Lithium batteries for biomedical applications

Lithium batteries have been successfully used in implantable biomedical devices for the last 30 years, and in some cases the use of lithium power sources has significantly contributed to the viability of the device. These battery systems fall into two major categories: Primary, or single-use, cells containing lithium-metal anodes; and secondary, or rechargeable, systems utilizing lithium-ion chemistry. Primary lithium batteries have been used for implantable devices such as cardiac pacemakers, drug pumps, neurostimulators, and cardiac defibrillators. Rechargeable batteries have been used with left ventricular assist devices and total artificial hearts. All of these cells share the characteristics of high safety, reliability, energy density, and predictability of performance. Additionally, state-of-charge indication and low self-discharge are important features, along with charging safety and high cycle life for rechargeable cells.