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Wireless Power Recharging Nears Fruition

Posted by timothy on from the lead-codpiece-is-all-that-prevents-it-now dept.

AlexanderT writes "Mobileread.com is reporting that wireless power recharging of mobile devices may become commercially available by the end of this year. Various recently filed patents by Cambridge UK-based Splashpower Ltd. indicate how close the company is in realizing this technology."

26 of 310 comments (clear)

  1. Big Deal by DaNasty · · Score: 5, Informative

    Bah, Tesla did it ages ago.

    --
    Wanna get nasty? - DaNasty
    1. Re:Big Deal by Donny+Smith · · Score: 2, Informative

      Interesting stuff can be found on networks - usually HAARP and Tesla, these two words, produce good results.

      If cell phones are dubious, this shit is scary - it must be impossible to keep out of electromagnetic radiation's reach.

    2. Re:Big Deal by Anonymous Coward · · Score: 2, Informative

      One of tesla's famous experiments was powering an electric motor over a distance of several miles, to a farmhouse nearby his laboratory. The farm had no power generation of any kind (as most other places didn't at the time). Tesla was able to beam power to a receiver, and run the motor to do real work for several hours.

      His notes on this, alas, have been lost.

    3. Re:Big Deal by Soldrinero · · Score: 5, Informative
      Here's a video of a Tesla-style wireless power transmitter in action: wireless power!

      I hope they start using this widely. It will make life a lot more intersting...

      --
      I would rather be killed by a terrorist than enslaved by my government.
    4. Re:Big Deal by dbIII · · Score: 3, Informative
      Forgive me for the newb question, but are there things that he did or use that we to this day still cannot replicate and/or explain?
      No - ever wondered why those concept drawings he did of broadcast powered vehicles stayed as pencil sketches and didn't even get inked in? He moved on to AC transmission via wires. Broadcast power made more sense as a concept back then - power transmission lines didn't exist and everyone knew it would take a vast amount of copper to get electricity to cities which so some inefficiency was acceptable. In the end experiments showed that you had to have a very strong signal to be able to do much at a distance, but someone had to try it out first. A side effect of broadcast power was radio, and Tesla was eventually granted the US patent for that.

      Back then what we take as basic electronmagnetic physics was all weird stuff, the earth return experiments paticularly freaked people out (sticking a light bulb in the dirt and watch it light up), but it didn't take long before we had Telslas three phase alternating current with earth return.

      Edison pushed DC very hard, and played the man instead of the ball by attacking Tesla and not AC and succeeded in discrediting Tesla in the USA - so he's become the subject of mystic crystal crap fake TV documentaries. In the rest of the world he's just the guy who came up with the best system that did a lot of experimentation to find out what would work.

    5. Re:Big Deal by Anonymous Coward · · Score: 2, Informative

      There is not even proof he did it. The most proof I have ever seen is a newspaper article about it. So, no witnesses, and I can't even find direct evidence he admitted to doing such a thing. The whole thing could be a myth.

    6. Re:Big Deal by EnronHaliburton2004 · · Score: 2, Informative

      One of tesla's famous experiments was powering an electric motor over a distance of several miles, to a farmhouse nearby his laboratory.

      WHere's the proof to this claim?

      Any pictures, film, 3rd party verifiable observations, etc?

      We've all seen wireless power transmission over a few feet, which is cool but it couldn't transmit power a few miles unless the machine was huge, and it would probably be hazardous to your health (See the video in one of the other threads here), and we've seen Tesla coils. But where's the proof that he transmitted power wirelessly over several miles?

      Alot of things have been said about Tesla: Inventing small machines which can cause the earth to shake tremendously (like the Tacoma Narrows Bridge), wireless power transmission over a few miles, communication with aliens, or that Tesla was killed by the government and all of his worked is locked away in a secret lab...

      but alot of this is pure rumor, sometimes with a few sketchy notes. Where's the proof?

      --
      94% of Repubs and 21% of Dems voted to renew the Patriot Act
    7. Re:Big Deal by johnrpenner · · Score: 4, Informative


      Tesla did Wireless Power, 'with no diminuation with distance'.

      Tesla's wireless power was technically demonstrated to be feasable.
      But socially unfeasable. Because our Social Structures do not yet permit
      a system where you can afford to give away your power for free.

      The reason nobody wants to use it, is because with Tesla's system,
      you can't METER it - you have to give it away. If you have a Hydro station,
      and use Tesla's 'Magnifying Transmitter' (as he called it), then you would be
      simply GIVING your power away, because you couldn't control who uses it.
      Therefore, all the electric companies used a more limited version of his AC system,
      using wires so that you could put a Power-Meter Barnacle on every site that
      was using the AC power you supplied.

      best regards,
      j

  2. Wireless - really Inductive Coupling by richardoz · · Score: 5, Informative

    When I saw the title about wireless charging, RF (Radio Frequency) came to mind.
    Then I RTFA (Articles / Advertisements) and realized that they are in fact talking about inductive coupling.
    Inductive charging cradles have been used by Sonicare® for several years to charge their cordless toothbrushes.
    It pretty cool anyway!

