Lead-Acid Batteries

Specific gravity and charge of lead acid batteries - temperature and efficiency.

State of Charge (%)Voltage (V)Specific GravityStatus
10012.71.3Fully Charged / Overcharged
7512.51.25Normal
5012.21.2Half Charged
2511.91.15Very Low Capacity
011.81.12Discharged
-10011.5<1.12Severely Discharged

Voltage and Specific Gravity vs. State of Charge (SOC)

The table above shows the relationship between state of charge and key battery parameters:

  • Overcharged: Specific gravity above 1.30
  • Very Low Capacity: Specific gravity ranging 1.13 - 1.15
  • Discharged: Specific gravity below 1.12

Battery Efficiency vs. Temperature

Lead-acid battery efficiency varies significantly with temperature. Higher temperatures generally improve performance, while colder temperatures reduce efficiency.

Specific Gravity vs. Temperature

Specific gravity in a fully charged lead acid battery varies with temperature. Temperature compensation may be necessary for accurate state of charge determination.