A. Lack of Gassing:
Lack of gassing while on charge may indicate an internal short between plates, i.e., the cell discharges internally as fast as it is being charged.
B. Specific Gravity or Voltage:
Specific gravity or voltage of a cell lower than other cells is an indication of excessive internal losses and may result from consistent undercharging.
C. Color:
Color or appearance of plates or sediment different from other cells is addressed below:
- Patches of white lead sulfate on either the positive or negative plates: caused by standing idle or undercharging for extended periods
- Antimony deposit dark-slate patches on negative plates: caused by charging at too high a rate or an aged cell nearing the end of its service life.
- Top layer of sediment white: caused by undercharging.
- Lumpy brown sediment: caused by overcharging.
- All white sediment no visible layers: caused by overcharging after prolonged low float voltage.
- Large flaking on the interplate collector bar: caused by being on float charge for extended periods at insufficient float voltage without equalizing charging being performed.
D. Plate Problems:
If any checks below are excessive, capacity tests must be run to determine if individual cells or the entire battery should be replaced.
- Cracks on the edges of the positive plate grids.
- Light-colored sulfating spots on edges of plates below cracks mention.
- Excessive sediment in the bottom of the case.
- “Mossing” or “treeing” on the tops of negative plates.
E. Water:
- Cell uses excessive water: caused by excess charging rates, high operating temperatures, or leaking cell.
- Cell requires very little water: caused by insufficient charging.
F. Buckling of Plates:
Buckling of positive plates indicates excessive sulfation caused by undercharging or excessive temperature.
G. Failure to Supply Rated Ampere-Hour Loads:
Failure to supply rated ampere-hours indicates discharged condition, excessive sulfation, or loss of active material from positive plates. Cells may be worn out or active material may be gone from positive plates.