The Economic Times has an interesting article on how to increase your cell phone battery life. Here’s a summary:

  1. Don’t drop your cell phone and handle it with care. In order to pack the maximum charge capacity within the least amount of weight and volume, the structure of batteries have become quite complex. Dropping or handling your cell phone roughly could damage your battery.
  2. Beware of the heat and avoid direct sunlight. Batteries are designed to work within certain temperature range. Overheating the batteries will most certainly cause permanent damage. Don’t leave your cell phone on the dashboard of your car, and don’t store it under direct sunlight.
  3. Don’t leave your battery on the charger. Although most phones have overcharge protection, it is useless to leave your phone on the charger for more than the specified time. The battery can’t hold more charge than it is designed for. Furthermore, most batteries have a fixed life span of 400-600 cycles of charging. Once your cell phone is done charging, the battery discharges through the device. The charging could start again if the battery drops too low. However, most recent phones will draw power directly from the charger when they are connected, so this tip might not be applicable for every cell phone.
  4. Don’t completely discharge the battery before recharging. Unless you’re still using batteries with a memory effect (ie. nickel-cadium batteries), it is better the recharge the phone once the battery is at 5-10% of the total charge. Lithium-ion batteries work better that way.

These tips will work for most cell phones, but it is always a good idea to follow your user’s manual guidelines concerning charging and cellular phone handling.