Battery life time depends on its capacity and in layman terms it called life cycles[LC], one LC = battery charge from 0-100. Meaning if you drain out a fully charged[100%] battery power completely then the battery is said that consumed a LC.
For most cell phone batteries, its ranged around 300–500 LCs. when it reaches that limit, battery duration starts slowing down.
According to Battery University, most Li-ions charge to 4.20V/cell, and every reduction in peak charge voltage of 0.10V/cell is said to double the cycle life. For example, a lithium-ion cell charged to 4.20V/cell typically delivers 300–500 cycles. If charged to only 4.10V/cell, the life can be prolonged to 600–1,000 cycles; 4.0V/cell should deliver 1,200–2,000 and 3.90V/cell should provide 2,400–4,000 cycles.
Most chargers for mobile phones, laptops, tablets and digital cameras charge Li-ion to 4.20V/cell. This allows maximum capacity, because the consumer wants nothing less than optimal runtime.
Ways to improve Life Span of Your Phone Battery
Calibrate a New Battery Properly
When you buy a new phone or battery, drain the new battery to below 5% [probably 1-5%] and then keep it for full charge[100%] for the first time, this way you will kind of calibrate the new battery’s power and configure it’s capacity.
Do not Use Phone When Charging
A device should be either be turned off or left alone while charging. This allows the battery to reach the threshold voltage unhindered and reach a low saturation current when full. A parasitic load confuses the charger.
Charge Your Battery Appropriately
Current battery technology does not have memory effect. However, you should not wait till the battery is almost exhausted to recharge it. So battery experts recommend you recharge when the battery is down to 30%-60%, however, the main point is not to let your battery drain out completely (get below 10%) before recharging. This increases the battery life, if you follow the advice regularly. Also once a month discharge the battery almost completely (down to about 10%) before recharging it. This helps battery indicator to precisely display the charge left (calibration of indicator).
General Advice for better Battery Efficiency
– Dimmer screen brightness if not required.
– Close/ kill unused processes.
– Don’t use the device in low battery conditions.
– Do not drain battery frequently below 30%.