An aerosol generating device comprising: a heater configured to generate aerosol by heating an aerosol generating substance; a battery configured to supply power to the heater ; and a controller configured to estimate a remaining life of the battery characterized in that the estimation is based on at least two from among a first output voltage of the battery measured at a first time point, a second output voltage of the battery measured at a second time point that is later than the first time point, and a number of usage times of the aerosol generating device between the first time point and the second time point; that the controller is further configured to: calculate a first voltage drop of the battery by subtracting the second output voltage from the first output voltage; and estimate the remaining life of the battery based on the first voltage drop and a first estimated voltage drop corresponding to the number of usage times; that the first estimated voltage drop is determined in advance based on the first output voltage and the number of usage times of the aerosol generating device , and that the first estimated voltage drop comprises a first maximum efficiency estimated voltage drop, which is an estimated voltage drop when the battery is at its peak performance, and a first minimum efficiency estimated voltage drop, which is an estimated voltage drop when the battery is at its lowest performance. a heater configured to generate aerosol by heating an aerosol generating substance; a battery configured to supply power to the heater ; and a controller configured to estimate a remaining life of the battery characterized in that the estimation is based on at least two from among a first output voltage of the battery measured at a first time point, a second output voltage of the battery measured at a second time point that is later than the first time point, and a number of usage times of the aerosol generating device between the first time point and the second time point; that the controller is further configured to: calculate a first voltage drop of the battery by subtracting the second output voltage from the first output voltage; and estimate the remaining life of the battery based on the first voltage drop and a first estimated voltage drop corresponding to the number of usage times; that the first estimated voltage drop is determined in advance based on the first output voltage and the number of usage times of the aerosol generating device , and that the first estimated voltage drop comprises a first maximum efficiency estimated voltage drop, which is an estimated voltage drop when the battery is at its peak performance, and a first minimum efficiency estimated voltage drop, which is an estimated voltage drop when the battery is at its lowest performance. calculate a first voltage drop of the battery by subtracting the second output voltage from the first output voltage; and estimate the remaining life of the battery based on the first voltage drop and a first estimated voltage drop corresponding to the number of usage times; that the first estimated voltage drop is determined in advance based on the first output voltage and the number of usage times of the aerosol generating device , and that the first estimated voltage drop comprises a first maximum efficiency estimated voltage drop, which is an estimated voltage drop when the battery is at its peak performance, and a first minimum efficiency estimated voltage drop, which is an estimated voltage drop when the battery is at its lowest performance. <EOS>