Thanks Guys
But I've placed it on the back burner for now. There was this company that is trying to sell us this super charger that helps recover batteries so we all ready have that special charger that creates those pulses to breakdown the lead sulphate crystals. The idea was that we load test the batteries first that had been in service sometime see how good they where then place them on this charger and re-test them to see if the runtime goes longer, I already have designed a 30amp load tester which recorded the runtime, This was based on 4 90W free standing resistors and 2 mosfets for each pair of resistors using PWM seems to work quite well but the draw back is there all common grounded but applies the 30amp load individually to each battery, This other company said they could design a newer all singing all dancing but they used 4 power transistors and 4 50W power resistors mounted on a larger heatsink like I posted above, but the trouble was it kept over heating and blowing up where mine did not overheat you could always touch and hold the heatsink. The only difference was I used PWM to control the load and they used DAC'S in linear mode. They also tried to add reverse polarity protection so no matter which way you connected the battery it still ran the test, But this had a major flaw and draw back once you connected the batteries and turned the unit on before you started the test and realised you had one battery wrong and tried to connect it the other way without turning the unit off it would go bang and blow the power transistors up. I know it did not matter really as you could just start the test and it would work but to me this was a design fault of there unit.
So I wanted to design another mark 2 version and make it better and have all batteries isolated from each other and wanted to make sure what the best method or way was to go about it, the reason I asked here, I'd have one controller and 4 slaves that sent all data to the master.
Early test's show that this charger does help improve the runtime which means that it is breaking down the lead sulphate crystals in the battery. I wanted to make a start so if this did take off I could build more of them for our company as an in house tester but the project has been put on hold for the time been as our company saying it's to time consuming and they need to look into it more before they decided
Shame as it would have been an interesting project to work on again, If it was not for that other company trying to come up with an all singing all dancing version my other design would of been made but again because of all the faults and time they stopped it.