Charging a battery is a simple task. You connect the
Ensure that the charging area is well
charger cables to the proper terminals, turn the charger
ventilated. Hydrogen gas released by batteries on
on, and set the timer. The charger will turn itself off at
charge is highly explosive. Do not allow smoking
the proper time. Here is the procedure for charging a
in the vicinity of batteries being charged.
1. With the battery out of the vehicle, clean and
inspect it thoroughly. Remove any corrosion present by
using a solution of bicarbonate of soda and water.
Discharge takes place in batteries even when they
(Ensure that none of the solution enters the cells.)
are not in use. The rate of discharge varies with
Check the case of the battery for cracks and breaks.
temperature and specific gravity of the electrolyte.
Self-discharge changes the specific gravity of the
2. Remove the vent caps and inspect the battery
electrolyte just as normal discharge does. Inactive,
internally. If the electrolyte level is low, add distilled
charged batteries should be stowed in a cool, dry place
water (or drinking water if distilled water is not
to reduce self-discharge. After a battery has been
available). Bring the level of the electrolyte to about
activated, the state of charge should be checked
three-eights of an inch above the plates or to the level
periodically (whether in use or not) and recharged
specified by the battery manufacturer. Place the vent
when necessary. A battery is damaged if it is allowed to
caps in the cell openings, but do not tighten them down.
remain in a discharged condition. A good charge is
(The vent caps keep electrolyte from spraying out of the
especially important in cold weather to prevent
cells during charging and keep foreign material out of
freezing. A battery that is completely discharged
freezes at about 18°F; a battery that has a specific
3. Connect the battery to the charger. Ensure that
gravity of 1.260 freezes at about -75°F.
the positive cable is connected to the positive terminal
and the negative cable is connected to the negative
PLACING IN SERVICE
terminal. Turn the charger on.
New batteries may be received full of electrolyte
and fully charged. In this case, all that is necessary to
make them ready for service is to properly install them
in the equipment. Most batteries, however, are received
Always connect the battery to the charger
"dry and charged."
before turning on the charger, and disconnect the
Dry-charged batteries retain their state of full
battery only after turning off the charger. This is to
charge indefinitely so long as moisture is not allowed to
preclude the possibility of creating a spark, which
enter the cells. Therefore, dry-charged batteries should
could cause an explosion.
be stowed in a cool, dry place. When moisture and air
enter the cells, it causes the negative plates to oxidize
4. When the battery is fully charged, the charger
and lose their charge. If dry-charged batteries are al-
will shut off. Remove the battery cables, tighten down
lowed to stay in this condition for a long period of time,
the vent caps, and place the battery in storage or back in
damage results. Dry-charged batteries must be ac-
tivated and recharged before you place them in service.
Take frequent hydrometer and temperature
Activating a Dry-Charged Battery
readings of each cell and record them. The specific
gravity can be expected to rise during the charge. If the
To activate a dry-charged battery, remove the vent
specific gravity does not rise, the battery is bad and
restrictors from the vent caps and remove the vent caps.
should be disposed of. Keep a constant watch for
Fill all the cells to the proper level with electrolyte that
excessive gassing. This is especially important when
has a specific gravity of 1.275 or as specified by the
you use the constant current method of charging. Be
battery manufacturer. Best results are obtained when
especially watchful at the very beginning of the charge
the battery and the electrolyte are at a temperature
when you use the constant voltage method. Reduce the
between 60°F and 80°F, but in no case should the
charging current or voltage if excessive gassing takes
temperature of the electrolyte exceed 90°F. Some