What Degrades the Life of a Forklift Battery?

Learn what 8 things can dramatically shorten the life of your forklift battery.

Battery life expectancy is determined by usage, duty cycle, maintenance, recharging, watering, etc. Every application is different and to help increase your batteries life expectancy a proper planned maintenance program is a key factor. Here are areas of concern for a battery along with some suggestions to help increase the productivity of your battery.


Batteries should not be discharged below the 80% discharged level, except in emergency situations. Continually discharging to 100% discharge level will reduce battery life. Low voltage and high amperage also effects truck components (contact, brushes and motors).


Corrosion is an indicator of improper watering of batteries. If electrolyte is forced out of the cell it will corrode and weaken the steel tray, as well as causing other external component deterioration. When water is added, the electrolyte becomes diluted and thus loss of capacity. Methods to correct this problem include employing proper watering procedures (filling after charge, not before) and utilize an automatic cell filler or watering system.

Cut Cables

Cut cables are hazardous because of the possibility of electrical arcing. The burning action of the shorted cables can cause great personal and property injury. Hydrogen gas is a by-product during the charge cycle and is extremely explosive. Preventative measures include installation of plastic cable wrap. New cables should be replaced by qualified personnel because molten lead and flames are used.

Broken or Damaged Connectors

Cracked or broken connectors allow the contact tips to be exposed. This can lead to electrical shorting and possible battery explosion and should be repaired or replaced as soon as possible.


Sulfation is a condition in batteries where sulfuring acid crystallizes on plates and causes a resistance, thus preventing full charge back. If allowed to continue the battery will not accept a charge. Monitoring charging procedure and utilizing the equalize can help prevent sulfation.

Tray Damage

Corroded or damaged trays can drastically weaken the strength of the steel. Personnel injury and expensive repairs may occur. This can also lead to lift truck compartment and component problems.

Inconsistent Voltages and Specific Gravities

When we see voltages and specific gravities (acid concentration) vary we can expect problems in the near future. Further testing may be required.

Dry Cells

If electrolyte levels are low enough a portion of the plates will be exposed to air. This allows for sulfation and reduced capacity. Water should be approximately ¾ of an inch higher than the splash guard. Though if cells were exposed to air there may be damage to the cell and testing should be considered. (Only fill water after charge, not before).

A robust Planned Maintenance Program can combat these factors and increase the useful life of your forklift batteries. Learn more about our Planned Maintenance Program for your batteries.