Low voltage warning method and device for vehicle secondary battery and vehicle provided with such device

A low voltage warning method for a vehicle secondary battery and a device for same are provided. The method includes a voltage detecting step of starting detecting the voltage of a secondary battery after a specific period of time, required for the voltage of the secondary battery to become substantially stable since a vehicle stops charging the secondary battery; a storing step of storing a detected voltage as a sample voltage Vs after the voltage of the secondary battery is detected; a comparing and judging step of comparing the sample voltage Vs with a predetermined threshold voltage Vth and judging whether the sample voltage Vs is less than or equal to the predetermined threshold voltage Vth; and an output step of outputting a warning when it is judged in the comparing and judging step that the sample voltage Vs is less than or equal to the predetermined threshold voltage Vth.