Lucent Technologies KS-20472 - Lead-Sulfate Crystals; From Initial Charge to Service

Lucent Technologies Round Cell Batteries
Issue 3 December 1999 Installation 6 - 21
Initial Charging, continued
Lead-sulfate
Crystals
The absence of lead-sulfate crystals on the positive plate is an indication
that the initial charge is completed. After a satisfactory initial charge, no
lead-sulfate crystals or gray coloration should be visible on the vertical
positive plate columns when examined with a flashlight. Hold the
flashlight close to the jar wall at an angle of approximately 45 degrees.
The lead-sulfate crystals appear as sparkling diamond-like reflecting
particles or as a gray coloration.
The vertical columns should be black or dark brown and totally free of
any diamond-like lead-sulfate crystals or gray coloration. The
disappearance of lead-sulfate crystals normally occurs in three distinct
phases:
• Phase 1: black and crystalline
• Phase 2: gray and lightly crystalline
• Phase 3: black or dark brown and crystal free.
The disappearance of lead-sulfate crystals or gray coloration occurs
from top to bottom during initial charge. To insure total absence of
lead-sulfate crystals or gray coloration, concentrate inspection for
crystals at the bottom of the positive plate vertical columns.
After return to float following the initial charge, cells should be floating
in the range of the average applied voltage ±0.05 volt. Cells which are
not free of lead-sulfate crystals after the initial charge may be shorted. If
some cells are still crystalline after initial charge, continue the battery
string on initial charge at 2.5 to 2.55 volts for a total charge time not to
exceed 250 hours. If charging fails to clear the lead-sulfate crystals
within 250 hours, report the cells to Lucent Technologies.
From Initial
Charge To Service
From initial charge to service, maintain battery plant voltage at
2.17-2.20V/cell. After at least 7 days on float and within a week before
service, inspect all cells and record the presence or absence of
lead-sulfate crystals. Measure and record the cell voltage. If any cell is
heavily crystalline and reads 2.09 volts or less, it may be shorted and
should be reported to Lucent Technologies. If any cell is crystalline and
voltage measurement reads greater than 2.09 volts, give that cell an
individual boost charge at approximately 2.5 volts until it is clear of the
crystals.