Powering USB port using lead-acid battery and adapter!

Discussion in 'General Electronics Chat' started by jake9115, Mar 7, 2013.

  1. jake9115

    Thread Starter New Member

    Mar 7, 2013

    So I have a question that I feel is best suited for people who know much about electricity and circuits. I have a 12V 7Ah sealed lead-acid battery (here, FYI http://www.parts-express.com/pe/showdetl.cfm?Partnumber=140-366).

    I also have a small stereo amplifier, 12VDC 2A, that is 15W/channel (2 channels, found here: http://www.parts-express.com/pe/showdetl.cfm?Partnumber=300-385).

    Finally, I have a simple 12V USB adapter, the kind for a car's cigarette lighter (here: http://www.parts-express.com/pe/showdetl.cfm?Partnumber=125-362).

    I know that this circuit board works well with this battery, but I'd like to charge my phone at the same time as I listen to music! Is it possible (and safe), to wire the battery to the stereo amplifier and to the 12V adapter in parallel to power both devices? Are there any problems I should consider?

    Thanks for your comments!
  2. ErnieM

    AAC Fanatic!

    Apr 24, 2011
    Nope, it should all work... for a while at least. A 7AH battery is not very strong and may get drained quickly.

    Also, try to estimate how far it is discharged, especially if it is not rated for "deep discharge." Lead acid prefer a small cycle, not below 50%, for a long life. Drain it completely and it may not ever charge again.
  3. jake9115

    Thread Starter New Member

    Mar 7, 2013
    Thanks so much for your reply... I'm excited about this, and really appreciate your input! I'm going to give it a try.