How to Determine if a Car Battery is Good or Bad?

[DaniellaRose]

Methods to determine the condition of a car battery are as follows: 1. Checking the electrolyte level in the car battery: The electrolyte level can be measured using a glass tube. Normally, the electrolyte level should be 10~15mm above the plates. For new batteries, the electrolyte level can be observed through the height indicator line on the side. If the electrolyte is insufficient and it is confirmed that the level has decreased due to electrolyte splashing, distilled water should be added. 2. Checking the discharge level through electrolyte density: The discharge level can be roughly estimated by measuring the electrolyte density. Generally, for every decrease of 0.01g/cm2 in electrolyte density, it is equivalent to a 6% discharge of the battery. Note: The measured electrolyte density needs to be converted to a value at 25°C before making a judgment.