This battery will charge in about 5 hours to a slightly lesser autonomy with my laptop Dell Latitude 6430u and 16 GB of RAM for working developer. I have configured the bios for the microprocessor does not slow down because the battery connection of the external battery is not detected by the hardware as a charger! Good design, it thick but less weight compared to some similar product. Warning this external battery is not charging my internal battery when the computer is on or in standby. This battery provides power for the computer and a smartphone at the same time that he is also charging.