Theunis Prinsloo

Hi Harry my electronics knowledge is quite limited - I can build and test n circuit thanks to YT ect.. But the intricacy's of component values etc. not well versed. I more or less know what to do but to get there is the dilemma. 1. will need to use the pack voltages of 24 vdc via n ± LM7805 circuit to drive the BMS's on each of the batteries. 2. Then a censing circuit to read the cell voltage 1.140 v adjustable (preferably multiturn pot) and use this to activate the BMS in 1. to balance each cell. 3. I think both circuits need to be isolated from each other by an OPTO or something. If you have something in mind would be appreciated TP

Hi Harry - thanks for knocking on this door ! 😁 Thanks for getting back. I have the system connected to an 3Kw invertor so the charging is not the problem. I need to balance the batteries while they are charging and while on float. I have an idea how it should work but I'm not n electronic wiz so need n bit of assistance on the build. Taking the above example should work I need small change to this circuit to get it to read n 1,4 volt cel instead of the 3.7 v cell. any assistance would be appreciated. Thanks TP

Hi Guys - your help here is highly appreciated ! I have 20 x NiCad (flooded cells) of 1,2v 32Ah each, wired in series into a 24v bank. Float voltages per cell is 1.40 - 1.42 V/cell. (I actually have 80 cells connected in 4 x 20 cells each iaw for a total of 128 Ah) Have looked at off the shelf BMS's but is above my pay grade - (and really only need balancing) A simple but effective circuit that I can build to balance each cell would be appreciated. I had a look at the attached circuit found it on YT - something similar should be able to do the job. I am aware that the cell voltage of 1.4v is very low for most components to function on - will mean that 24v from the bank will be needed to power the circuit Any ideas please share - Thank you for your interest and help in this project TP