    --
    All the worlds indeed a .sig, and we are mearly players..
  3. cell phone users by buxton4 · · Score: 1, Informative

    FFP Excellent for people who overuse their cell phones

  4. Nikola Tesla? by LanMan · · Score: 2, Informative

    Didn't Nikola Tesla work on remote power transmission way back when? I thought I remembered seeing info about this in the back of old Popular Science magazines when I was a kid.

    1. Re:Nikola Tesla? by Jozer99 · · Score: 5, Informative

      Yes, but the problem was that if you got close enough to the changing station, it would charge you, in the form of 40000000 kajillion volts. They were also monsterously ineffecient, his test models that could power an acre with usable amerage were the size of light houses. Nowadays, we also know that having that much EMI around constantly will give you cancer in short order. What this company is probably doing is called inductive coupling. This is a relatively simple phenomina. When you have lots of electrity running through a coil, then you place some more wire inside the coil, current is generated in the second coil. This is not a long range effect, so don't think that when you walk in your front door your cell phone and laptop will start charging. It would be more of a "place the device on the special box, no plugging it in" kind of thing. My question is how much power it uses. Induction is much weaker than conduction, so it seems like a laptop that requires 30W of power to recharge would need 1000W to run through the charging mat. I wonder how much more people are willing to pay on their electric bills so they don't have to plug their laptops into the power adapter every day.

    2. Re:Nikola Tesla? by dougmc · · Score: 2, Informative
      Nowadays, we also know that having that much EMI around constantly will give you cancer in short order...

      Riight. And John Kerry is our rightful President.

      To expand on that, we know no such thing. Ionizing radiation (X-rays, gamma rays, etc.) certainly does, but radio and microwaves operate at much lower frequencies and do not cause ionization.

      What the effects of non-ionizing RF raditation on meat (i.e. people) are, beyond heating it up, are not really well known yet. Perhaps it does cause cancer, but it has yet to be proven. Either way, it's not considered smart to expose your self to extremely high RF levels -- and if the levels get high enough, even the thermal effects can become signifigant. People have been known to warm themselves by standing in front of a microwave dish -- but nobody knows what the long term effects of that are. (In the short term, it makes you warm. And looking at it directly can heat your eyes very quickly, sometimes even destroying your eyes if you do it long enough.)

    3. Re:Nikola Tesla? by rco3 · · Score: 4, Informative

      Inductive charging systems are considerably more than 3% efficient. It's nothing but a transformer with no magnetic core and somewhat less coupling than usual. Depending on the physical layout of the charging and receiving coils, energy transfer efficiency can easily be greater than 90%, and the least little tiny bit of intelligence on the part of the charger will have it shut down the charging coil when not needed...

      If systems that used magnetic induction between two coils for energy transfer were so inefficient, we wouldn't use these things called transformers EVERYWHERE. In fact, that was the whole point of Tesla's preference for AC power...

      --

      Ce n'est pas un vrai mouvement de robot!
    4. Re:Nikola Tesla? by Anonymous Coward · · Score: 1, Informative

      Inductive systems can use metal cores (One in the receiving coil, the other in the transmitting coils. However, I have never heard of 90% efficiency. The problem is that the "somewhat less" coupling causes leakage and massive power loss. Case in point, the EV1 inductive charging paddle has ~65% efficiency. http://www.ka9q.net/ev/joke_hybrid.html
      And this is in a situation where they care about efficiency due to the massive amounts of power being transferred. (I couldn't find any more official pages, but this is roughly in the correct ballpark).

      Transformers are specifically engineered and can achieve efficiencies of 98-99%, but they depend on magnetic components that are mechanically bound together with extremely small gaps. The problem with inductive charging is that unless you have a mechanical interface that guarantees sub-millimeter gaps between two chunks of ferrite, the efficiency is going to drop like a brick. Charging cordless toothbrushes is one thing, charging a laptop that has 50x the amout of energy(50Whrs versus 1Whr) gets amusing fast.

  5. Candela rechargeables already do this by JacobKreutzfeld · · Score: 2, Informative

    Cool candle-shaped lights. They recharge when they sit on their base station but it's not a direct electrical contact.

    http://www.thinkgeek.com/gadgets/lights/5cf5/

  6. Oh ok....not so impressive by mcknation · · Score: 4, Informative



    At first I read the summary and freaked.
    Wireless Power!
    My mind raced witht the possible applications...this lasted 1/2 of a second. Then I stopped writing new sci-fi reality in my mind, read the company's website. It's really cool but has no where near the applications of TRUE wireless power.

    /-McK

  7. How is this wireless charging ? by Animaether · · Score: 5, Informative

    How is this wireless charging, if you need to place the object on a specific pad ?

