The Marinervideo
Lithium Batteries On Boats Are Not Dangerous - Ignorance Is.
13 April 2026 · 27 min · 15K views · North Atlantic Ocean
Sailboat bow cuts blue ocean under clear sky
What this video covers
Chris, sailing solo through the Azores High aboard The Mariner, experiences a full BMS shutdown on his two Li-Time 24-volt, 100 Ah lithium iron phosphate batteries after they drop to 22.75 volts — well below his usual 26.2 V charging threshold — while he was distracted servicing a batten box and troubleshooting an autopilot fault.4:32 The BMS shutdown also explains the autopilot's erratic solenoid behavior he noticed first.1:41 He explains the correct recovery procedure: feed a low solar charge voltage through a Renogy charger (three panels in series, ~60 V input) to slowly raise battery voltage until the BMS reopens, rather than engaging the alternator against a closed BMS, which risks blowing the alternator or damaging the BMS.5:42 He distinguishes lithium iron phosphate (LiFePO4) from lithium-ion chemistry, arguing the former is stable enough for marine use while the latter — as used in EV packs like the Nissan Leaf — is not.2:52 Key warnings: never parallel a depleted LiFePO4 bank with a charged one; use only battery switches with a neutral position between banks; T-style fuses (250 A) are essential protection.10:46 He recommends a low-voltage alarm on the Victron monitor he recently installed to replace a Renogy unit, and suggests DC-to-DC charging through a lead-acid buffer as the safest alternator-to-lithium setup.14:20 Ignorance of BMS behavior, not the chemistry itself, is the primary danger with LiFePO4 aboard.
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