TM 11-6140-203-14-4&P
5. If batteries are discharged at a
low state of charge or in a discharged condition.
higher rate than give in (1) above, refer to paragraph 4-
When the battery is recharged, the electrolyte
level rises and reaches its maximum height at
14 applicable capacity at the specific rate.
full charge. Ideally the electrolyte level should be
6 If all cells are 1 volt or greater, stop
checked on a fully charged battery that has been
discharging and proceed to final charge.
at rest for a minimum of 30 minutes to a
(2) Final charge. Perform final charge in
accordance with (a), (b) or {c} below depending on
maximum of 2 hours before checking the
electrolyte level. If the 2-hour time is exceeded
equipment available.
before the level of the electrolyte is checked, the
(a) The ANIUSM-432 will recharge the
battery must be brought back up to full charge
battery for 1 hour and then shut off. Cell voltage checks
state and allow to rest again before performing
and electrolyte level adjustments should then be made
the check. The maximum rest time must be
before the battery is placed in service.
strictly adhered to. After the battery has been
(b) The RF80GT will recharge most
removed from the battery charger, it will
batteries in one hour and then shutoff providing a Battery
discharge gases trapped between the separators
OK indication if more than 60 minutes was obtained on
and plates during the rest period. As this
the performance test.
Cell voltage checks and
progresses, electrolyte solution is absorbed into
electrolyte level adjustments should then be made before
the battery plates in place of the gases. If the
the battery is placed in service Do not start final charge if
battery has rested longer than the maximum
battery temperature exceeds 104' F for cellophane
period of time, absorption could bring the
separated batteries, or 120' F for Permion or Celgard
electrolyte level to the point that inspection would
separated ones. Wait until battery has cooled to ambient
indicate that more should be added. Correction
temperature before finishing change and placing in
of the electrolyte level under these conditions
service.
could overfill the cell and cause spewing when
(c) Constant potential or constant
the battery is brought to a full charge while
current charging should be performed in accordance with
installed in the equipment for service. The
correct level of electrolyte is 1/4 inch above the
(3) Battery rest. Allow battery to rest for 30
top of the plates of a fully charge cell that has
minutes before adjusting electrolyte level (para 5-5).
been at rest as specified paragraph 5-4g. The
(4) Electrical leakage.
Perform electrical
procedure for checking the electrolyte level is
leakage test 95 specified in paragraph 4-10.
exactly the opposite of that for lead-acid
batteries in which the electrolyte level is adjusted
5-5.
Electrolyte Level Adjustment
by adding water before placing the battery on
CAUTION
charge, or whenever the electrolyte level is low.
For batteries requiring electrolyte adjustment, be
The maximum electrolyte level for a nickel-
sure to perform the charging procedures given in
cadmium battery is one-fourth inch above the top
paragraph 5-4f first. These procedures must be
of the plates. Perform the following procedures
followed to prevent overfilling cells. Overfilling
for electrolyte adjustments:
will cause spewage of electrolyte resulting in
a. Before using the syringe, if necessary, modify it
damage to the battery. Do not adjust electrolyte
as follows:
level after a battery has discharged. The correct
(1) Use a sharp pin that has been heated with
electrolyte level cannot be determined when the
a flame to pierce the stem of the syringe one-fourth inch
battery has been discharged. Conversely, never
from the bottom of the stem (A, fig. 5-2).
allow electrolyte to fall below the top of the plates
(2) Let the pin remain in the. stem for 2 or 3
when battery is in a charged condition. Low
minutes and then withdraw the pin slowly from the stem.
electrolyte level in the charged condition will
b. Remove the fillercaps with the nylon wrench.
cause the cells to heat up, resulting in their
destruction.
NOTES
An inherent characteristic of nickelcadmium
battery cells is that the electrolyte is absorbed
within the plates and separators to a point where
it is not visible from the top of the cells when at a
5-6
