Battery Diagnosis Without Exp-800 NI Or Gr8-1200 NI: SULFATION
- A battery will be completely discharged if it is left unattended for a long time and the specific gravity will become less than 1.100. This may result in sulfation on the cell plates.
- To determine if a battery has been "sulfated", note its voltage and current when charging it. As shown in the figure below, less current and higher voltage are observed in the initial stage of charging sulfated batteries.
- A sulfated battery may sometimes be brought back into service by means of a long, slow charge, 12 hours or more, followed by a battery capacity test.
Courtesy of NISSAN NORTH AMERICA, INC.