# 'Wireless' chargers?



## AE35Unit (Oct 18, 2010)

How the heck does this work??
(and why is it tagged under Health and Beauty)

Duracell myGrid Mobile Device Charging Pad: Amazon.co.uk: Health & Beauty


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## chrispenycate (Oct 18, 2010)

If 'twere me (which it isn't) I'd put a coil in the flat bit, a high frequency oscillator in the edge, and a little ferrite coil, rectifier and overcharge logic in the little receiver units that plug in behind your phone. A little wasteful of energy, but we're not trying to make it boil a kettle.

The first use of this type of powering was in surgically installed pacemakers. It might well stay in health for surgically imbedded mobile phones/beepers/locators. Install a GPS in your baby, with remote interrogation, with a one of these under the blanket in his cot; you might never have to wonder where you left the pram again.

More worrying; why did people who had bought it frequently buy Tony Blair's memoirs? Are they rechargeable?


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## AE35Unit (Oct 18, 2010)

chrispenycate said:


> If 'twere me (which it isn't) I'd put a coil in the flat bit, a high frequency oscillator in the edge, and a little ferrite coil, rectifier and overcharge logic in the little receiver units that plug in behind your phone. A little wasteful of energy, but we're not trying to make it boil a kettle.
> 
> The first use of this type of powering was in surgically installed pacemakers. It might well stay in health for surgically imbedded mobile phones/beepers/locators. Install a GPS in your baby, with remote interrogation, with a one of these under the blanket in his cot; you might never have to wonder where you left the pram again.
> 
> More worrying; why did people who had bought it frequently buy Tony Blair's memoirs? Are they rechargeable?


So its like an induction coil! 
As for Tony Bleh's memoirs, lets hope theyre recyclable!


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## Simple Simon (Oct 23, 2010)

Here is a TED video (10 min) about how some MIT guys went about developing this technology. 

Eric Giler demos wireless electricity | Video on TED.com

Considering Tesla back in the day was said to have demonstrated wireless energy this can't really be considered a new technology. We also have the more common form of wireless energy based on harnessing electromagnetic energy in the local environment, solar power. 

What I don't like seeing as Chris above put it is inefficient devices which this most certainly is. In an age of anthropomorphic global warming I think it is a pretty silly idea to be increasing energy uses by 50% (according to the TED video) when we are concurrently pushing to reduce consumption. Most wireless devices are built with low power consumption in mind and can last long periods on battery power. I recently did my thesis on low powered wireless devices which were looking at 3 - 10 year battery life.

On the other hand if this or similar technology can be pushed to 80%+ efficiency it could become a bit more than a gimmick product.


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