In simplest terms, a charge algorithm (or charge profile) is a set of instructions the charger follows for optimal charging of the battery. Our algorithms are developed by working closely with the battery manufacturers to meet their charging recommendations for each model.
You'll most commonly see us refer to these as simply "algorithms".
All of our lead-acid algorithms have three stages: Bulk, Absorption, and Finish as illustrated below (not necessarily to scale of charge time):
Bulk: In this phase most of the energy is returned to the battery by the charger in maximum power or current mode. Normally, a conservative target voltage is selected to exit bulk.
Absorption: This is a constant voltage phase to allow the battery to naturally "absorb" current and taper down as the lead plates begin to recharge more fully.
Finish: In our more cyclic applications it is necessary to use a constant current finish to complete charging in a reasonable amount of time. This current level MUST be suitable for the size of the battery per the manufacturer's specification. Here the last parts of the plates are restored until the battery is fully recharged.