| 摘要 |
A vehicle-mounted emergency report device (2) having a function of transmitting an emergency report signal to a center device via a communication network when a vehicle is determined to have collided is provided with a backup battery (19) which supplies operating power when power supplied from a vehicle battery (17) has reduced, and a voltage detection unit (21) which detects the voltage of the backup battery (19). The vehicle-mounted emergency report device is further provided with a first determination unit which determines whether or not the detected voltage is lower than a threshold for warning of battery exhaustion, a second determination unit which determines whether or not a secondary differential coefficient obtained by secondarily differentiating a battery voltage function with respect to time is negative, and a warning unit which does not warn of battery exhaustion when the detected voltage is lower than the threshold for warning of battery exhaustion and the secondary differential coefficient is not negative, and warns of battery exhaustion when the secondary differential coefficient is negative. Consequently, a decrease in the discharge performance of the backup battery can be accurately detected. |
