Page 320 - Lindens Handbook of Batteries
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13.26 PrImArY BATTErIES
20
15
Weight change, mg 10
5
0
10 15 20 25 30
Limiting current, mA
FiGURE 13.24 Pr48 (size 13) weight gain vs. cell limiting current after 6 days at 20°C,
80% rH.
The maximum power output of the zinc/air battery can be improved by increasing the catalytic
activity of the cathode. Catalytic additives are commonly mixed into the carbon mix component
of the cathode. 38,39 Various forms of mnO are typically used as catalysts for the zinc/air cathode.
x
Figure 13.25 compares the Tafel plots of a carbon cathode with and without a manganese oxide
catalyst. The use of a manganese oxide catalyzed cathode instead of the carbon cathode in a cell will
produce a higher operating voltage.
1.50
With MnO catalyst
x
Without MnO catalyst
x
1.25
E (volts)
1.00
0.75
10 –4 10 –3 10 –2 10 –1 10 0
2
I (amps/cm )
FiGURE 13.25 Voltage as a function of current for an activated carbon cathode with
and without a manganese oxide catalyst.
