I'm new here, so if this post is in the wrong part of the forum, please feel free to move it. I wasn't exactly sure of where to put it.
I use a power wheelchair for most of my mobility. Like a car, because I spend so much time in it, I want to make it more functional. I would like to figure out a way to tap its 2 12V batteries for 12V so that I can power the following items:
A) An automotive cigarette lighter/power port, to connect things like a USB charger for my cell phone. (Standard USB, 5V @ 500ma)
B) Future idea - A netbook. (30 watts?)
C) Future idea - LED lighting. (Forward illumination/rear markers)
D) A LOUD horn!
I am not very well versed in electrical theory, but from what I know, tapping only one of the batteries will result in it being drained faster than the other and will lead to killing the battery, stranding me without motive power, or possibly damaging the charger.
I would ideally like to have the system set up so that I can charge the batteries normally, by plugging in my standard 8A (Soneil) charger, and without having to add a third battery which I would have to charge separately. This would have the additional advantage of being able to monitor the charge level through the standard joystick display.
Fresh batteries will be installed on 4/15. I will take photos of the wiring setup and measure the available working space in the battery compartment, if needed.
Preferably, all the required electronics would fit in the battery compartment, to optimize space savings and protect them from weather.
How can I do all of this? About how much money would it cost, ballpark, assuming that I had someone do the work for me? (I can't get in a position to work on the chair comfortably)
Any comments/suggestions would be appreciated - Thanks!