battery monitoring

I should have individual battery monitoring

this looks okay but a but bulky. I would like a 1 wire protocol or something similar

http://www.evconvert.com/article/led-bargraph-battery-monitor


from one of the comments on that page

Another option I’ve been mulling over is an Arduino-based battery monitor. I’m not really a hardware guy, and barely a programmer, but from what I’ve read of this open source platform, it shouldn’t be horribly difficult to build a 6-battery monitor (the board has 6 analog inputs) that can send live data to a laptop: arduino.cc

I may just look into this as a winter project. The pre-assembled board is about $30 US.

or another comment from that article

If your in Astralia DSE have a this in kit form for about AU$9 each.

http://www.dse.com.au/cgi-bin/dse.storefront/482e8bd1040477a8273fc0a87f9c06f3/Product/View/K4611

or check out the PakTrakr - whatever that is
http://www.paktrakr.com/Shopping.html

or a circuit based on the MAX8211
http://www.maxim-ic.com/quick_view2.cfm/qv_pk/1273


or how about this?
http://www.futurlec.com/CarBatteryMonitor.shtml


or this
http://www.electronics-lab.com/projects/automotive/009/index.html

or this
http://www.uoguelph.ca/~antoon/circ/batmon12.htm