Page 275 - Battery Reference Book

Mercury-zinc cardiac pacemaker batteries 23/5

'--. Depolarizer insulator
Figure 23.2 Mallory mercury-zinc pacemaker battery type 1 (Courtesy of Mallory)

assembly

Figure 23.3 Mallory mercury-zinc pacemaker battery type RM2 (Courtesy of Mallory)

The figures in Table 23.1 are to be considered as 3. Another microporous barrier is clamped over the
minima: One sees immediately that reducing the drain absorbent-separator assembly to close the anodic
does not result in a proportional increase of life. To compartment.
meet the demand for longer service life, Mallory have 4. A secondary barrier has been added to minimize
developed a new cell (RM2 type) (Figure 23.3). Its penetration of zinc dendrites.
construction differs from the earlier one in a number 5. The single can is made of pure nickel.
of respects, as follows: 6. The gasket is moulded around a single biplate top.

1. A collector in the form of a spring ensures a better Its nominal capacity is 1800mAh and a capa-
contact with the anode material and increases its city realization of 93% over 28 months' discharge is
efficiency. claimed. The service life of this battery is likely to be
2. The multi-turn microporous barrier is heat sealed. less than 5 years.