1. If the car has not been used for more than two months, the battery must be removed and charged. The optimum battery storage temperature is between 0 and +27°C. At these temperatures, battery self-discharge is minimal. The battery must be charged at least once every two months, otherwise it becomes unusable.
Battery that has not been used for a long time (e.g. the vehicle has not been used), is discharged and, in addition, can be sulfated. If such a battery is charged by a fast charger, it will not accept the charging current or become too fast due to sulfation "fully" charged. Actually the battery is damaged.
Before identifying a battery as damaged, check the following:
2. Electrolyte density. If the difference between the densities in individual sections does not exceed 0.04 g/ml, then it is necessary to charge the battery with a normal charger.
3. After charging, test the battery under load. If the battery performance is below the Specifications, the battery is damaged.
4. If the density of the electrolyte in one or two adjacent sections is noticeably different (for example, in five sections 1.16 g / ml, and in the sixth 1.08 g / ml) The battery has a short circuit and needs to be replaced.