Specific Gravity Of Electrolyte
- Measure specific gravity of electrolyte using a hydrometer and a thermometer. Specific gravity varies with temperature of electrolyte, so it must be corrected for 20°C (68°F) using the following calculation:
S 20 = St + 0.0007 x (t - 20)
S 20 : Specific gravity corrected at electrolyte temperature of 20°C (68°F)
St: Measured specific gravity
t: Measured temperature (°C)
Determine whether or not battery must be charged, according to the corrected specific gravity.
Standard specific gravity: 1.220 - 1.290 [at 20°C (68°F)]
- Measuring the specific gravity of the electrolyte in the battery will disclose the state of charge of the battery. The relation between specific gravity and state of charge is as shown in the figure.