text: can i charge lion batteries discontinuously? i use lion batteries on my phone and laptop..i would like to know if the lifetime of these batteries decreases if u charge sporadically? do we always have to charge when the power goes completely down? the battery itself degrades over time, which is probably the most significant cause of the lifetime degeneration.  you can build up memory cells by charging at half-full very time, but those go away once you complete full charge/discharge cycles.