Charging Instructions
U.S. Battery Charging Recommendations
U.S. Battery Manufacturing Company, Inc. recommends the use of ‘opportunity charging’ or charging batteries and battery packs at every opportunity while in storage or service. Following this recommendation will assure that batteries are always at the highest possible State of Charge (SOC) to maximize performance and range and to minimize the battery’s Depth of Discharge (DOD) to optimize performance and life.
U.S. Battery is active in the development of new charging methods and regularly tests and evaluates new charger technologies. As part of U.S. Battery’s charging recommendations, charging methods are categorized into three basic methodologies based on the number of charge stages used in the charging process. It should be noted that the basic charge stages should result in a fully charged battery at the end of the final charge stage. Using this criterion, float charging, maintenance charging, and equalization charging are not considered to be one of the basic charge stages. These basic charge stage methodologies can be defined as follows:
- Three-Stage Charging – Charging using bulk charge, absorption charge, and finish charge (usually constant current – constant voltage – constant current).
- Two-Stage Charging – Charging using bulk charge and absorption charge only (usually constant current – constant voltage).
- Single-Stage (Ferroresonant) Charging – Charging using a single-stage charge with tapering current and voltage.
U.S. Battery’s charging recommendations for deep-cycle flooded lead-acid (FLA), and sealed absorptive glass mat (AGM) batteries are attached. Note that the charging parameters recommended for each of these depend on both the battery type and charger type. These charging parameters are often controlled by specific charge algorithms that can be selected or programmed by the user. Users should consult the charger manufacturer and/or U.S. Battery for proper selection or programming of algorithm controlled chargers. U.S. Battery prefers the use of Three-Stage Charging with dV/dt charge termination to minimize the charge time required for full charge and to reduce the risk of abusive undercharging or overcharging of batteries and battery packs.
Recommended Charger Manufacturers*
*Note: Users should consult the charger manufacturer for proper charger selection, programming of algorithm-controlled chargers, and connection procedures for their specific application(s). This list of compatible chargers is intended ONLY to assist customers in search of charging solutions which, when tested under laboratory conditions, have met certain industry standards. U.S. Battery does not provide a warranty for any charger-related issues, including the charger, overcharge, undercharge, or incorrect wiring. Nor does U.S. Battery accept any liability in issues related to charger failure or malfunction.