The E-E Battery Computer Project. Part I
Saturday, February 10th, 2007
It’s been a while between posts because I’ve rewritten this one several times, just can’t seem to find the balance to keep it interesting for the technophiles and those a bit more perplexed by elec-trick-imy. So apologies if this doesn’t hold your interest…
The Issues
- My lead acid AGM batteries will be damaged if overcharged.
- I want to collect data about my batteries, while driving and while charging.
- I want everybody to see my data, live on the web - if possible!
The solution
A computer that;
- monitors all the individual battery voltages (12 x 12Volts).
- monitors the battery pack current.
- shuts off the battery charger if any battery is over the recommended maximum voltage (14.7V).
- applies a temporary load to any battery that appears to be charging quicker than the rest.
- stores the collected data onto a removable memory card.
- streams the live data to a standard serial port.
- is very configurable.
The progress
So far my friend and brother-in-law, Mark Philips has done a fantastic job of putting together a little AVR micro controller board that does all the logic stuff required for the above.
His micro (well, it’s mine now!);
- has an SPI interface that talks to my 16 channel A/D MUX for individual battery monitoring.
- has a basic 80 char two line display.
- sends the data collected from the MUX out on a RS-232 Com port.
- saves the data collected from the MUX onto a SD memory card in CSV format.
- has an ISP port for simple reprogramming of the micro.
- has its own real-time clock.
- has another 13 programmable pins to do lots more I/O stuff with!
