all about battery supply

Discussion in 'Homework Help' started by rakesh696, Jan 2, 2009.

  1. rakesh696

    Thread Starter Member

    Dec 15, 2008
    friends .,
    i need a circuit of battery cherger for a 12 v 10ah battery from a 230V ac supply and the circuit should have
    1) it should stop charging if it exceeds full charging
    2) and charging can b VARIED froM 13.5v to 15v approx
    3) and current raring output is above 4A
    4) automatically turns ON charging circuit if voltage of batttery reduces
    5)indicates over charging current
    6) If the circuit is powered off, the battery should be disconnected from it's output

    plzzzzzzzzz help ...i am forced to this project by my sir .....
  2. italo

    New Member

    Nov 20, 2005
    TRY an lm117 with a bypass transistor. For a 12v battery like for your car 13.68v is a good voltage to keep steady I don't think you like to change that. BY adding a 0.3 ohms in series with the output you can limit the max current to 4 amps. Increasing the voltage will not be practical since the battery will hold to 13.68v if connected until it gets hot and battery replacement is in order.
  3. rakesh696

    Thread Starter Member

    Dec 15, 2008
    tnk u bro.............
    can any 1 provide clear circuit diaram dat satisfies the constraints mentioned above
  4. SgtWookie


    Jul 17, 2007
    Since this is a homework assignment, it should have been posted in the Homework Help forum.

    We can't do your homework for you. However, if you run into problems or need reviews of your schematics, we can help you there.

    The type of battery to be charged is very important. Lead-acid, sealed lead-acid and AGM (absorbent glass mat) have different charging requirements from gel-cell.

    If your battery is a gel-cell, attempting to charge it at a 4A rate will very likely damage it. The "rule of thumb" for charging gel cell batteries is 1/8 of their AH rating; in your case 1.25A.

    I suggest that your starting point is to get the battery part/model number and manufacturer, and find the maintenance, care and charging instructions on the manufacturer's website. If you can't find the manufacturer's site, find a cross reference for the battery model and use another manufacturer's instructions.
  5. hgmjr


    Jan 28, 2005
    As sgtwookie pointed out, this thread appears to belong in the homework forum. I have taken the liberty of relocating it.

  6. rakesh696

    Thread Starter Member

    Dec 15, 2008
    battery.........12v 10Ah