Battery self-heating system and vehicle

A battery self-heating system includes: a power battery pack, a first heating device, a second heating device and a controller. The power battery pack includes a first battery group and a second battery group connected in series; the first heating device includes a first heating sub-device and a second heating sub-device; the second heating device includes a third heating sub-device and a fourth heating sub-device; and the controller is configured to: control the first heating device and the first battery group to be alternately charged and discharged, control the second heating device and the second battery group to be alternately charged and discharged, and control, when a first one of the first battery group and the second battery group is in a discharged state, a second one of the first battery group and the second battery group to be in a charged state.