BoatHowTo · video

What this video covers

Jan Attenstedt and Nigel Calder explain the risks of paralleling batteries with mismatched amp-hour capacities.0:12 While theory suggests batteries in parallel share electrical loads proportionally to their capacity, internal resistance variations prevent this in practice.0:56 One battery inevitably works harder than the other, leading to system imbalance and premature degradation of the entire bank.1:10 For long-term reliability on a cruising boat, all batteries in a parallel bank must share the same make, model, age, and manufacturing batch.1:33 While mixing capacities may function temporarily during an emergency, it significantly shortens the service life of the installation.1:30 Proper wiring geometry remains essential to maximize battery longevity, a topic covered in the BoatElectrics 101 course at BoatHowTo.com.2:49 Matching battery specifications ensures balanced discharge cycles and prevents unnecessary strain on individual cells.

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