Inductive Charging Li-ion Battery

Discussion in 'General Electronics Chat' started by Anabella, Jan 14, 2010.

  1. Anabella

    Thread Starter New Member

    Jan 13, 2010
    Good morning, :)
    I am trying to learn about inductive charging and how feasible it is for a project that I am working on. I need an expert's opinion or any other input that might be helpful.

    Theoretically, this charging method can be implemented in the device, but I need to find out the size of the secondary coil that would be placed inside the device: how big? What about the charging circuitry?

    Three battery scenarios are being considered:
    -Single cell 18650, 1600mAh Li-ion cylindrical battery
    -Two 18500, 1600mAh Li-ion in parallel
    -Two 18500, 1600mAh Li-ion in series

    I understand that this may be a complex question, but any input would be greatly appreciated.

    What information do I need to find out the size of the coil? How do I know if this method (inductive charging) is feasible? How long would it take to charge these batteries? :confused:

    Please help!

    Active Member

    May 15, 2009
    I do not understand the term "inductive charging" Any battery has to be charged with DC or pulsating DC,(typically via a SCR). Maybe you should explain a bit more?
  3. Anabella

    Thread Starter New Member

    Jan 13, 2010
    Inductive charging means that the device being charged does not have any exposed contacts and the charging occurs via electromagnetic field. The device that charges has a primary coil and the device that is being charged has a secondary coil. When they are in close proximity, energy transfers from one to the other and the batteries in the device get charged. In other words, it is a form of wireless energy transfer.
  4. THE_RB

    AAC Fanatic!

    Feb 11, 2008
    I think you will need to build it and test it to get any significant figures.

    As an easy starting point I would go to the discount store and buy one of those $15 rechargeable electric toothbrushes that have a little inductive charger dock on the base. Then see what power you can transfer through that.
  5. mixed_signal

    New Member

    Dec 5, 2009