Wireless Battery Charging Methods for Distributed Soldier Electronic Devices
Navy SBIR FY2008.2

Sol No.: Navy SBIR FY2008.2
Topic No.: N08-108
Topic Title: Wireless Battery Charging Methods for Distributed Soldier Electronic Devices
Proposal No.: N082-108-1030
Firm: Eltron Research & Development, Inc.
4600 Nautilus Court South
Boulder, Colorado 80301-3241
Contact: Michael Pierce
Phone: (303) 530-0263
Web Site: www.eltronresearch.com
Abstract: Today's leading technology for wireless medium power transfer (less than 1kva) from a power transmission station to a load(s) is made possible by means of a magnetically linked resonant power transmission system. This system differs from a magnetically coupled transformer system in that for the magnetically linked resonant system the power transmitter and load(s) are operating at the same center frequency, with a very narrow bandwidth. In the Phase I project, we will demonstrate the ease, reliability and effective range that Eltron's system has. Eltron's system design takes full advantage of system impedance matching using a custom, unidirectional power emitter and spherical receiver antenna to maintain system's frequency and phase lock, producing a power transfer efficiency exceeding 75%. Eltron's system can be modified to accommodate unattended, untethered automatic recharging of a single cell to multi-celled secondary battery power pack used in portable equipment. The equipment containing the secondary batteries can be placed at a varying distance within two to three meters and at any arbitrary rotation relative to the charging system's emitter. Internal to the stated equipment will be a smart battery charger that regulates the batteries' charge, depending on the number of batteries it contains.
Benefits: The anticipated benefits to result from this work include commercial application of this system to all portable battery powered devices. Currently, if a battery powered device needs to be recharged, the device must be plugged into or placed on a custom battery charger, or the batteries must be removed from the device and placed into a battery charger for recharging. If Eltron's wireless battery recharging system were to be used, the device would only need to be in the proximity of (in the same room) the wireless battery recharger for unattended recharging to occur.