Start to operate immediately after the purchase: lithium-ion batteries sold partially charged.
Most try to charge the battery. On average, the device is designed for 350-450 charging cycles. However, the service life will increase if you connect a battery to a power source before the battery is fully "sit". Pay special attention to the fact that frequent discharging to zero is not recommended.
Every few months, allow the battery to discharge fully. It is necessary for the proper functioning of the IC, monitoring the status of the device.
In the event that the battery is powered from a network that does not have time to fully recharge and you need for any reason to turn it off, do it without fear to damage the battery. Leaving the device connected to a power source once it's fully charged, and will not adversely affect his work.
Do not purchase the battery in store. The unused capacity of the battery during the storage can be reduced.
If there is a need to "conserve" the battery for a while, store it partially charged. A discharged battery after prolonged storage may not be included. At the time of "idle" battery put in the fridge, so it is better to retain their properties. This is because the battery is spent more intensively at high ambient temperatures than at low, even when the power is off the device.
Never charge the battery when the air temperature is below zero. After several such cycles the charging device is likely to be worthless. Also beware of overheating of the battery, keep it in close proximity to heat sources. The optimum temperature for the lithium-ion battery is 19-35 degrees Celsius.
Don't skimp by purchasing the battery. Chinese products loses much in quality batteries of known manufacturers. Besides a high probability that a cheap battery will explode, hopelessly ruining your phone.
"Lifespan" of the battery is 2-3 years. Do not attempt to "resurrect" the device after its life came to an end, it's useless.