Battery Vehicle Society

I have been working on a SOC routine that will account for the peukerts effect that affects lead acid batteries. Using the manufacturers data for my batteries I have done some number crunching and come up with a few lines of code, which I'd like to share with the forum. As part of the process I used...

Maybe it was me who emailed you Peter. I am modifying an older version of the code though. Here is what I sent. ******* I hit a snag with the alarm and warning bits. The charger wouldn't switch off using the relay when above AbsMaxCellVoltage, so I used the debug to see what was going on with the wa...

I am using version one of the master board, it has 3 spare ADC headers on the board. I am using one for the buttons, one to read an LM35 temp sensor for the Zilla Heatsink, that leaves one spare if I decide to use a small current sensor for the charger. I will be using the controller cutback output ...

I have been thinking about what Mark said. When using two ADC inputs was mentioned, it came to me. Why not just use two current sensors, a meaty one on the pack and a weedy one on the charger lead, sounds like a cheap and easy solution.

Derek

Hi Peter, It's the LEM sensor I bought from you ages ago with the +15 -15v dc-dc converter. It outputs +4 -4 for +400a -400a. If it's not too expensive I might be quicker and easier to obtain a 0-5v sensor. I have set the battery current limit on the controller to 450A. I could use the sensor I got ...

Hi, I have not been following the thread for a very long time, I would never have thought all the other stuff involved in building a car would be so time consuming! I see things have progressed greatly since the early days. I am now back to working on my version of Peters BMS. I will mention a few m...

Thats what the capacitors inside your controller are for. If you put extra capacitors in yourself between the contactor and the controller you will need some kind of precharge circuit otherwise your contactor will be at risk of premature wear due to arcing of the contacts.

Hi Peter, I have bought some clip on ferrites to use on the data cables (cat5) on my BMS. Perhaps these would offer extra protection for your insight interference problem? These are identical to mine but I got them at £1 each Item number: 250456860850 Just wish I could clear up my mechanical backlog...

Those prices sound very cheap, what kind of batteries are you looking at and what companies?

D

The software should be broadly similar but I won't need to do the complicated bit for calculating the voltage using ADC. Peter is having to overcome the fact that the ADC reading is relative to the picaxe supply voltage so he's had to be a bit clever. I am using a regulated 5v supply so I needn't co...