WARNING
battery voltage drops to a value equal to 1.75 times the
number of cells in series or the voltage of any individual
cell drops to 1.65 volts. Keep the rate of discharge
A mixture of hydrogen and air can be
constant throughout the test discharge. Because
dangerously explosive. Do not permit
standard batteries are rated at the 10-hour capacity, the
smoking, electric sparks, or open flames near
discharge rate for a 100 ampere-hour battery is 100/10,
charging batteries.
or 10 ampres. If the temperature of the electrolyte at
the beginning of the charge is not exactly 80F, correct
the time duration of the discharge for the actual
TREATMENT OF ACID BURNS
temperature of the battery.
A battery at 100 percent capacity discharges at its
If acid or electrolyte from a lead-acid battery comes
10-hour rate for 10 hours before reaching its
into contact with the skin, wash the affected area as soon
low-voltage limit. If the battery or one of its cells
as possible with large quantities of fresh water.
reaches the low-voltage limit before the 10-hour period
Afterwards, apply a salve, such as petrolatum, boric
acid, or zinc ointment. If none of these salves are
has elapsed, discontinue the discharge immediately and
available, clean lubricating oil will suffice. When you
determine the percentage of capacity using the
following equation:
wash the area, use large amounts of water. A small
amount of water might do more harm than good and
spread the acid burn. You can neutralize acid spilled on
clothing with diluted ammonia or a solution of baking
soda and water.
Where:
C = percentage of ampere hour capacity available
SUMMARY
Ha= total hours of discharge
Ht = total hours for 100 percent capacity
The information included in this section is an
introduction to the operation and use of lead-acid
For example, a 100-ampere-hour, 6-volt battery
storage batteries aboard ship. For in-depth coverage,
delivers an average current of 10 amperes for 10 hours.
you should refer to Naval Ships' Technical Manual,
At the end of this period, the battery voltage is 5.25 volts.
chapter 313.
On a later test, the same battery delivers an average
current of 10 amperes for only 7 hours. The discharge
was stopped at the end of this time because the voltage
BATTERY CHARGERS
of the middle cell was found to be only 1.65 volts. The
percentage of capacity of the battery is now 7/10 x 100,
The U.S. Navy uses numerous types and styles of
or 70 percent. Thus the ampere-hour capacity of this
battery chargers. A battery charger is designed to
battery is reduced to 0.7 x 100 = 70 ampere-hours.
replace the electrical energy a lead-acid storage battery
has consumed (lost) while being used. The battery
Record the date for each test discharge on the
charger is essentially a regulated, constant supply with
storage battery record sheet.
adjustable outputs, current, and voltage. The battery
charger discussed in this chapter is the 24-302-BN-1
BATTERY GASSING
Battery Charger.
When a battery is being charged, a portion of the
DESCRIPTION OF THE 24-302-BN-1
energy is dissipated in the electrolysis of the water in the
BATTERY CHARGER
electrolyte. Hydrogen is released at the negative plates
and oxygen at the positive plates. These gases bubble
The model 24-302-BN-1 battery charger is
up through the electrolyte and collect in the air space at
designed to operate with an input voltage of 115 volts
the top of the cell. If violent gassing occurs when the
ac 5 percent, at 60 Hz 5 percent, single-phase, 20
battery is first placed on charge, the charging rate is too
amperes. The output is determined by the number of
high. If the rate is not too high, steady gassing, which
cells selected to be charged (3, 4, 6, 12, or 18) and the
develops as the charging proceeds, indicates that the
current rating selected (2, 8, 15, or 30 amperes).
battery is nearing a fully charged condition.
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