Performance zinc/mercuric oxide batteries

Cadmium/Mercuric Oxide Battery. The substitution of cadmium for the zinc anode (the cadmium/mercuric oxide cell) results in a lower-voltage but very stable system, with a shelf life of up to 10 years as well as performance at high and low temperatures. Because of the lower voltage, the watthour capacity of this battery is about 60% of the zinc/mercuric oxide battery capacity. Again, because of the hazardous characteristics of mercury and cadmium, the use of this battery is limited. 

PERFORMANCE CHARACTERISTICS OF ZINC/MERCURIC OXIDE BATTERIES... 

The zinc/mercuric oxide battery is best suited for use at normal and elevated temperatures from 15 to 45°C. Discharging batteries at temperatures up to 70°C is also possible if the discharge period is relatively short. The zinc/mercuric oxide battery generally does not perform well at low temperatures. Below 0°C, discharge efficiency is poor unless the current drain is low. Figure 11.9 shows the effect of temperature on the performance of two types of zinc/mercuric oxide batteries at nominal discharge drains. 

The performance of the zinc/mercuric oxide cell at various temperatures and loads is summarized in Figs. 11.12 and 11.13 on a weight and volume basis. These data, based on the performance of a 800 mAh battery with a dispersed anode, can be used to approximate the performance of a zinc/mercuric oxide battery. 

The performance advantages of several types of lithium batteries compared with conventional primary and secondary batteries, are shown in Secs. 6.4 and 7.3. The advantage of the lithium cell is shown graphically in Figs. 7.2 to 7.9, which compare the performance of the various primary cells. Only the zinc/air, zinc/mercuric oxide, and zinc/silver oxide cells, which are noted for their high energy density, approach the capability of the lithium systems at 20°C. The zinc/air cell, however, is very sensitive to atmospheric conditions the others do not compare as favorably on a specific energy basis nor at lower temperatures. 

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