Battery & Charging System

Open-circuit voltage and charging system reference for 12V flooded lead-acid batteries. Voltages measured at rest, no load, at least 4 hours after charging or driving.

Open-Circuit Voltage ↔ State of Charge (12V flooded lead-acid)

VoltageState of ChargeSpecific Gravity
12.65 V or higher100% (fully charged)1.265
12.45 V75%1.225
12.24 V50%1.190
12.06 V25%1.155

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