Reversing Entropyvideo
This WILL DESTROY ALL ELECTRONICS aboard your SAILBOAT !
August 6, 2025 · 12 min · 66K views
What this video covers
Replacing lead-acid batteries with lithium-ion batteries without proper system integration can destroy marine electronics.▶ 0:07 When a lithium battery’s internal Battery Management System (BMS) detects an overvoltage condition, it disconnects the battery from the electrical system.▶ 2:33 If an alternator is running at that moment, the sudden loss of the battery load causes a voltage spike that can fry connected devices, including chart plotters, radar, and autopilots.▶ 3:55
To prevent this, sailors should use one of three methods.▶ 7:47 A DC-to-DC converter isolates the lithium bank from the alternator, maintaining a lead-acid battery as a constant load.▶ 7:49 Alternatively, keeping a lead-acid battery in parallel with the lithium bank ensures the alternator always sees a load, though this requires careful voltage matching.▶ 8:38 The most robust solution involves installing an external voltage regulator that monitors alternator temperature and communicates directly with the lithium BMS to throttle or shut down the alternator before the battery disconnects.▶ 10:38 While Victron offers repairable components for some fried electronics, other manufacturers like B&G often provide no serviceability for damaged boards.▶ 5:03
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