A method for monitoring the remaining service life of a battery used for operating a field device in automation technology. The present power consumption of the battery is ascertained. Then, during a first phase of life, power consumption of the battery ascertained during operation of the field device is compared with a predetermined threshold value. In the case of exceeding the predetermined threshold value, during a second phase of life, the battery is exposed to defined load spikes at predetermined time intervals. Voltage collapses corresponding to the defined load spikes are detected, and a warning report is generated when the voltage collapses reach a predetermined maximum limit value.