Sulfation is a chemical process that causes a build-up of lead sulphate crystals on the cells of a battery. This process naturally occurs to some degree in normal lead-acid batteries, but a large amount of sulfation can cause longer charging times, depleted cranking power and shorter overall battery life. Small amounts of sulfation will break down when a battery charges, but comprehensive sulfation will not, requiring the battery to be replaced.

Improper charging (prolonged low charge or not fully charging the battery) or a lack of water in the battery’s catalyst solution can cause sulfation. Sulfation can be diagnosed visually (a grey or grimy appearance is typical) or more precisely with a multimeter.

SHORTENED RUNNING TIME

Forklift batteries should, on average, last for 1500 charging cycles. If a battery’s charge quickly runs down long before the expected end of its life, there’s a good chance the battery needs to be replaced.

A battery that fails to hold its charge can be caused by overly-frequent charging such as ‘topping up’ a battery’s charge before it needs it.

DIM DISPLAYS AND LOWERED POWER OUTPUT

An overall lack of power in a forklift (often seen in dull displays) is another sign that a battery may need replacing. Causes like sulfation will generally indicate that replacement is necessary, though poor terminal connections and other contaminants may be fixed or cleaned without replacement.

CORRODED AREAS SURROUNDING THE BATTERY

If a battery is poorly maintained or otherwise subjected to stress, there is a risk of corrosion. Corrosion of battery terminals can reduce the effectiveness of charging and eventually lead to the battery needing to be replaced. Corroded terminals can be repaired by a battery manufacturer, though either replacement or repair can be prevented with a schedule of regular forklift battery maintenance.

SPILLED ACID/ DAMAGED BATTERY HOUSING

Acid leaking from a battery is never a good sign. The presence of battery acid can indicate severe battery damage and pose health and safety risks. If you notice acid collecting on the outside of the battery, it’s best to proceed with caution and use the correct PPE. Though repairs can be made to damaged batteries, they need to be carried out by professionals. In general, if you see acid on the housing, it’s a sign that the battery needs replacing.