Avoid 100% Discharges To Extend Your Battery Life

Life Hacker has it almost right. The link to the Battery University shows that smaller depth of discharge leads to being able to have more discharge cycles. However the small discharge before recharging means lower time on battery and more frequent charging.

If we assume close to linear discharge to time used, and make the sum of all the time the battery is used with a full discharge cycle as 1 power time.

A half discharge cycle gives you 1.5 times the total power time of the full discharge.

A quarter discharge cycle gives you 1.25 time the total power time.

A tenth discharge cycle gives you 0.94 times the total power time.

So maximum battery life is best obtained by charging at 50%.