In the same way, that different deep-cycle battery designs vary in capacity and overall performance, charging the battery can be as unique as the battery itself. Because deep-cycle batteries in various vehicles and machinery can differ in their work environment, the battery’s capacity and performance are susceptible to how they are charged and maintained. Battery manufacturers like U.S. Battery work with charger manufacturers such as Delta-Q to develop various charging profiles for particular battery sizes and designs to maximize your lift’s battery performance. Ultimately, the overall performance of any work platform comes down to how well the batteries are maintained, the depth of discharge, and the “charge quality” during each recharging session.
According to Delta-Q, the manufacturer has more than 50 charge algorithms on hand for a variety of batteries. To determine how to give your equipment’s battery the best charge, you need to understand what charge algorithms are. There are different charge algorithms available on many battery chargers, but to understand this, you first need to know that there are basically three stages of battery charging. The first is a Bulk Stage, where the charger uses constant current at full charger output to bring the battery to approximately 80% state of charge. The second stage is Absorption Charge using constant voltage where the charge current tapers from full charger output to a lower level that depends on battery conditions. The charger allows the battery to control the charge rate at which it can accept a charge until 100% of the amp-hours removed on the previous discharge are returned. At this point, the battery is not quite fully charged and requires a controlled overcharge. The third stage is the Finish Charge, where the charger gives the battery a lower constant current charge at a charge rate that is proportional to the design capacity of the battery. Assuring the battery is fully charged and provides enough gassing to mix the electrolyte to prevent electrolyte stratification.
During these three charge stages, charge algorithms can differ in current, voltage, time, and amount of overcharge. Charge algorithms are adapted to optimize charging for specific battery models and chemistries. To begin with, there are three primary types of algorithms. SPECIFIC charge algorithms that are custom designed in collaboration between the charger manufacturer and the battery manufacturer and are used by most Original Equipment Manufacturers (OEM) of access lifts and machinery. For performance and warranty reasons, lift OEM’s use a specific battery and therefore require a particular charge algorithm to maximize the battery life for the performance and use environment of the equipment. Depending on the battery chemistry and its use, the charge time and current applied during these three stages can vary to provide the best possible balance between cycle life, runtime, and overall battery life.
Some charger manufacturers use GENERIC charge algorithms designed for particular battery chemistries (such as flooded lead-acid, AGM or Gel) and a wide range of amp-hour capacities. Each chemistry requires a different charge algorithm and amount of overcharge. According to charger manufacturer Delta-Q, a generic charge algorithm will provide a reasonable compromise between battery life and performance. Generic algorithms provide greater flexibility between battery makes and models, especially if the owner decides to change to a different battery when it’s time for the battery to be replaced.
Some charger manufacturers offer UNIVERSAL charge algorithms that can be used for all types of batteries, and most battery manufacturers do not recommend the use of these algorithms. If used, battery state of charge and temperature should be carefully monitored to prevent undercharge or overcharge that could severely decrease battery performance and life.
Ultimately, the best way to get the most out of your batteries, and your lift equipment, is to consult with the manufacturer and/or look up the charge algorithm they have for the specific battery in your equipment. The battery charger should use that specific charge algorithm; allowing you to get the most out of your batteries and ultimately your equipment. For more information on batteries and charging profiles, visit www.delta-q.com.