back to article iPhone case uses phone's OWN SIGNAL to charge it (forever, presumably)

A new Apple iPhone 6 case harvests energy from the smartphone's radio transmissions and use it to charge the battery, its developers claim. Nikola Labs, which touted the product at TechCrunch Disrupt on Monday - and which was selected to pitch to the crowd there "after being selected by the techCrunch editorial team and and …


  1. RosslynDad
    Thumb Up


    This helps reverse that worrying decline in articles that don't use the word "asymptotic". Well done Ed. More please.

  2. Anonymous Coward
    Anonymous Coward

    Forgetting for a moment that it couldn't possibly run off its own signal without reducing the range, lets assume it works by harvesting 'ambient' electricity. In that case it would be theft of utility from the transmitter not to mention a real pita to anyone trying to get a signal.

    1. Cliff

      It harvests energy proportional to the inverse of neural activity. Probably be sold on the woowoo shelf of health food stores that also sell stickers to block 'unhealthy' radiation from mobile phones using the power of tachyons and some pretty holograms. And woowoo.

    2. Nicocys

      "not to mention a real pita to anyone trying to get a signal"

      You're not holding it right.

  3. Aristotles slow and dimwitted horse Silver badge

    *cough* *cough* ahem!!!

    "Vulture Central is quite sure that our readers will really get behind this device and not pooh-pooh the mobe-charging claims one bit. Right?"

    Yeah, because we'd never do that...

    1. Code For Broke

      Re: *cough* *cough* ahem!!!

      I don't get the point of this post.

  4. cirby


    So... they're lowering output signal strength to make the battery last a little longer? So the phone will automatically use even more power most of the time to try and talk to the nearest tower?

    Do tell.

    1. Dave 126 Silver badge

      Re: Physics


      Why would Apple make a phone that used more energy than necessary to power its radios when battery life is a competitive selling point?

      It would more sense for the phone to disable its own WiFi, Bluetooth and 4G when they are not being actively used - like the Stamina Mode on some Sony phones.

      Given the size of this proposed case, you might as well get a cheaper 'battery case' and increase your phone's battery life 50% +.

      1. Ralph B

        Re: Physics

        To be most efficient, I think this case should also include a screen-facing solar panel. That way, any of the light emitted by the display can be recaptured for charging the battery.

        Since all wasteful* function-related EM emissions - visible and invisible - will now have been prevented, the phone will now serve no useful purpose when inserted into the case, and so can be switched off.

        If this is done, I predict that battery life could then be extended to be whatever it is when the phone is switched off.

        * Since the idiot buyer of this case will only have been using the phone for yabbering to similar idiot friends, or using social media, casual gaming or dating apps, then ANY functional use of the phone can been classed as wasteful. Better to switch it off, if making it explode is not a technically or morally acceptable option.

  5. Schultz
    Thumb Up

    Just don't forget ...

    to take off the case when you want to use Wi-Fi, Bluetooth, or LTE.

    Otherwise, it sounds like a perfectly reasonable idea. Maybe the phone could also feed some power back into the grid via wireless charger during times of peak demand -- harness your phone battery for the smart grid!

  6. streaky Silver badge



    The phone's entire radio usage probably doesn't use 30% of its battery life, if you pile on inefficiencies and losses, I can't imagine how you get to 30% eating all the energy from radio emissions - and you need some of that energy to get out regardless, else your phone won't communicate with anything.

    To get to 30% you have to be claiming you're getting energy from nothing, surely?

    Edit - just been reading engadget's article that fawns all over this thing:

    The harvesting antenna and DC power-converting rectifier circuit

    It's those bomb detectors in Iraq all over again.

    Dr. Lee's reputation as the former chair of Ohio State's Electrical and Computer Engineering gives this seemingly kooky outfit some much-needed credibility

    What reputation exactly. I see no credibility anywhere.

    1. Eddy Ito Silver badge

      Re: Uhhmmmm..

      Oh come on, you're not giving it a chance. I'll bet they thought of the fact that they would need to recover more power than the radio uses so they likely also have a photovoltaic panel sitting over the display to capture the wasted photons to convert to electricity as well. I'm sure it's all been well thought out.

  7. Snivelling Wretch

    What's missing?

    I think we need Stephen Fry to explain it, that's what.

  8. simmondp

    ... the company will shortly be releasing a companion perpetual motion machine....

    1. Anonymous Coward
      Anonymous Coward

      ...and the perfect encryption scheme: any arbitrarily sized block of data encrypted as a single bit.

