Wireless charging of mobile phones

maniish4uis there any instrument made by which charging of cell phones can be done from distant place??i mean to say we switch on device at one place and charging gets done at another place??

No...not till now.

Dont know much about it but I saw a program on Discovery before 3-4 year ago, in which they saw such device . it is very big in size

soni.sapanDont know much about it but I saw a program on Discovery before 3-4 year ago, in which they saw such device . it is very big in size

how it is possible to transfer an electric signal in air medium ???

ok, let me tell you what I have seen.
They were showing a future concept of transmitting energy from sattelite. the procedure is as follows.
1.solar panel on the satellite convert solar energy into electrical energy.
2.Electricity is converted into electromagnectic wave(i think very high frequency).
Then that electromagnetic wave is transmitted on earth where it is received & again converted into electicity.
3.& now suppose elecricity is coming to a lab.
4.In lab again they convert electricity into em wave & at other hand they receive it & convert in elecricity.
5. here they put conventional charger & can charge mobile.

Here at the both end the size of device is very big as they were 1st generation computers.

I read an article on CE forum also in which you can directly charge your mobile.
here the basic principle is the transormers windind principle.
As shown in attached image it is cleared that transormer is basically work wirelessly I mean there is always a gap between primary & 2ndary winding.

now in case of charging wirelessly consider the following point
1. there is only primary winding connected to your switch board with very high number of turns .
2.2ndary winding is now suppose in your mobile.
3.due to very high number of turns in primary, electric flux is spread in whole room & if your mobile is in the range of elecric flux it can be charged wirelessly.
thats all

Nokia Lumia has wireless charger. But its not much. I mean, there is not much range. And some people say it heats up a lot (not confirmed).

Answer to question asked in this thread still remains intact...NO, NOT TILL NOW!

Its not been done yet. However there are several wireless chargers available which needs your device to be placed on a charging pad.
#-Link-Snipped-#

That will shed some light.
Also, MIT did a research on wireless charging over a distance by using two inductor coils and a light bulb. Don't know how far they have progressed.
#-Link-Snipped-#

The biggest problem I think is that when we are transmitting wirelessly, the energy gets spread over a very wide area meaning a lot of energy is wasted. But if that can be controlled like concentrating the signal (in any form) on where and how exactly it falls, there can be better flexibility and efficiency. Low loss since whole of the signal is concentrated at one point. Like a laser beam. Ah, just thoughts! 😁

lalThe biggest problem I think is that when we are transmitting wirelessly, the energy gets spread over a very wide area meaning a lot of energy is wasted. But if that can be controlled like concentrating the signal (in any form) on where and how exactly it falls, there can be better flexibility and efficiency. Low loss since whole of the signal is concentrated at one point. Like a laser beam. Ah, just thoughts! 😁

totally agree, but then your device cant be portable place your device at distant place & dont move it untill chargeged lust like wired charging😕

lalLow loss since whole of the signal is concentrated at one point. Like a laser beam. Ah, just thoughts! 😁

Such a beam will be hazardous. Secondly, any collimated beam requires the source and the sink to be in line of sight.

There's no device with that capability, and if you want to design one, then with the current technologies, it's unpractical. You mean to say, switch on at one side and charge at another side. You can use a remote kind of arrangement and do that.

There a practical device which we all are using in kithen, its your microwave oven.
when you appy electricity I mean you switch on the magnetron tube convert electricity in microwave & now if you pit a metal plate inside where will be a spark that means microwave is converted into electricity.
I just want to say now we can make devices for wireless electricity at current technology

The only problem i see herre is human negligence can become disastrous in your proposal #-Link-Snipped-#

The conversion efficiency of a magnetron is about 70%.
Reconverting it to electricity another 70% (though not by the spark route). Not a happy situation.

Note: Only sharp and thin metal pieces spark. I use round edged open steel vessels in the microwave without problem. No sparks.

Well can't efficiency be increased in the magnetron if we put some super conductors here and there to limit losses to an extent #-Link-Snipped-#

Microwaves can be used to charge Mobile wirelessly.

ConquerorWell can't efficiency be increased in the magnetron if we put some super conductors here and there to limit losses to an extent #-Link-Snipped-#

You do think out of the box. However, as of now superconductors consume huge power to keep them cold enough to super conduct.

bioramaniThe conversion efficiency of a magnetron is about 70%.
Reconverting it to electricity another 70% (though not by the spark route). Not a happy situation.

Note: Only sharp and thin metal pieces spark. I use round edged open steel vessels in the microwave without problem. No sparks.

Sir,I just mean that a practical device is there in our daily usage, so we can improve technology & make some device but I wonder why people need to charge their mobile wirelessly & i think such kind of device may be hazardous for our health

soni.sapanSir,I just mean that a practical device is there in our daily usage, so we can improve technology & make some device but I wonder why people need to charge their mobile wirelessly & i think such kind of device may be hazardous for our health

The 2.5 GHz frequency used in domestic microwaves heats up all water including what is in the human body. That frequency is hazardous. Radio waves are all over the place. They do not seem to bother us much. The best use so far done is a wireless pad on which you place the device and it gets charged. In these the coupling is close and very little energy is radiated away.

bioramaniThe 2.5 GHz frequency used in domestic microwaves heats up all water including what is in the human body. That frequency is hazardous. Radio waves are all over the place. They do not seem to bother us much. The best use so far done is a wireless pad on which you place the device and it gets charged. In these the coupling is close and very little energy is radiated away.

Yes Sir, & I want to ask you if we need to make a a device for wireless charging do we need higher frequency than 2.5GHZ ? & if so, this radio waves are all in all over the room & that can penatrate our body cells& causes serious problem like cancer, is it right?

soni.sapanYes Sir, & I want to ask you if we need to make a a device for wireless charging do we need higher frequency than 2.5GHZ ? & if so, this radio waves are all in all over the room & that can penatrate our body cells& causes serious problem like cancer, is it right?

May be you should look at a more doable and appropriate project out lined by #-Link-Snipped-# here: #-Link-Snipped-#

if the recharging is made wireless ,then power transmission from grid to grid will also be possible
but this can't be done
becoz, the signal must have high amplitude and frequency, if done soo, current could be received only around 0.01amp