Question

3. A typical construction of the most commonly used alkaline battery (AA, AAA etc) is shown as follows: POSITIVE CONNECTION (stainless steel electrode) CURRENT PICK UP ZINC ANODE (2n powder in aqueous KOH paste) ION CONDUCTING SEPARATOR (Porous cellulose or polyethylene film saturated with aqueous KOH) MANGANESE OXIDE CATHODE (MnO+graphite powder in aqueous KOH paste) OUTER CASING PRESSURE EXPANSION SEAL PROTECTIVE CAP NEGATIVE TERMINAL (stainless steel electrode) Anode Zn (s)+20H (aq) -2e ZnO (s)+H2O D, Cathode: 2MnO2 (s+HOMn O (s) +20H (aq),don 0.15V Reduction =-1.28V

Answer 1

D-Open circuit voltage ranges from 1.5 to 1.6 volts. Nominal voltage is 1.5 volts. Operating voltage is dictated by the state-of-discharge and the actual load imposed by the equipment. In GENERAL, the voltage does not remain constant but over the use with the passage of time it decreases and when cell becomes dead for instances, 0.8 volts is considered to be the end-voltage

E-A battery may be discharged under different modes depending on the equipment load. The type of discharge mode selected will have a significant impact on the service life delivered by a battery in a specified
application.
Three typical modes under which a battery may
be discharged are;
1. Constant Resistance (“R”): In this mode, the resistance of the equipment load remains constant throughout the discharge
2. Constant Current (“C”): In this mode, the current drawn by the device remains constant during the discharge
3. Constant Power (“P”): In this mode, the current during the discharge increases as the battery voltage decreases, thus discharging the battery at a constant power level. (Power = Current x Voltage)

the high internal resistance, causes the voltage to collapse. Resistance determines how well electrical current flows through a material or device and is measured in ohms (Ω)