Does a full drain help prolong the Li-ion batteries life?
Li-ion batteries do not exhibit the “memory effect”. The lifetime delivered by li-ion batteries is a function of the number of coulombs delivered- provided that it is used within the specified temperature ranges, etc. There are some cautions with this issue, however – coulomb counting gas gauges can require a learn cycles to accommodate for the reduced capacity over the life of the battery, and Li-ion batteries do not like to be held at a high state of charge for a long period of time.