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Charging a 9v battery

  1. Jul 28, 2013 #1
    I have a very small project which requires a typical 9v battery for mobile use. But to keep from having to replace the battery I would like to put in a rechargable 9v battery and use a 9v output from a dc power plug to charge it. I have charged batteries with solar panels before and all that is needed is the diode on posotive. But is this the same for what I am wanting? Will the battery not have enough resistance to keep a safe low amperage? or will the battery consume only what it needs? or must a resistor be put in series with the diode?
  2. jcsd
  3. Jul 29, 2013 #2


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    it depends on the type of battery to what the charging requirements are
    for example LiPo's require very specific charging circuits. Others require specific voltages and or currents

    Pretty much all of them need some sort of circuitry to make sure that the battery isn't overcharged
    causing it to bulge, explode, catch on fire etc

    so determine what type of battery you are going to use, then do some google searching on charger circuits relevant to that style of battery.
    If you find an appropriate charger circuit, then post a link to it on here and let the guys here check it out to make sure its fit for the job :)

  4. Jul 29, 2013 #3
  5. Jul 29, 2013 #4
    Well for one, that circuit design makes use of 230V AC. Do you have access 230V mains or, for that matter, an appropriate step-down transformer?
  6. Jul 29, 2013 #5
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