Late To Party...
I'm a little late to the party, but here's my experience with Lithium Ion batteries.
I've had my current phone (MotoRizr Z6TV) for 2.5 years now. My battery lasts on stand-by with occasional use (about 10 texts sent/received per day, 20 min of talk time per day, pics taken/sent daily) for at least 7 days (well over the reported time). A couple friends have the phone, and none have reported even close to results like I've gotten (one friend said she might get 5 days, max with less use than I put mine through). I've been getting the same life out of it for all 2.5 years. I always get good reception, but not great, in places I frequently have the phone.
When I first got the phone, I conditioned it by running it dead out of the box and recharging it full, doing that for the first few charges. After that, I only recharged the phone when the low battery indicator came up (which I believe is 10% life or less), occasionally letting it die completely. And, I never charged the phone while it was powered on. I also rarely let it sit on the charger for long after it was fully charged. And, as I've said, my battery life doesn't seem to have gotten any worse over the years. If it has, its been such an incremental drop I haven't even noticed.
I read posts from people saying that all of the steps I took with my battery actually mean very little in terms of battery life, and some steps I took (letting battery die/get so low before charging) even have negative impacts on the battery life. But my experience seems to support the contrary.
I am no expert in the field of batteries, so if someone who is says otherwise I believe them, as my experience may be the exception. And I am not against the notion of charging cycles having a lot to do with it, considering I've only put my phone through maybe 130 cycles over its life.
However, regarding my routine, I have one question that I have yet to see be answered in terms of Lithium Ion batteries. I was told that utilizing a battery while it is charging is not a good idea. One reason being that this forces the battery to get extra hot, as it is pulling double duty (accepting a charge and powering the device), which we know is not good for overall battery life. This is also my laptop manufacturers don't recommend charging a laptop while using it. Is this a sound theory?
Thanks.