Charging the Thunderbolt using a non-oem charger getting better battery life

Hello all, I am looking for input or advice, I have had my Thunderbolt for a few months now and must say I love it, except for the battery life.  I live in a 3g area and after about 3 hours with a 4 minute call I am down to 80% charge.  My question is, I purchased the ebay batteries and charger deal, 2 1800mah batteries and the battery charger which has a usb port for charging the phone. One day I decided to start using the USB port on this charger to start charging my phone with the OEM battery in it and I am experiencing EXCELLENT battery life..The phone is actually a joy to have with the better battery life! I have no idea why this charger is charging the battery so much better but the problem/question is when my phone is charging on this charger the screens seem to lag and responsiveness decrease's, this is not a big deal since I do not really use my phone while charging and all is normal when I unplug the phone. I am just nervous because the stock charger is 5v 1a, and the non oem charger says usb output 5.2v, 800mah.  I have read online that it is ok to vary the voltage for usb devices  by .1 or .2 up or down, but I am just looking for your input. Would I be safer charging the phone with the phone off? Should I discontinue use altogether?  It is just hard to discontinue its use because I swear by the fact that the battery life with this charger has improved by so much.  If this charger will just possible mess up the battery I am fine with that since they are avail. on amazon for 10 dollars, I just dont want to do damage to the phone.. Any input would be greatly appreciated!!

                                                                                        RescueEMT911

 Thanks so much for the response! I was just concerned that using the non-oem charger which puts out 5.2 volts might damage my phone since the htc oem charger is 5volts, but I talked to my cousin tonight who is an electrical engineer designing supercomputers for military use and he said that the .2 difference in voltage will not harm the phone at all, he said even with the most delicate of chips there is no  concern unless you start going over .5+ in voltage.  I don't have an explanation as to why this charger seems to charge the battery deeper of have it last longer, but I do know that under pretty much the same type of usage the stock charger will have my phone last from like 10am-5pm, and with that charger, I can take the phone off at 10am and it still has a good amount of battery left at 11pm.. so I guess I will continue to use the non-oem charger since it seems to be working for me, and feel more safe knowing that the voltage difference is not going to do harm to the phone itself..

                             RescueEMT911

I may have to try using the non oem charger to see if I see a difference. I'd love a better battery life!

A slower charge will always give you a deeper charge.  When charging a battery there is normally a thermal protection circuit that shuts off the charging when a set temp is reached to protect the phone and battery.  The faster the charge the faster the heat build-up.  So charging will stop before the battery is really full.

As for the amps the charger can put out.  Use can always use a charger with a higher amp rating, within reason.  Current is pulled not pushed.  A higher amp rating allows a device to draw more current up to its limit.  That's why you can plug a 1 or 2 amp radio into your 15amp wall circuit at home.  On the under current side, there is a lower limit at which the device will no longer function.  There's not a set formula, it is based on the device's design.

Holefully this helps explains what your experiencing.

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