Proper charging and maintenance of Sealed Lead Acid (SLA) batteries is crucial to ensure they have a long life. With a wide range of SLA battery chargers available today, it’s quite easy to find one that best suits your needs. Before we explain on how to charge SLA batteries, take note that the sulfuric acid in the batteries is highly corrosive. Hence, whenever you’re handling batteries, make sure you have protective gear on!
Charging One Battery
Connecting a single SLA battery to a single charger is quite basic, but you have to make sure that the charger is properly connected. The black connector of the charger is connected to the negative terminal of the battery and the red connector is connected to the positive terminal. In simple words, remember to connect positive with positive and vice versa.
Charging in Batteries Series
Charging Two Batteries in Series with Two Chargers
The key here is to connect two 12V SLA batteries in series to form a 24V battery pack. To make sure that both batteries are recharged completely, connect both of them to single battery chargers. By incorporating two chargers in the series, you can eliminate the problems that are commonly associated with cycling batteries.
Charging Two Batteries With One Charger in Series
By using an individual 24V battery charger, you can charge two 12V SLA batteries that represent a 24V battery pack.
Charging Batteries in Parallel
Charging Two SLA Batteries in Parallel
You can charge two 12V SLA batteries in parallel configuration through an individual 12V charger. Take note that the blue wire is used to distribute the drop in voltage across the batteries and all wires when charging. Though this is not critical in low current chargers, when you use 10 amp or higher range charges, the differential is voltage becomes significant. Connect the red wire to the top and the blue wire to the opposite end of battery pack.
Charging four SLA Batteries with Two Chargers in Parallel
The best method to charge four batteries that are connected in a parallel configuration is to use an individual 24V SLA charger rather than employing two 12V chargers. The black connector is connected to the negative end of the battery pack while the red connector is connected to the positive end. In a similar manner seen in the previous method, a blue wire will be used in balancing any drop in voltage evenly across all batteries and wires while charging.