BoatHowTo · video

What this video covers

Jan Attenstedt and Nigel Calder outline methods for identifying capacity loss in lead-acid battery banks.0:05 Monitoring amp-hours in and out via a systems monitor provides a baseline for comparing current voltage levels against historical performance at specific discharge states.0:55 For a definitive assessment, perform a controlled discharge test by fully charging the battery and then draining it until the voltage reaches 10.5 volts.1:02 Maintain a discharge rate between 5% and 10% of the battery's rated amp-hour capacity to ensure accurate results.1:37 Avoid discharging lead-acid batteries to zero volts, as this causes permanent damage.1:25 While this test stresses the battery, it serves as a necessary diagnostic step before embarking on a long cruise to verify that the bank can meet power demands.1:38 Lithium-ion batteries generally maintain consistent capacity over their life cycles, making this testing procedure primarily relevant for lead-acid systems.0:28

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