Supercapacitor and Low-Power 3V Battery Team to Power Wireless Sensor Nodes

SYDNEY, AUSTRALIA--(Marketwire - May 11, 2009) - In a technical paper delivered April 27 at the IEEE IT New Generations Conference in Las Vegas, Pierre Mars, vice president of applications engineering for supercapacitor-pioneer CAP-XX Limited (LSE: CPX), presented a supercapacitor-enabled solution for wireless sensor nodes powered by a 3V button battery or other low-power energy source.

Small wireless sensor nodes are now ubiquitous in security systems, fire alarms, asset and people tracking units and condition monitoring systems for industrial, commercial and residential applications. A low-power energy source -- such as a 3V watch battery or a solar, heat or vibration-energy-harvesting module -- can usually supply the average power required by the system, but may not be able to provide the peak power to transmit data over wireless networks such as IEEE 802.15.4 (Zigbee), 802.11 (WLAN) or GSM/GPRS.

For example, supporting even the modest demands of a Zigbee transmission (peak power 10 - 100mA) will shorten a 3V button battery's life, and require a larger battery than would be necessary to support the average load power. Even worse, a 3V battery cannot support a GSM or GPRS transmission (peak power 1 - 2A) at all without some additional source of power.

The CAP-XX BritePower solution resolves these issues with a single-cell, thin-form supercapacitor that stores energy generated at low power by the battery or from the environment, and then delivers it in high power bursts for data collection and transmission. The paper outlines innovative power architectures, showing designers how to use a single-cell CAP-XX supercapacitor rated at 2.7V in conjunction with a 3V energy source, instead of a larger and costlier dual-cell supercapacitor rated at 3V or more. Using a single-cell supercapacitor also reduces the leakage current of the power solution, thereby increasing battery life and reducing energy losses from environmental harvesting modules.

The technical paper is available at http://www.cap-xx.com/news/news.htm#InTheNews, while the presentation can be viewed at http://www.cap-xx.com/resources/pres_wp/pres_wp.htm.

Supercapacitors combine the energy-storage capability of batteries with the rapid charge and discharge characteristics of conventional capacitors. They store electrical energy during periods of low-load power, and then release it in quick "bursts" during peak-power events, supplementing power drawn from the source and smoothing out voltage fluctuations.

About CAP-XX:

Sydney, Australia-based CAP-XX is a world leader in thin, flat supercapacitors for space-constrained electronic devices. Supercapacitors resolve the performance limitations of batteries and other current-limited power supplies and provide backup power if the primary power source fails.

CAP-XX supercapacitors enable manufacturers to make smaller, thinner, longer-running and more feature-rich devices such as camera phones, SSDs, PDAs, wireless sensors and medical devices. The company is listed on the Alternative Investment Market (AIM) in London. For more information, visit http://www.cap-xx.com or email sales@cap-xx.com.

Contact Information: Contact: Michelle Moody Moody & Associates +1-214-363-3460