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How to Charge a Deep Cycle Battery Properly

Two-part video series on battery charging terminology, concepts, and techniques.

In part 1 we cover some basic terminology and concepts for lead acid and lithium deep cycle batteries that are useful for understanding how to properly charge them, including:

  • How deep cycle batteries differ from car batteries
  • Battery capacity – amp-hours (Ah) and Watt-hours (Wh)
  • Battery condition – state of charge (SoC) and depth of discharge (DoD)
  • Deep cycle battery charging stages – bulk, absorption, float, and equalize

In part 2 we go into greater depth on charge rates for deep cycle batteries, including examples using both lead acid and lithium. We’ll also explain why charge rate is so important for designing a battery-based solar power system. Correction: At 2:38 in this video we made a math error. 0.2C Rate should be 0.05C.