Charging time is generally presented as charging to 100%, however in terms of prolonging the life of a Lithium Ion battery this is the worst thing you can do. The ideal for battery life would be using 10% then charging to the previous figure, however in practice . As a rule it’s best not to charge above 80%. Slower charging is better than fast and Rapid chargers should be used as little as possible.
Leaving a battery at either 0% and 100% charge levels are very bad for it, as is allowing the battery to get hot. Hence the need for a Battery management system.
Tips for extending the lifetime of Lithium-ion batteries – Michigan University
How to Prolong the LIfe of Lithium-based Batteries – Battery University
Battery Ageing in an Electric Vehicle – Battery University