The KN-13 or HK-13 battery is a 1.25 Volt 14 Ah Nickel Iron Battery, used with the P-323 and P-326 as well as other Russian portable radio sets. Dimensions 80*30*120mm.
The battery is supplied without electrolyte and must be filled before charging. Electrolyte is a solution of Potassium Hydroxide in distilled water with a small amount of Lithium Hydroxide. Electrolyte density 1.2 g/ml. Normal charging rate, 2.3 Amp for 6 hours. Supplied in new and un-issued condition dated 1971, untested.