Partnership Delivers Long- and Short-Range RF Charging

Published: August 21, 2023

Powermat offers short range, high power charging of devices wirelessly; while Powercast’s solution leverages UHF RFID for long range, low power charging.

Two wireless charging companies have joined forces to offer a broad portfolio of RF wireless charging options, from high power short range to long-range and low-power systems. Companies such as hospitals can then power everything from medical equipment within a close range or IoT sensors across rooms and through walls.

Pittsburgh, Pa. company Powercast and Powermat (based in Israel), collectively, offer charging devices, modules, and IP licenses so that end users can keep their devices powered without cords and plugs. Both technology companies offer over-the-air charging, but with very different approaches and for different applications. Together, they hope to offer companies a wider set of options.

Powermat offers an inductive and resonance-based wireless solution known as SmartInductive. When the charger and device are within about eight inches of each other, the SmartInductive system transfers a relatively large amount of power (from five to 600 watts). The solution uses magnetic induction. Put simply, an alternating current from a charging device or mat passes through an induction coil. The moving electric charge creates a magnetic field which fluctuates in strength because the electric current’s amplitude varies. This changing magnetic field then creates an alternating electric current in a receiving device’s induction coil, which then converts to a direct current as it passes through a rectifier. The technology can, in this way, transfer energy over the air, bi-directionally. And it transmits both power and data, explains Ygal Sameach, Powermat Technologies’ Business Development VP.

On the other hand, Powercast offers a UHF RFID-based charging solution known as Ubiquity. This can be used for small devices, such as IoT sensors, regardless of whether they have onboard batteries, to provide necessary power at a long range, says Charles Goetz, CEO of Powercast. Ubiquity transmits a UHF RFID signal that the device receives with a built-in receiver from Powercast that captures the RF energy.

Joining Forces

Powermat is a privately owned company established in 2006. The company first introduced wireless charging in 2009 for consumer devices with early deployments at Starbucks and with General Motors. At Starbucks, the company put transmitters in all the Starbucks outlets. “We allowed people to charge their phones while they were in the coffee shops,” Sameach says.

The technology was also used with GM to provide a station for charging phones. “We had it integrated into the car and provided capabilities to charge phones wirelessly.” The company expanded its reach to Samsung and Harman, which were among the companies that integrated charge receivers into their devices.

Original equipment manufacturers (OEMs) now use Powermat’s engineering and IP to make devices that can be charged in more industrial or commercial settings. Powermat designs and develops charging solutions for customers and provides reference designs. “We give them all the production files, including BOLm schematics and layout, and they own the manufacturing, branding strategy, and the marketing,” says Sameach.

Recently, its solutions are being built into micro-mobility devices such as small vehicles and robotics. Traditionally, such devices needed to have batteries recharged, periodically, and that meant a lack of autonomous capabilities or battery swapping. With Powermat technology, there is no need to open a device to remove a battery or plug it in to recharge.

Instead, the solution comes with a built-in receiver, which is embedded on the device. “We license our reference design technology to OEMs,” says Sameach. All platforms can be optimized to companies’ system specifications, he adds.

Companies are using the system to charge light electric vehicles like golf carts, three-wheelers, and bikes in areas such as Asia and India.

Powering Sensors at a Distance and Through Walls

Powercast provides a UHF RFID signal that powers small devices at up to 120 feet away with a power range typically in the hundreds of milliwatts when close and single-digit microwatts at a distance.

Its technology is used to power mobile and computer peripherals, such as mouse pads, but is also deployed for IoT sensor-based solutions. Powercast makes its own products to provide to customers seeking wireless charging at a distance. Some of the devices provided by Powercast consist of wireless power supply without any battery at all – the technology could include smart light switches that turn it on and off like a light bulb on the other side of a wall, based on an RF transmission. Powercast recently released a low-cost RFID reader for relatively lower value products, such as toothbrushes and keyboards, as low as a few dollars. (See RF Device Charges Wirelessly, Acts as RFID Reader

Often customers ask Powercast to also recommend technology that would enable powering of more energy-hungry devices. Healthcare companies, for example, may already use Powercast’s solution for sensors and are seeking a way to wirelessly power other high-energy equipment.

“We have so many customers coming to us who just want to do wireless power,” says Greene, and that includes higher wattage charging. “They ask, ‘can you recharge my robot? Can you recharge my piece of medical equipment that needs 10 watts?’”

Greene approached Powermat to forge a partnership in which they could offer a one stop shop where anybody who wants to do wireless power from single digit microwatts all the way up to 600 watts. For Powermat, says Sameach, “Powercast can really be the productization arm for all of wireless power,” while Powermat offers development, design, and an IP.

Users can either integrate the charging functionality into their device or just buy the module directly from Powercast. In fact, Powercast already manufactures millions of wireless charging devices every year.

With the partnership, Powermat intends to expand its presence in the US. Within the last six months, the two companies have begun talking to customers, many of which are in healthcare, robotics, and smart homes.

In the long term, Greene adds, hybrid devices could result that integrate Powercast’s long-range technology and then can use the closer range high-power transfer to charge things like phones, wearables, and laptops. Such a hybrid approach would consist of two receivers in one device.

Sameach described three main pillars of the wireless charging companies’ partnership. One is to expand the companies’ serviceable market. The second pillar is invention of more devices, and the third pillar is the innovation that can result from the collaboration of engineers and know-how.

Hospitals may be early adopters as they leverage wireless charging to remove cables from mobile or other equipment used in patient care. This reduces safety hazards, the companies point out. In addition, devices that are charged wirelessly would not need an outlet or connection point to a cable, making it possible for them to be fully enclosed and “ruggedized.” That can be especially important for items that need to be sterilized. The systems are also being designed to be scalable over time, says Greene. The companies have discussions underway with new customers, but say they cannot yet reveal the details.

Key Takeaways:

  • Wireless charging companies Powercast and Powermat have teamed up to offer a wider range of charging options for customers in manufacturing and healthcare.
  • The companies are offering charging at up to 600 watts at close range or over a distance up to 200 feet, using UHF RFID in levels measured in milliwatts.