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It's Called the Tesla "field of distortion!" ;)
iniewski
I understand Frank...perhaps Tesla or someone knowledgeable in this field could ...
Who holds power in wireless charging?
Peter Clarke
10/30/2012 4:56 PM EDT
SANTA CLARA, Calif. – Wireless charging of mobile devices, simply by laying the device on a suitably wired plate or desktop, seems like an attractive option. Some proponents say 2013 will be a breakthrough year for the technology. Others ask which standard will hold sway and whether convenience will win out over efficiency of energy transfer.
The technology is in place to provide 5-watt chargers that operate at up to 40-mm distance with moves to increase power levels to 15 watts. But efficiency is highly spatially dependent. In addition multiple industry organizations exist and it is not yet clear where the momentum lies.
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Established in 2008 and now with more than 125 members, the Wireless Power Consortium is the largest industry association working towards the standardization of wireless charging technology. However, that does not make the success of the organization, or of its standard, called Qi (pronounced chee) automatic.
For a start some significant players are backing alternative approaches. Qualcomm, Samsung, Broadcom and others are in an alternative consortium, the Alliance for Wireless Power (A4WP) and Intel is still pursuing a proprietary approach.
Qualcomm's alternative position is significant because it held a 48 percent market share of application processors in smartphones in the first half of 2012, according to market researcher Strategy Analytics, providing it with an opportunity to influence decisions by providing reference designs.
Samsung is a member of both A4WP and the Wireless Power Consortium, showing that there is still much to play for.
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Comfortable
10/31/2012 11:37 AM EDT
Apple has already said they have no plans for wireless charging. And their reasoning is sound: one still needs to plug a charger into the wall.
And as far as a universal charging standard: that already exists. It's called USB and is used by everyone in the business.
If wireless charging makes sense, it will be in applications that are similar to a toothbrush - a charging solution that's been around for more than one decade.
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Doug S
10/31/2012 4:51 PM EDT
I have to agree with them. Wireless charging isn't more convenient - it's not like the extra two seconds to plug in your device is a big deal. Having multiple chargers in the locations you need them is cheaper than having multiple charging mats.
A bigger factor is travel. Do you want to carry around a charging mat, along with the power adaptor to plug it into the wall, or just the power adaptor?
Wireless charging is a problem looking for a solution. Perhaps there are certain types of devices where it makes sense (electric toothbrushes as you mention) but for mobile phones and tablets I think it is just a fad popular for bragging rights. Once the "look what my cool new phone can do" factor wears off, few will care about it enough to consider it a "must have" when making purchase decisions.
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Comfortable
10/31/2012 11:44 AM EDT
...forgot to comment why a toothbrush-type application makes sense. This is an application where the charger functionality is hidden. The toothbrush charger is primarily a storage socket to keep your toothbrush off the counter - and oh by the way it also charges. A portable phone doesn't always sit on the charger pad. You have to go out of your way to put your phone where you normally don't store it.
Another bigger application is a floormat electric car battery charger. Again, you park you car on the garage floor - and oh by the way the mat on the floor couples the charge while you are parked.
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Frank Eory
10/31/2012 5:42 PM EDT
You don't always still have to plug a charger into the wall. You guys are missing an obvious one -- a wireless charging mat built into the center console of your car. Sure it "only" eliminates the need to have to plug a phone charger into the cigarette lighter, and deal with the annoying wire that always seems to interfere with the cup holder.
As for the EV charging mat on the garage floor, I saw that demo at CES 2011. It was cool, and the convenience and safety relative to plugging the car into the wall just might be worth the loss in efficiency.
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Doug S
10/31/2012 6:54 PM EDT
Correct me if I'm wrong, but isn't the efficiency loss for wireless charging pretty sizable? That's irrelevant for charging a phone, but for charging a CAR? Not to mention that it is already difficult to deliver sufficient power to a car to charge it in a reasonable amount of time when wired; charging a car wirelessly makes that problem far worse.
I agree with you that wireless charging of a phone in the car is reasonable, but only for that minority for whom phones don't last through the day. I think the best solution to having a phone that needs to be charged during the day is to get a better phone, swap batteries, or get a case with additional battery capacity built in...
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Frank Eory
10/31/2012 7:18 PM EDT
I thought the same thing before I talked to the guys at CES that demo'd this with a Tesla Roadster. They said that with an integrated wireless charging system designed into the car, rather than an add-on like they had at CES, they could get 93% efficiency, and their gap distance between the mat and the secondary winding in the car was 4 inches, which is quite reasonable for that application.
7% loss is indeed significant when you're measuring power in kilowatts, but like I said, it might be worth it for the added convenience & safety.
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iniewski
11/1/2012 1:24 PM EDT
93% efficiency??? since radiation propagates in all directions how do you get such a high number?
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Frank Eory
11/1/2012 2:05 PM EDT
Not my number. I'm just reporting what was claimed.
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iniewski
11/1/2012 2:18 PM EDT
I understand Frank...perhaps Tesla or someone knowledgeable in this field could shed some light here
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MODULATE
11/2/2012 4:30 PM EDT
It's Called the Tesla "field of distortion!" ;)
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