While I am not personally familiar with LG phones, I know that a battery's talk time and standby time depend on its mAh number. Standard batteries generally have 900 mAh - this number should give you around 3 hours of talk time and 45 hours of standby time. Also, Li-ion batteries (after an initial charge of 8-12 hours) prefer frequent partial discharges (letting the bars get half-way down and then charging) versus letting the battery run all the way down and then charging fully back up.