such as glass or earthenware because they may crack
gassing occurs while filling the battery, due to the
due to the heat generated during the mixing operation.
release of carbon dioxide (a product of the drying
process) or hydrogen sulfide (caused by the presence of
Always pour acid into water slowly, stirring
free sulfur). These gases and odors are normal and are
constantly but gently. Never pour water into con-
no cause for alarm.
centrated acid. The resulting chemical reaction will
Allow the battery to stand for at least 1 hour after
generate heat so rapidly that the solution may boil and
filling it with electrolyte. If at the end of 1 hour the level
splash out of the container.
of electrolyte has fallen, add more electrolyte to restore
Be alert for sprays and splashes when you open a
it, and replace the vent caps. If electrolyte is spilled on
container or during mixing. If acid spills, neutralize it
the battery, it should be removed. Use a solution of
with bicarbonate of soda or ammonia and flush with an
bicarbonate of soda and water, and be careful not to
abundance of water.
allow the solution to get into the cells. The exterior of
the battery should then be flushed with fresh water.
If acid is spilled or splashed on any part of your
body, neutralize it with a solution of bicarbonate of
soda and water or ammonia and water. Immediately
shower or flush the affected areas with large amounts of
A new battery should be given an initial charge in
water. Should your eyes be affected, flush with an
accordance with the manufacturer's instructions. In the
abundance of fresh water and seek medical attention
absence of instructions, the initial charge should be
given at the rate of 1 ampere per positive plate per cell.
Ensure that an adequate supply of first aid
Charging should continue until the specific gravity of
material is on hand at all times for neutralizing acid.
all cells shows no increase over a period of 2 hours. If
the temperature of the battery exceeds 100F, stop the
Do not carry electrolyte in open-top containers,
charge and allow the battery to cool.
and ensure that glass containers are protected against
Adjusting Specific Gravity
Never allow containers of electrolyte to be
Usually, no adjustment of the specific gravity is
placed near heating pipes or to stand in the sun for any
necessary. However, if the specific gravity should
length of time.
exceed 1.300 in any cell, it should be reduced to some
Allow mixed electrolyte to cool to room
level between 1.275 and 1.300. You can reduce the
temperature before adding it to battery cells. Do not add
specific gravity by removing a small amount of
electrolyte to the battery if its temperature is above
electrolyte with a hydrometer syringe and replacing it
90F. Hot electrolyte can destroy the cell plates very
with distilled or drinking water.
Safe Handling of Electrolyte
After you fill the battery cells, allow the
electrolyte to cool again. Remember that more heat is
Although a premixed electrolyte is usually
generated by its contact with the battery plates.
available for servicing dry-charged batteries, you may
be required to use concentrated sulfuric acid. If so, the
MAINTENANCE AND TESTING
sulfuric acid must be mixed with pure water to obtain
the proper specific gravity for electrolyte.
Battery maintenance and testing should always
begin with a thorough visual inspection. Look for signs
Mixing electrolyte is dangerous. Concentrated sul-
of corrosion on or around the battery. Clean the top of
furic acid can burn clothing, and if it comes into contact
the battery with a stiff bristle brush, being careful that
with your skin or eyes, severe burns may result. You
particles brushed off do not get on your skin or clothing.
must observe the following safety precautions when
Wipe the top of the battery with a cloth moistened with
working with concentrated sulfuric acid or electrolyte.
either ammonia or baking soda dissolved in water.
Wear approved goggles, gloves, aprons, and
Remove the cables and inspect the terminal posts to
see if they are deformed or broken. Clean the terminal
Use a lead-lined tank or a heavy plastic
posts, and clean the inside surfaces of the cable clamps
container to mix the electrolyte. Do not use materials
before replacing them on the terminal posts. Inspect the