A vented, rechargeable nickel cadmium aircraft batteries and cells and harnesses used therein.

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MIL-PRF-49450B(CR)

3.3.1 Metals. External metal or component parts of each battery, cell and harness shall

show no evidence of cracking, chipping, scaling, corrosion or other deleterious effects when

exposed to 1.300 � 0.025 specific gravity KOH electrolyte solution.

3.3.2 Plastic materials. Plastic materials used in each battery, cell and harness shall show

no evidences of cracks, blisters or other deterioration and shall not change more than 2.5 percent

in weight or 2.0 percent in any dimension when exposed to 1.300 � 0.025 specific gravity KOH

electrolyte solution.

3.3.3 Elastomer materials. All elastomer materials used in each battery, cell and harness

shall show no evidence of cracks, blisters or other deterioration after being exposed to 1.300 �

0.025 specific gravity KOH electrolyte solution. Materials of pads, gaskets and O-rings shall be

selected to provide adequate seal and minimize compression set when tested in accordance with

4.5.3.

3.4 Components. The battery, cells, and harness shall conform to this specification and

specification sheets.

3.4.1 Batteries.

3.4.1.1 Battery container and cover. The battery container and cover shall be of alkali-

resistant high strength material, free of rough spots, pits, blowholes and other deformations. The

container and/or cover shall be completely coated by an epoxy resin to a minimum thickness of

0.015 � .008 inches to prevent absorption of electrolyte. The dimensions and location of

receptacles hold-downs, latches, latch hooks, vent tubes, name and instruction plates, and

carrying strap shall conform to the applicable specification sheets. The cover shall be fitted with

a hold-down pad having an integral elastomer gasket positioned so as to match the rim of the

container body for a gas-tight fit between the cover and the container body. The seal shall

prevent the loss of pressure in excess of 2.75 inches of water when tested in accordance with

4.5.8.

3.4.1.2 Latches. The cover shall be secured to the container body by latches mounted on

the container body, or by other means specified in the in the applicable specification sheet, and

latch hooks mounted on the cover. The latches and hooks shall be mounted on the cover and

container body as specified in the applicable specification sheets (see 3.1).

3.4.1.3 Vents. The container body shall be provided with vents to permit gases liberated

by the cells of the battery to be purged. These vents shall be located as shown in the applicable

specification sheets (see 3.1).

3.4.1.4 Main power receptacle. The battery shall utilize a two-pin receptacle for a main

power connector. The receptacle shall be mounted as shown in the applicable specification

sheets. The receptacle shall be capable of withstanding a pull out force of 250 � 25 pounds and a

torsional force of 6.0 � 0.5 foot-pounds.