Things have been a bit quiet on the wireless power front, but occasionally I’ll become aware of a new player and will dig in to find out how they work. In particular, given that there are now two main competing resonant (e-field) charging standards, it’s interesting to learn where the various players stand.
As a quick review, the two standards are Qi, at a lower frequency (200 kHz) building off of its existing inductive charging market, and Rezence, at a higher frequency (6.78 MHz), which is a newcomer.
The latest company I ran across was PowerSquare, who announced their technology this past summer. These guys help illustrate how this market is playing out. Some companies, like WiTricity, are firmly allied with a standard (in their case,
Rezence). They develop the basic technology and then license it to companies building actual charging stations. Most of the companies and standards groups I’ve talked with in the past were of this variety.
PowerSquare is not: they’re in the next tier of companies trying to establish a retail brand. As such, their focus isn’t on evangelizing one or another technology; their focus is on selling chargers. So PowerSquare isn’t allied with one or the other approach; they’re going to use what’s available and what works and what’s cost effective.
In this case, their current products leverage the Qi standard. Why? Because that’s what’s there now. In fact, they’re not even doing the newer e-field resonant thing – that’s not ready yet (or wasn’t when they assembled their product). So they use the old inductive (m-field-oriented) approach.
They have, however, adopted some of the techniques we’ve discussed before, creating a pad with an array of coils so that you can put a phone anywhere on it or charge multiple phones at once. So, while they get “x” and “y” positioning flexibility, what they don’t get with that approach is increased “z” spacing: the phone still has to be on the pad, close to the coils. You can’t mount the pad under a table or counter – the resonant approach would be needed for that.
Looking forward, PowerSquare CEO Pavan Pudipeddi sees plusses and minuses for both evolving standards. The biggest thing Qi has going for it is momentum: its legacy helps propel it forward. They already have working technology, albeit inductive, so, even though they’re getting their resonant approach squared away, there’s less pressure because they’ve already got something to sell.
That legacy is also a challenge for Qi, because they’re all about backward-compatibility. So decisions from the past affect the future; that could feel like baggage at some point.
Rezence, on the other hand, has in its favor support from some heavy-hitting companies: Intel, Samsung, and Qualcomm among them. Their challenge is that this technology is new, and there’s intense pressure to get product out the door to establish some traction. In particular, Mr. Pudipeddi wasn’t aware of any uptake of the Rezence technology in phone designs as of when we spoke. (That could have changed by now.)
The first Rezence-based product is expected by the end of the year, however, so the battle will be fully joined at that point. And PowerSquare will continue to use whichever versions of whichever technology hold the most promise for selling units at the retail level.
You can read PowerSquare’s technology announcement here.