Contactless Electrical Current Transfer?

ferralis (Not an EE) asks: "Recently I've come up with a design for a very fun toy (to be unveiled later if I'm successful). What's missing is a means to send electrical power over a distance of five to ten centimeters (2-4 inches). I've done some research (mostly online) and have found extremely limited information. Even my beloved Google has forsaken me, and even my pleadings to eldritch information deities such as AltaVista have gone unrewarded. Can anyone help?" "The way I see it, to do this a person needs merely set up a high-frequency electrical field using a larger coil (primary) and a similar but smaller coil (secondary) can be placed within it, creating an air-core transformer. Unfortunately I can't find the math or even anecdotes about what happens when the secondary is off-center, or there is more than one secondary introduced... and I am not looking to build a Tesla coil here. I can imagine that many toys could be built using such a system, and one would think the knowledge would be well known and readily available, but apparently it is not. For this application, efficiency is -not- an issue."

Comments

A question

[DAldredge]

Does the person using this toy have to live past the first use? :->

Found this on Google

[hords]

Does this help?

easy

[pizza_milkshake]

use lightning. i've seen it travel much further than you require.

One solution...

[wronskyMan]

You could mix up some chemicals, use your electric power source to put some current into them to cause a complex electrochemical reaction. Call this wireless energy reaction "charging", for example. Then when you want to power your toy, just put the chemicals into a sealed metal container in the toy (such as a "cell"). If you need more power, you could even use a group or "battery" of these "cells" to increase the voltage available to your toy. Then when you need more power, simply remove the chemical containers from the toy, "charge" them again, and put them back in.