Medical Device Link.

Originally Published EMDM March/April 2002

PRODUCT UPDATE

Ultralife Batteries (UK) Ltd.

Return to Article: Electronics Open New Avenues in Device Design

Great strides have been made increasing the energy density of lithium-ion batteries, which has doubled in the last 10 years, while lightweight polymer batteries that can be produced in an array of sizes and shapes have created new opportunities for device designers. Ultralife Batteries (UK) Ltd. (Abingdon, Oxon, UK) supplies several types of lithium batteries as well as polymer rechargeable batteries that are suited for use in a range of devices.

Cylindrical and pouch cell lithium batteries provide very high discharge rates, even in extreme temperatures. Because they exhibit no voltage delay after long storage periods and have a shelf life of up to 10 years, HiRate batteries are routinely used in automatic external defibrillators.

Lightweight wafer-thin batteries that combine high energy density, long life, and a wide operating temperature range open up new design possibilities for medical product engineers. Thin Cell batteries can be as thin as 2 mm, thereby enabling a reduction in the size and weight of the medical devices that they power. One emerging technology benefiting from these power sources, according to the firm, is radio-frequency identification tags that enable the wireless tracking of medical records.

Polymer rechargeable batteries combine high energy chemistry with state-of-the-art polymer technology to produce a cell that can be configured in almost any prismatic shape and thickness. "Technically, there are no limits in terms of shape," says Julius Cirin, vice president of product and industry marketing at the company's US headquarters. "Practically speaking, we stick to prismatic shapes, which generally refers to squares or rectangles. We can produce round, oval, or triangular polymer cells," he adds, "but that would be inefficient from a manufacturing standpoint." Thicknesses range from approximately 1 to 5 mm.

These batteries afford medical device designers the ability to develop smaller, lighter, more-powerful products without having to conform to a fixed battery shape or size. "We have worked with prosthetic devices for children, for example," says Cirin, "providing a powerful battery that can fit into the wrist area. We have also been involved with hearing-enhancement applications, where a fairly thin and lightweight form factor is required."

Copyright ©2002 European Medical Device Manufacturer