One of the things that I HAVE found to be problematic in this car is that it runs on used batteries.
All of the batteries are of slightly different age and condition, although they are all the same size and chemistry.
When batteries are in series, the worst one limits the rest. When recharging, the worst battery either doesn't get charged all the way, or it does and the others get OVERcharged.
When parked, I can always use a volt meter to measure the batteries individually, but I really need to see what they are doing when the batteries are under load. That means seeing what all the batteries are doing at the same time, WHILE DRIVING.
A while back, I mentioned this to my friend Tom, who is an electronics guy, and showed him photos of an LED bar used for battery monitoring.
Tom has been working on the his version of LED battery monitors. Each board has 4 bars of 10 LEDs, and can monitor four batteries. The LEDs light up from bottom to top as a mini bar graph. The more voltage the battery has, the more LEDs that light up.
Last night, I assembled two boards, a switch, some plexiglass, and the wireharnesses to go to the batteries. The finished device can monitor up to 8 batteries. (I have 6 in my car right now)
Here it is:
I'm going to test out the monitor, see if there are any other features we want to add. In the future we might even sell the battery monitors as kits or pre-assembled.