Is a Voltage of 11.8 Dangerously Low for My AGM Battery?
22 December 2020 · 4 min · 61K views
What this video covers
An AGM battery bank voltage of 11.8 volts, corresponding to a 30% state of charge or 70% depth of discharge, is not inherently dangerous for the battery.0:50 While deeper discharges reduce the total cycle life of lead-acid batteries, the primary risk at low voltage levels is not battery damage but rather equipment failure due to voltage drop.1:52 If a boat’s electrical system features undersized wiring or poor-quality crimps, loads located far from the battery bank may experience voltage levels significantly lower than the 11.8 volts measured at the terminals.2:08 Proper wiring ensures that equipment continues to function correctly even when the battery bank is depleted.2:22 Boaters should prioritize using their available battery capacity rather than strictly limiting discharge to 80% or 90% to preserve cycle life.2:46 Using batteries down to 30% capacity is a practical choice for many systems, including AGM and Firefly battery banks.3:12
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