Specifications

MARATHONNORCO AEROSPACE, INC.
NICKEL-CADMIUM AIRCRAFT BATTERIES
24-34-00
Page 1401
MAY 10/11
14.0 STORAGE
14.1 Inactive Storage
Inactive storage is where the battery is stored for long periods of time. The battery should be stored in a
completely discharged, shorted out condition. (See Section 8.1). Nickel-cadmium batteries may be stored
in a non-corrosive atmosphere for an unlimited period at temperatures ranging from -65° to + 120°F; the
upper limit may be extended to + 160°F for up to two weeks.
14.2 Active Storage
Active storage is where a fully charged battery is stored temporarily prior to going into service. Nickel-
cadmium batteries will incur only a temporary loss of capacity during active storage. The charge retention
depends largely on the ambient temperature in which the battery is stored and the length of time in
storage. Charge retention is also affected by impurities in the electrolyte and electrical leakage from cells
to battery case. Storage at higher temperatures will result in a greater loss of charge; at low
temperatures, this loss will be much less.
Before placing a battery into active storage, the battery should be fully serviced and cleaned. Where
operation is required immediately after removal from active storage, proper cleaning is even more
important to avoid the possibility of contaminants creating conductive paths within the battery case and
increasing the self-discharge rate.
A properly serviced battery can be stored at temperatures between 60°F and 80°F for up to 90 days.
Beyond this time or temperature the battery should be serviced before being placed into service.
14.3 Extending Active Storage Shelf Life
If the battery is to be placed into an active storage condition, for longer periods, the battery should be
serviced then maintained in a fully charged condition by trickle charging, thus compensating for the
normal self discharge that occurs in the battery. Trickle charge rates are given in table 4 of this manual.
Batteries stored under this condition must be kept at a temperature between 60°F and 80°F. Maximum
trickle charge time prior to placement into service is one year. Beyond this time or temperature the
battery should be serviced before being returned to active storage or being placed into service.
NOTE: Trickle charge rates are critical. Charging at a rate greater or less than the
recommended rate can create significant problems.