Lead acid batteries are one of the most neglected pieces of equipment in material handling. Low water levels, corrosion, and electrolyte spillage are common issues that need to be monitored on a daily basis, but one practice that tends to be forgotten is the equalization charge. So, what is an equalization charge? I’m glad you asked!
What is an equalized charge on a forklift battery?
An equalization charge occurs when the battery is purposely overcharged after a full charging cycle. Essentially, you are charging the battery at a higher voltage than it is typically charged to help remove built-up sulfate and balance the voltage of each cell.
Why perform an equalized charge on a forklift battery?
If you don’t equalize your lead acid batteries, this sulfate is going to build up over time until it decreases the battery’s capacity. This buildup will effectively reduce your maximum run time, leading to more battery swaps or more time spent opportunity charging throughout the work shift. The voltage imbalance has a similar effect. Batteries work by using multiple cells that are connected in series to provide a certain voltage output. When you have varying power outputs in each cell, your overall battery voltage is reduced and your battery becomes discharged more quickly.
When should I perform an equalized charge on a forklift battery?
Equalization charges should be performed as suggested by the battery manufacturer, but many companies equalize their batteries over the weekend due to the long charging cycle. A full charge cycle is around eight hours for a standard lead acid battery and the equalization charge can be around an additional three hours. Equalization intervals will vary depending on your specific application, type and size of battery, and average operating hours.
How do I perform an equalized charge on a forklift battery?
First, you need a charger capable of equalization, as not all battery chargers have the same capabilities. Ensure you have the proper charging equipment for all of your forklifts. Some battery chargers will automatically equalize the batteries. This capability is more common in more sophisticated systems on smaller products such as electric walkie pallet jacks. Toyota’s 8HBW23 model, for example, automatically equalizes each battery cell during normal charging.
For batteries that do require manual equalization, be sure to follow all instructions provided by both the battery and the charger manufacturer to ensure you are following the appropriate steps for proper equalization. Equalization charges typically require longer cooldowns than normal charges due to the higher amount of voltage. Allow enough time for cooldown prior to using a battery that has been recently charged.