      1. Radelix

        Don't forget about the Law Enforcement mandated easy decryption

      2. Anonymous Coward
        Anonymous Coward

        > ...and the perfect encryption scheme: any arbitrarily sized block of data encrypted as a single bit.

        Well, that's possible today. All you have to do is encrypt first and then compress¹ using a sufficiently lossy algorithm. If it's lossy enough to really live up to its name, it should be capable of giving you one-bit cyphertext, which should also be quite resilient to any form of plaintext recovery attack not involving crystal balls².

        What's this company's website again? I'd like to apply as their Chief Information Security Officer.

        ¹ The opposite as conventional norm when using non-lossy algorithms.

        ² Or rubber hoses.

        1. Michael Wojcik Silver badge

          > ...and the perfect encryption scheme: any arbitrarily sized block of data encrypted as a single bit.

          Well, that's possible today. All you have to do is encrypt first and then compress¹ using a sufficiently lossy algorithm.

          It's always been possible, and can be done with lossless compression.

          What's difficult is encoding three arbitrary messages with a single bit.

      3. Red Bren

        I have created such an encryption scheme, but the decryption key is exactly the same size as the original file...

    2. Anonymous Coward
      Anonymous Coward

      ... and don't forget this is aimed at Apple users.

  9. The last doughnut
    Thumb Up

    At last! Endless chat and kitteh pix.

  10. msknight Silver badge

    Doesn't surprise me

    When I'm recording video at home using a lapel mic, I've got to turn the iPhone to airport mode because it blats all over the audio track even when it's on the other side of the room. The other phones I have don't do that. *sigh* - I don't know whether to class that as a success or a fail.

    1. Dan Paul

      Re: Doesn't surprise me

      FCC Part 15 regulations state that equipment is not allowed to step all over the frequencies of other equipment.

      That's a big Apple FAIL if it "blats" all over the audio track you are recording.

      1. Bob Dole (tm)

        Re: Doesn't surprise me

        >> That's a big Apple FAIL if it "blats" all over the audio track you are recording.

        I've experienced this issue with every iPhone I've owned - 5 of them across different generations. I've also experienced it with quite a few other non-Apple devices.

        Sure, the regulations state what they are or are not allowed to do but from what I can tell regulations are meaningless until a company gets hit with a lawsuit. Then they pay a small "settlement" fee and quietly change their product. It's not like the government actually *tests* every single device that hits the market.

        1. Andrew Meredith

          Re: Doesn't surprise me

          @ bob dole "It's not like the government actually *tests* every single device that hits the market"

          Actually they do. The US requires FCC EM testing and there is a comparable CE EM standard.

          1. Anna Logg

            Re: Doesn't surprise me

            CE does not require testing, manufacturers can self certify based on their own judgment call on whether testing is necessary or not; although they still need to present information relevant to the product to a Notified Body.

      2. Nick Stallman

        Re: Doesn't surprise me

        Unless the wireless mic is using frequencies it isn't supposed to be, then too bad.

        1. msknight Silver badge

          Re: Doesn't surprise me

          It's cabled :-)

          Similar to this -

        2. Anna Logg

          Re: Doesn't surprise me

          Pretty much all cellular radio technologies vary the amplitude of the radio signal itself at a frequency within the audio range, so there is a finite possibility that audio equipment (particularly equipment with high gain and relatively poor screening) will be sensitive to this modulation and produce an audio output from it. Particularly so with GSM IMX.

          1. werdsmith Silver badge

            Re: Doesn't surprise me

            In order to be sold in USA, it must pass its FCC testing and get its little FCC logo and details on the back.

          2. Code For Broke

            Re: Doesn't surprise me

            Now that's the kind of comment I come hoping to read. Thank you.

  11. Jamie Jones Silver badge

    Ah.... Reminds me of this

    Not my work, courtesy of a b3ta user:

  12. Ben Liddicott


    Just... morons. Like the "smart road" which harnessed the motion of vehicles to generate electricity...

    1. Cynic_999 Silver badge

      Re: Morons.


      Just... morons. Like the "smart road" which harnessed the motion of vehicles to generate electricity...


      While I cannot see the above idea as being practical or cost effective, it does have the advantage that each device on a busy road would get quite a bit of energy from thousands of heavy vehicles running over it per day so is at least feasible. In contrast, the total amount of EM energy impacting on the small area of a phone case would be down in the microwatt region except from the phone it is covering, which would be a few mWh at best over an average day - way below any level that would make any significant difference to the battery's charge state.

      1. Ben Liddicott

        Re: Morons.

        No, because the energy captured by the road results in a higher effective rolling resistance to the car. It's just a disguised petrol generator.

