At least five different approaches to wireless charging have emerged to date, each backed by multiple companies with different implementations. The technology captured broad interest at the Consumer Electronics Show in January where Palm previewed its Pre phone using an optional wireless charging pad called the Touchstone.

Palm has since released the device becoming the first major cellphone maker to ship such a product. Teardowns of the design have so far been inconclusive about the origins of the Touchstone's technology.

The CEA effort has attracted a broad range of companies including Qualcomm and WiPower (Altamonte Springs, Fla.) that have their own loosely-coupled magnetic inductive technology as well as Fulton Innovations LLC (Ada, Mich.) and National Semiconductor which have closely-coupled induction technology. Startup Powermat (Neve Ilan, Israel) which uses a proprietary technology has also been part of the CEA group.

"All relevant technologies will be reviewed," said John Suh, a member of an advanced technology group at General Motors chairing the CEA effort. "By understanding the customer segments, the user scenarios and pain points, I hope the task force will be able to describe the net utility of wireless charging," he added.

Other potential users of wireless charging technology in the CEA group include Microsoft, Panasonic, Pioneer and Philips. Audiovox and Energizer are also part of the group. It is expected to conduct its first formal meeting as a telephone conference on July 29.

The CEA move comes just weeks before the Wireless Power Consortium (WPC) expects to make an announcement about the status of its standard. The group--which includes Fulton, National, Philips, Samsung, Texas Instruments and others--is expected to release before the end of the year an ad hoc standard for tightly-coupled inductive technology geared for 5W devices.

"We will be making an announcement in a couple of weeks," said Menno Treffers, a senior director of standardization at Philips and a member of the WPC. "It will be a statement about where we stand in the [standards] process," he said.

Fulton and another WPC member, ConvenientPower Ltd. (Hong Kong), have different implementations of the technology for which the WPC aims to define a single standard. Other companies have also been making technical contributions to the WPC effort.

"The mood is constructive, and there's really good work going on," said Jim Schuessler, senior technical marketing manager for portable products at National.