What are the symptoms of a damaged car battery?

[StXavier]

Here are the signs before the battery is damaged: 1. The vehicle is more difficult to start than usual, requiring more than one ignition attempt, indicating insufficient starting power. 2. When the vehicle is idling, the headlights quickly dim from bright, indicating that the battery power is insufficient and needs replacement. 3. When the battery is nearing the end of its life, it will affect the operation of the alternator. Usually, abnormal noises from the alternator occur when starting the vehicle, typically a slight squeaking sound, which may disappear in two or three seconds or even shorter. As the power decreases, the frequency and duration of this noise will gradually increase. 4. The vehicle usually runs normally, but occasionally, after parking and restarting, it is found that there is no power at all. This is because when the battery is nearing the end of its life, the starting current is insufficient, causing an increase in oxide on the battery terminals, leading to a complete loss of power.