Pacemaker batteries general

General Electric has now announced the successful development of heart-pacemaker batteries of this type with bromine cathodes, giving an open-circuit voltage of 3.6 V, which are expected to have an operating life of ten years. 

Cardiac pacemakers are generally employed when the cardiac rhythm is either abnormal or too slow. To rectify this problem, doctors prescribe implanted pacemakers that detect the slow heart rate and send impulses to stimulate the muscle using microelectronic circuits. The life of these devices developed before 1973 and incorporating zinc-mercuric-oxide (Zn-HgO) batteries was only between 12 and 18 months. When Li-l2 batteries became available around 1975, the battery life was extended to more than 10 years. The life of devices with batteries developed after 2008 could be more than 15 years. 

Thus far, batteries for general medical applications have been described. Now low-power batteries for specialized medical fields and special medical applications will be described with a particular emphasis on cardiac rhythm management (CRM) systems [7]. Studies performed by medical experts reveal that three distinct types of devices are capable of treating cardiac diseases pacemakers, cardioverter defibrillators, and left-ventricular assist devices [7]. Batteries also have been developed to meet the power requirements of an artificial heart. 

According to heart specialists, four distinct types of medical devices can be used to treat cardiac diseases, namely pacemakers, cardioverters, defibrillators, and left-ventricular assist devices. In addition, the total artificial or mechanical heart needs to be powered by batteries with an emphasis on reliability, safety, and OCV with no electrical surges and voltage fluctuations. Generally, cardiac pacemakers are prescribed by heart specialists when the cardiac rhythm is too slow or when the patient has an abnormal heart beat. This device is implanted in the patient s chest. The implanted pacemaker detects the slow heart rate and sends electrical impulses to stimulate the heart muscle. An electrical signal from the muscle is fed back to the device to make appropriate corrections in the stimulation parameters, which will normalize the heart rate within a hundred microseconds or so. 

Hazardous incidents have been experienced with some lithium systems, particularly those using sulphur dioxide and thionyl chloride cathodes. These incidents generally occur at later stages in battery life under reverse current conditions, during voltage reversal and while operating at high temperatures. Safety incidents have not been experienced with lithium-iodine cells, which is why they power 90% of the cardiac pacemakers presently in use. 

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