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Homework Help: How to draw 0.5 amp of current from a 10Ah battery

  1. Dec 9, 2008 #1
    1. The problem statement, all variables and given/known data
    I am planning to use a Li-ion battery running my 4 small pmdc motors rated at 24V and 0.5amps. Is 24V 10Ah battery enough to provide sufficient power to run my application? There is a current controller which is rated at 3amps and voltage upto 44V. I want to restrict the current within the limits of controller which is providing an interface with four motors.

    What is the exact way to draw a required amount of current from a battery rated at 10Ah?

    2. Relevant equations

    3. The attempt at a solution
    I tried two small power tool batteries rated at 18V nearly 1.5Ah, it run my application at first for one or two second, but later on it discharged.
  2. jcsd
  3. Dec 9, 2008 #2


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    Homework Helper

    Sounds like there might be something wrong with those power tool batteries (NiMH?). Anyway, you should be aware that "Ah" has nothing to do with power, but indicates the duration of the fully charged (new) battery. "The exact way to draw a required amount of current from a battery", is to simply connect it to the circuit requiring the power, and make sure that the battery is charged and has sufficient voltage. The circuit that it is connected to should determine the current. If you are concerned about overloading the motors, then you should use a current regulator.
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