Lets first clarify on the maximum battery life.
Every lithium ion battery users should know that average battery life of lithium - ion based battery is about 2-3 years, however may vary depending of the temperature, battery cycle and shelf life.
The life of the battery last for about 300 to 500 cycles under room temperature, lower the temperature higher battery life.
Frequently charge the battery
Lithium and lead-based batteries do not require a periodic full discharge. In fact, it is better not to discharge them too deeply but charge them more often. Using a larger battery is one way to reduce the stress on a battery. charge the battery when it reaches 40%-60%, this wont harm the battery as there is no memory concern with lithium ion batteries, as i understand when the battery is below 30 % and after which it is fully charged, its considered as 1 cycle.
However it is recommended to fully discharge the battery once every 30 days, this ensure the calibration of fuel gauge.
Never over charge the battery
The lithium ion battery once fully charged should be disconnected from the charger, over charging the battery will lead to rise in temperature of the battery. there is also safety hazard if overcharged.
Never over discharge the battery
Battery should be recharged when it reach 30%, over discharging the battery puts pressure on the battery and affect the battery life.
These information has been picked up from here