    Sure, there's no actual wire connection to your phone - but it's not like you can just walk around within N feet of some 'emitter' and the phone will charge.
    That specific pad still has to plug in somewhere.
    And that pad is larger than any travel adapter for a mobile phone - so you won't be taking one with you anytime, which means you'd have to rely on one being present wherever you decide to go ? I don't think so.

    And these plates have been around for years. It's called induction charging.

    The only place where I might just see it happening is in airports - but given that most devices will not work with this pad, but will still work with a regular charger, I don't see any airport opting to do away with their regular sockets and getting these plates instead.

  8. Efficiency? by e2ka · · Score: 3, Informative

    Isn't this going to be a horribly innefficient use of power? Instead of directing current directly to the place it needs to be you are blasting unused energy into space.

    If this gets popular, say every cell phone uses one of these, what is the total wasted energy? I bet it's huge.

    1. Re:Efficiency? by Anonymous Coward · · Score: 4, Informative

      Actually, it won't be as high as you think. As it is an inductively coupled system, it relies on magnetic coupling between the charger and the PDA, etc. It is essentially a power transformer where the secondary winding can be removed. If only the primary remains (i.e. there is no device on the charger) the only energy lost will be the magnetizing current of the primary. Granted, this will be a high-frequency power source, so there will be additional losses in the primary side semiconductors, etc., but it's not like this device is powering the whole room.

    2. Re:Efficiency? by h4rm0ny · · Score: 2, Informative


      RTFA.
      Or, barring that, at least read the first few comments.

      No energy is "blasted" anywhere. It's a pad with a zillion tiny connectors that you set your phone on. Pretty stupid, really.

      Actually, there are no connectors - it uses magnetic induction. Bascially, you run current through a coil generating a magnetic field. The device to be charged contains a similar coil and when this is placed next to the first, the magnetic field generates a charge in the device.

      The GP poster you are replying to is actually right in that this is less efficient than just plugging your phone in. True, the phone uses a transformer in the charger, but this is smaller than the proposed pad and more efficient anyway, I would expect.

      --

      Aide-toi, le Ciel t'aidera - Jeanne D'Arc.
  9. TRUE wireless power... by Manchot · · Score: 2, Informative

    "True" wireless power is not all it's cracked up to be. To do it, you'd either have to a) spew power all over the place, a la Tesla, or b) use a focused beam and send it directly at the device. The first option is a tremendous waste of energy, and the second would probably be unreliable (as well as cancer-causing).

  10. The trick is ... by Anonymous Coward · · Score: 2, Informative

    If you drive the primary coil with a very spiky signal, you get max. dv/dt. That means effectively that you don't need a core. You can couple a decent amount of power at a range of a half inch or so. Look at the charging circuit on your toothbrush. You will most likely find something like a 555 timer. (I had a couple of students implement this as part of a project about seven years ago.)

    Another example of such power transfer is rfid chips. In that case, the transfer takes place over a range of feet. The bottom line is that the technology isn't very radical.

    On the other hand, the idea of some kind of standard interface for charging batteries is huge. As I sit here, I see approx. a zillion battery chargers. They infest my bookshelf. Everything I own has a different battery charger. Being able to set three cell phones, PDAs and digital camera on a pad to charge is a very welcome idea. It would sure clean up the mess of wires and wall warts that I see before me.

  11. Re:Wireless - really Inductive Coupling by shokk · · Score: 2, Informative

    Mine has been working fine for years. Not only do I use it, but my wife and two of our three kids use it. My third child is only 1-1/2 YO so he's still getting the hang of the non-electric version, but that Braun will work just fine for him. Our original brush cost US$50, and I've seen them in the store for US$20 that now have a two-minute timer. You probably throw away $20 on a weekly basis, so what is $20 annually even if you were to somehow mess up the new one in a year's time?

    --
    "Beware of he who would deny you access to information, for in his heart, he dreams himself your master."
  12. Re:But its different this time.. by jedi-monkey · · Score: 2, Informative
    ...this time its Patented!

    Well, not exactly...

    All these patents:

    645,576 , 649,621 , 613,809 , 685,955 , 685,953 , 985,954 , 787,412 , 723,188 , 725,605

    and most notably,

    1,119,732

    Are all Tesla's patents regarding such a feat.

  13. Re:Wireless - really Inductive Coupling by pclminion · · Score: 2, Informative
    There wasn't even a LOT of wire, so it probably didn't provide too much current.

    Actually, you've got it backwards. Coils with fewer turns can supply more current than coils with more turns, but at a lower voltage. More turns == more voltage, less current. Fewer turns == lower voltage, higher current.

    For the purpose of charging a battery, the only concern is voltage. You have to have at least battery voltage in order to get current to flow into the battery. So ideally, you want to use as few turns as necessary to achieve the desired voltage (over-volting the battery is pointless and destructive).