Battery life optimization

Old Ni-Cd based batteries had the "Memory effect" in them which needed re-conditioning by deep discharge after every few days to increase the battery time-span. This misconception has carried on to the Li-ion batteries which are actually damaged by deep discharge. They are meant to be charged early and often so as to work well and have a better battery life.

Lithium ion batteries which are mostly used in the current laptops and cellphones, are better charged often than fully discharged and charged again each time. Totally discharging the battery will damage the cells. Shallower discharges are also said to have better effects according to some research.

This doesn't mean that you need to start searching for a power source as soon as possible, the notification that comes at 10-11% of your battery to plug in a power source is already calibrated so that you charge your battery from that point onward instead of completely depleting it. Same goes for your smart phone as it automatically turns off instead of completely depleting your Li-ion battery.

Conclusion: Discharging your battery up-til the last bar of your cell phone (or even till the low battery notification is fine but not above that... same goes for the laptop (in this case till the 7-11% notification).

Further information:

1. Storage: Lithium ion batteries oxidize the least at atleast 40% of charge left in them which is the best way to store them for longer periods. Long term storage of a fully charged battery is also damaging because of the leaks where as storing a depleted battery damages the cells.
2. Over charging: Overcharging should only be performed for calibration of the software and is other wise damaging to the battery.
3. Should I disconnect my laptop charger after it is fully charged?
   No, the laptop discontinues charging after the battery is fully charged and it is safe to keep it connected. Infact, this prevents unnecessary usage of battery and all together skips the charging / discharging fatigue of the battery by using the AC power instead (the cell phones don't use AC power like laptops even if connected to charger).