Toshiba says it does and that is why my Portege battery loses charge when in the computer is not used for a few days but stays fully charged when I remove the batter for the same length of time. For instance, the battery was completely dead (computer wouldn’t turn on) when not used for 9 days but after 3 1/2 days with the battery out of the computer, it showed 99% after booting. Both times the battery had a full charge at the beginning.