The battery is charged with a current of 5.5 A with the plugs turned out. Charging is carried out before the onset of abundant gas evolution and the achievement of a constant voltage and density of the electrolyte for 3 hours. The density of the electrolyte of a charged battery at 25°C should correspond to the data in Table. 10.2 for each climatic region.
When charging the battery, periodically check the temperature of the electrolyte and do not allow it to rise above +40°C. When the temperature reaches +40°C, reduce the charging current by half or interrupt charging and cool the battery down to +27°C.
Charging is stopped when abundant gas emission from all battery cells begins, and the voltage and density of the electrolyte during the last three measurements (carried out 1 hour after disconnecting the battery) will remain constant.
If at the end of charging the density of the electrolyte (determined taking into account the temperature correction) differs from that indicated in the table. 10.2, correct it. With increased density, remove some of the electrolyte and add distilled water. If the density of the electrolyte is below normal, then remove it from the cell and add electrolyte of increased density (1.4 g/cm3).
After adjusting the density of the electrolyte, continue charging the battery for another 30 minutes to mix the electrolyte. Then disconnect the battery and after 30 minutes measure the electrolyte level in all cells. If the electrolyte level is below normal, add electrolyte, the density of which corresponds to the given climatic region (see table. 10.2). If the electrolyte level is above normal, remove excess electrolyte with a rubber bulb.
Table 10.2. Electrolyte density at 25°С, g/cm3