    2. MrXavia

      Re: Morons.

      Actually the smart road has some merit, your only capturing existing vibrations and converting to electricity, the vibrations themselves have no purpose...

      Although a better idea is to have roads made from some form of solar/thermal energy capture, since they are exposed to sunlight for much of the time...

      The iPhone signal harvesting is like driving a car on a treadmill..

  13. gloucester

    30% of 30% is?

    @Ed: Surely that 30% recoup could only be re-applied to itself, not the whole initial 100% charge, so 30% of 30% is 9%, 30% of a further 9% is 2.7%, etc. The total tending to c. 142.857% (i.e. 42 odd % increase in charge time).

    I suspect though the harvesting isn't that efficient, so the 30% quoted is the overall increase, so efficiency of 23 odd percent. Still high but perpetual motion (or kittehz) it isn't.

    1. Bob Dole (tm)

      Re: 30% of 30% is?

      You're really thinking about this too hard.

      They picked a number out of the air... Something not too small so people are interested but not too big so that they can't come up with 1000 reasons why *you're* particular phone isn't getting the 30%. It's called "marketing speak".

    2. Michael Wojcik Silver badge

      Re: 30% of 30% is?

      Isn't it basically continuous compounding, with an additional term representing the amount consumed over time? Looks like ~135% total unicorn-battery-life to me.

      Of course the whole thing is nonsense.

  14. Chas


    2nd Law of Thermodymanics anyone?


    1. MyffyW Silver badge
      Black Helicopters

      Re: Err...

      @Chas well said that man.

      Now consider the combination of the 2nd Law of Thermodynamics, plus use of the word "Asymptotic", and throw in a kooky outfit called "Nikola" and this is starting to sound like my kind of summer reading....but not my kind of consumer electronics.

      1. Anonymous Coward
        Anonymous Coward

        Re: Err...

        Err... is that spelt 'snake oil'?

    2. Roj Blake Silver badge

      Re: Err...

      As Homer Simpson once said, "Lisa, in this house we obey the laws of thermodynamics"

  15. This post has been deleted by its author

    1. Cynic_999 Silver badge


      It's certainly possible to pick up a useful quantity of energy from ambient electromagnetic waves - an old band I VHF antenna connected to a capacitor via rectifying diodes will give you enough charge to light an LED after a while, and you could probably power a small CMOS circuit from it.


      No, not enough energy to be all that useful unless you are extremely close to a high power transmitter. An exceptionally strong signal into a full-size aerial would give you 100mV at the aerial socket, which assuming a 75 ohm load impedance would amount to 100uW of power.

      1. Anonymous Coward
        Anonymous Coward

        Voltage from EM waves

        I remember a school demonstration using a klystron that could light a very small incandescent bulb connected to a tuned dipole, but that of course does not need rectification. Silicon diodes need several hundred millivolts to overcome the junction potential, germanium diodes just behave like capacitors.

        I did once manage to produce a rectified DC large enough to deflect an AVO to 5V - using a 5kW cavity magnetron a few metres away, and a microwave diode. It was pointed at the outside corner of a building on the 1st floor, but with hindsight I wouldn't recommend this experiment.

        Based on this and a few other RF experiments over the years I have come to a conclusion about the feasibility of this product, and concluded that it simply isn't expensive enough. Like directional OFHC speaker cables and multi-screened low capacitance coax that improves stereo separation on digital signals, if it doesn't cost over $1000 it can't possibly work.

        1. Anonymous Coward
          Anonymous Coward

          Re: Voltage from EM waves

          We used to light a small neon bulb by putting it close to the output stage on an HF transmitter. If the colour was purple it was supposed to indicate parasitic oscillations. In which case you fitted a parasitic stopper to the anode circuit - unless there was one already fitted in which case you removed it.

          1. werdsmith Silver badge

            Re: Voltage from EM waves

            That's too much hard work.

            I use a field strength meter.

  16. Vladimir Plouzhnikov

    What's new about it?

    That was described in a fair bit of detail by Robert Heinlein in Waldo, ages ago...

    What next - Magic, Inc.?

    Looking at these people - so smug, as if they've built the Gay Deceiver...

    OK, I know, that's enough already... :-)

  17. Slap

    I'm calling bollocks here

    I'm calling bollocks here, however I do maintain an open mind and would like to see independent testing regards to signal degradation in combination with the amount of power harvested. 30% is a wild claim and without that testing this remains in the same category as magic balls, cable lifters and $2000 interconnects in the audiofool world - bullshit and snake oil.


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