Pacemaker batteries mercury zinc

Closely related to the alkaline dry cell is the mercury battery, often used in watches, heart pacemakers, and other devices where a battery of small size is required (Figure 18.10). The anode of the mercury battery is zinc, as in the alkaline dry cell, but the cathode is steel in contact with mercury(II) oxide (HgO) in an alkaline medium of KOH and Zn(OH)2. Zinc is oxidized at the anode, and HgO is reduced at the cathode ... 

Parker B (1978) Obituary a vindication of the zinc-mercury pacemaker battery. Pacing Clin Electrophysiol 1 148-149... 

Figure 23.3 Mallory mercury-zinc pacemaker battery type RM2 (Couitesyof Mallory)...

Mercury-zinc cardiac pacemaker batteries SS t Other types cr mercury battery 33/12... 

From the first pacemaker implant in 1958 by Dr Ake Senning surgeon at the Karolinska Hospital in Stockholm, numerous engineering developments have faced challenges in battery power. In 1972, a primary lithium-iodine battery replacing the mercury-zinc cells greatly extended the cardiac pacemaker life (about 10 years). More details on the history of this battery can be found in ref. 

Other primary cells are also used as batteries for certain applications. In some instances, the battery must be quite small. For a medical device, such as a heart pacemaker, a battery should not only be small, but long lasting. Mercury batteries have come to fill this role. In the mercury battery, shown in Figure 13.14, zinc is the anode as in the alkaline dry cell ... 

Another cell with the same basic construction is the small mercury battery commonly used in watches, pacemakers, and so on. With this battery, the anode is zinc, as in the regular dry cell, but the cathode is steel. MercuryOO oxide (HgO) and some alkaline paste form the electrolyte. You should dispose of this type of battery carefully, to keep the mercury from being released into the environment. 

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