A mounting system according to one embodiment includes: a battery container having a charging terminal and configured to store a secondary battery; an electronic device having a power-supply terminal and configured to attach the battery container detachably; a mounting device having an external power-supply terminal to supply external power and configured to mount the battery container or the electronic device; and a joint mechanism configured to join the electronic device and the mounting device when the battery container is not attached to the electronic device. The joint mechanism does not join the electronic device and the mounting device when the battery container is attached to the electronic device.