BATTERY CHARGING RATE
condition. Observe the following steps when giving a
Normally, the charging rate of Navy storage
1. Determine the starting and finishing rate from
batteries is given on the battery nameplate. If the
the nameplate data.
available charging equipment does not have the desired
charging rates, use the nearest available rates. However,
2. Add water, as necessary, to each cell.
never allow the rate to be so high that violent gassing
3. Connect the battery to the charging panel and
make sure the connections are clean and tight.
4. Turn on the charging circuit and set the current
through the battery at the value given as the
5. Check the temperature and specific gravity of
pilot cells hourly.
6. When the battery begins togas freely, reduce the
BATTERY CHARGING TIME
charging current to the finishing rate.
A normal charge is complete when the specific
Continue a charge until the battery is fully charged.
gravity of the pilot cell, corrected for temperature, is
Take frequent readings of specific gravity during
within 5 points (0.005) of the specific gravity obtained
the charge. Correct these readings to 80°F and
on the previous equalizing charge.
compare them with the reading taken before the
battery was placed on charge. If the rise in specific
gravity in points per ampere-hour is known, the
Battery Equalizing Charge
approximate time in hours required to complete the
charge is as follows:
An equalizing charge is an extended normal charge
at the finishing rate. It is given periodically to ensure
all the sulfate is driven from the plates and all the cells
are restored to a maximum specific gravity. The
equalizing charge is continued until the specific gravity
of all cells, connected for temperature, shows no change
for a 4-hour period. For an equalizing charge, you must
TEST DISCHARGE OF BATTERIES
take readings of all cells every half hour.
The test discharge is the best method for you to
Battery Floating Charge
determine the capacity of a battery. Most battery
switchboards are provided with the necessary
You can maintain a battery at full charge by
equipment for you to perform test discharges to
connecting it across a charging source that has a voltage
batteries. If proper equipment is not available, a tender,
maintained within the limits of 2.13 to 2.17 volts per cell
a repair ship, or a shore station may perform the test
of the battery. In a floating charge, the charging rate is
discharge. A battery test discharge is required when one
determined by the battery voltage, rather than by a
of the following conditions exists:
definite current value. The voltage is maintained
1. A functional test reveals a low output.
between 2.13 and 2.17 volts per cell with an average as
close to 2.15 volts as possible.
2. One or more cells are found to have less than
normal voltage after an equalizing charge.
Battery Emergency Charge
3. A battery cannot be brought to within 10 points
of normal charge of its specific gravity.
An emergency charge is used when you must
4. A battery has been in service 4 years.
recharge a battery in the shortest possible time. The
Always precede a test discharge by an equalizing
charge starts at a much higher rate than is normally used
charge. Immediately after the equalizing charge,
for charging. Use it only in an emergency, as this type
discharge the battery at its 10-hour rate until the total
of charge may be harmful to the battery.