-
Inspect the cell for damage, Read
Warning Label On Cell Before Proceeding.
-
Remove vent caps, fill each cell above the top of the
splash guard (protection mat covering separators) with
approved 1.265 specific gravity battery grade electrolyte.
-
Keep sparks and flames away from battery at all times.
Allow electrolyte to saturate plates and separators for 30
minutes. Temperature of electrolyte will rise and specific
gravity will drop. Add electrolyte if not visible. Check
for correct polarity with a voltmeter.
-
Place on charge at the finishing rate (5% of the 8 or 20
hour rate). The rate may be increased if the battery does
not begin to gas. Do not let the cell temperature exceed
115° F (46° C) If the temperature becomes excessive or the
cells begin to gas vigorously, reduce the rate of charge.
Continue charging until the cell (or cells) reach within
.005 points of the specific gravity of the filling
electrolyte corrected for 77° F (25° C)
-
Top up or remove electrolyte as necessary for proper
level. Never add electrolyte (only approved water) after
activation.
-
Replace vent caps and remove any spillage of electrolyte.
If necessary clean with bicarbonate of soda and water (
100 grams of soda to one liter of water) Rinse with water
and wipe dry. Insure that soda solution
does not get into cells.
Shelf life of a dry charge battery is five years plus. Store
in a cool dry area. The positive plate has an unlimited
shelf life. The negative plate will revert to lead oxide
when in the presence of water and oxygen. If this should
happen, the battery is not ruined,
but activation will take considerably longer!
The electrolyte temperature will rise dramatically during
activation. Do not place on charge until the temperature
drops below 115° F. Activation may take
several days!
Before installing the batteries, clean the contact surfaces
of the lead terminal post and battery terminals with a wire
brush. Apply a thin coat of Vaseline to all contact points
and connector bolts. After all connections have been
securely tightened, they should be gone over and tightened a
second time.
Preventive Maintenance (for more information see bulletin
#509)
-
Check the height of the electrolyte twice a month. If
necessary replace with approved water only. Many times
domestic water is satisfactory. Water with a high mineral
content is not satisfactory.
-
Do not use water that is difficult to create a lather when
washing your hands with soap and water.
-
Never fill the cells above the bottom of the vent well.
Over filling will cause loss of electrolyte and reduce the
battery capacity.
-
Never add acid to the battery.
(Only during activation)
-
Avoid over discharging of the battery as the useful life
will be reduced. The rule of thumb is not to exceed 80
percent of the capacity of the battery. On a 12 volt
system this would be approximately 11 volts. Remember over
discharging or low voltage will also reduce the life of
most electrical equipment.
-
Battery capacity is based on each cell having an
electrolyte temperature of 77° F (25° C). Temperatures
below 77° F reduce the battery's effective capacity and
lengthen the time to restore to full capacity.
Temperatures above 77° F will slightly increase capacity,
but will also increase self discharge and shorten battery
life.
The state of charge of a battery can be measured with a
hydrometer. The chart below shows the approximate
"percent of charge" corrected for
temperature at various specific gravity values.
|
Charged |
Specific Gravity |
Open Circuit Voltage |
|
100% |
1.265-1.275 |
12.6 |
|
75% |
1.225-1.235 |
12.4 |
|
50% |
1.190-1.200 |
12.2 |
|
25% |
1.155-1.165 |
12.0 |
|
0% |
1.120-1.130 |
11.7 |
Determining state of charge by voltage is more difficult as
there must be no load or surface voltage present.
When taking specific gravity measurements, it is important
to correct for temperature to get a true reading. As a rule
of thumb, specific gravity will change by 0.003 for each ten
degrees Fahrenheit change in temperature above or below 77°
F (25° C). Below 77° F subtract from readings and above 77°
F add to the readings. As an example a reading of 1.250 at
67° F corrected for temperature would be 1.247 and a reading
of 1.250 at 87° F corrected for temperature would be 1.253.
It is recommended that fully charged gravity and voltage
readings be taken of each cell every month and compared with
readings from the preceding period. The readings will
indicate any marked difference in battery condition as well
as differences between cells. A good rule of thumb is if
there is 0.025 points or less between the high and low cell
the battery is not defective. Low readings would indicate
the battery being discharged.
The charging system can have a profound effect on the life
of the battery. A high voltage setting can cause excessive
gassing and water loss. Eventual damage to the battery
system will take place. A low setting will leave the
batteries in an under charged condition resulting in a loss
of capacity and eventually the battery system may not take a
charge. A proper setting will result in a minimum of water
consumption and still able to maintain the batteries at full
charge.
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