Supercapacitors can extend alkaline battery life in portable electronics

摘要

Today's consumers take for granted the ability of the electronics industry to squeeze more functions into smaller, more portable devices. Mobile phones double as cameras and are now adding flash features. Still cameras can increasingly shoot video. And laptop computers can do pretty much anything that can be achieved on the desktop, including driving power-hungry peripherals. This growing array of functions poses a problem, though, for the systems that are used to provide the power: primarily the battery. And, while great strides have been made to cut active and standby power consumption of electronic devices, it is the changing nature of the functions that now presents the greatest challenge. Products such as high data-rate GPRS transmitters and cameras with electronic flash and auto-focus drives require significant instantaneous pulses of power that are difficult to deliver from a battery. At the same time as power requirements have become more exacting, product designers have worked to make it possible to use mainstream battery technology in portable devices. Primarily this means the most common, low-cost form of battery power: the alkaline cell, typified by the familiar AA battery. Alkaline batteries have many advantages: they are readily available at reasonable cost; consumers are familiar with the technology and confident in handling them; they provide high energy density and long life; and they are easy to design-in, long-established and hence well-understood by engineers.