Low electrolyte level
The electrolyte level in an open battery (not maintenance-free battery and AGM-batteries) must be checked regularly. The water in the electrolyte is consumed by gas production and absorption. Batteries have different water consumption. This depends on design and ambient temperature. The water is used more quickly in hot climates.
If the electrolyte level is too low, the battery may suffer corrosion and the capacity of the battery may be reduced. Corrosion may occur in the connections between the cells. The consequence may be an open-circuit in a connection which will prevent the battery from supplying a current.
The capacity of the battery is reduced if the electrolyte level is so low that some of the surface of the plates are not submerged in electrolyte. Such surfaces cannot contribute to the chemical processes that occur during charging and discharging.
Note Check the electrolyte level regularly and top up with distilled or deionized water to the indicated maximum marking. Never use tap water