NEW BATTERIES: Give your new battery a full uninterrupted charge before use. If the battery does not start charging within 15 mins, remove it and clean the gold terminals on the battery and the phone, using a clean dry cloth. Replace the battery and leave for another 15 mins. If still no charge then try and turn the phone on during charging.
It is healthy for a battery to be run flat periodically. Always try to not interrupt the charging cycle.
The capacity of a New Battery will increase over about 5 full charges.

OLDER BATTERIES: Ni-Cad and Ni-MH batteries have a memory effect, this means that they remember at which point of discharge they were re-charged. So if you continually recharge you battery at 50% empty, then eventually it will only last half as long. Always discharge these types of batteries completly before re-charging. This will extend the overall life of the battery quite considerably.

Li-Ion batteries do not suffer from this, but it would not hurt them to fully discharge now and again.

We can supply any battery, a small selection is in Our Ebay Store