Here’s a good recommendation about prolonging your battery life.
Depth of Discharge of the li-ion determines, how long will your battery last. Basically, it means how deep is the discharge level of the battery when you put it back on charge. For instance, I’ve started charging my battery yesterday overnight when I had 20% left. So the DoD in this case is 80%. Number of the Discharge Cycles means how many times can you charge your battery until it becomes unusable.
Here’s the comparison table of DOD against discharge cycle count: