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Rate of Charging

  1. Jun 22, 2012 #1
    Dear Experts

    We know that a capacitor is charged such that the voltage increases exponentially and tapers off as it reaches its max voltage.

    I have a lithium ion bettery 4.2V. If my supply voltage is 4.2v, is it not true that :

    1. As the battery is being charged nearer to 4.2v, the potential difference between the input power supply and the battery is lesser and lesser?

    2. This means the flow of electrons is slowed down thus causing the Vmax 4.2v to be reached slower and slower (imagine the capacitor charging curve)?

    3. If say when the battery has reached 3.9v, I increase the supply voltage to 5.5volts, would this potential difference increase help to charge faster? One the battery is fast charged to 4.2, a cutoff mechanism then kick in preventing overcharging?

    Is this a good idea?

    Thanks for reading.

    Best regards
  2. jcsd
  3. Jun 22, 2012 #2


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  4. Jun 24, 2012 #3


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    It would be a terrific idea if you were to use the term 'current is reduced', rather than talking of electrons and their speed. You are unlikely to read those particular terms in any text book dealing with circuits and it really won't help you to use them either.
    No one would argue that electrons aren't involved in the transfer of charge in metals but that's where their relevance ends for simple circuit work. People seem to think it is, somehow, more scientific to talk about electrons in circuits but it's not the way things are discussed normally, with good reason.
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