down to 10% or even 5% if I’m doing something I don’t want to interrupt, like reading manga) at which point I take out the battery, and put inside the next charged one (I have them numbered, from 1 to 4). The drained battery goes straight inside the desktop charger (or in my pocket, until I get back home).

I rarely use the car charger, but I kind of regularly use the phone inside the car as MP3 player/navigator.

I have gotten, on very light use, up to 4 days uptime. Yes, you read it well, FOUR days uptime; I may have used it very little, yet it’s still 96 hours. Are you going to tell me that with those tricks you read about it could’ve lasted even longer?