I want to make my own BMS

[Pidjey]

Another reason is that I am renovating my system and provably I will move from an integrated charger inverter that can only work with common port BMS to dedicated separated charger and inverter where I can use split port for charge and discharge. For this reason the design will change a bit.

My new eve cells are arriving on Wednesday and I need to take a decision soon.

 

[John Frum]

Another reason is that I am renovating my system and provably I will move from an integrated charger inverter that can only work with common port BMS to dedicated separated charger and inverter where I can use split port for charge and discharge. For this reason the design will change a bit.

My new eve cells are arriving on Wednesday and I need to take a decision soon.

So your design will be separate port?

 

[Pidjey]

I do not know yet. I need to check what is in the market in terms of solar chargers and inverters to replace my charger/inverter.

I am sick of my charger/inverter. As I am renovating the batteries I am thinking on getting rid of it and have a system that allows me going with separate port.

Actually I was also thinking to make something universal. As the only difference is the arrangement of the mosfets maybe I can do a trick with busbars in order to allow both configurations for the future.

 

[Pidjey]

Or maybe I just stay with common port even for separated port system to make it simpler.

 

[Pidjey]

This is how it looks like what I have ordered. Let's when everything arrives. For the first version I have decided to have the MCU externally connected ussing I2C. I also removed reverse polarity protection for simplicity. I do not expect during my initial tests to make this error.

 

[SammyMc]

nice project
did you get it to work after all ?
regarding BQ34z SOC chip , it is really an accurate chip but it does not like pulse loads if you have any

 

[Pidjey]

Actually yes. Due to personal and professional reasons I did not have to write a feedback here.

The systems also in my parents house in a different system so this Christmas when I visit them I will write a review.

About the BQ34z I have not worked with it anymore because of the time. In any case I wanted to implement my own algorithm but I have not found a reliable way from the perfectionist point of view.

 

[SammyMc]

Actually yes. Due to personal and professional reasons I did not have to write a feedback here.

The systems also in my parents house in a different system so this Christmas when I visit them I will write a review.

About the BQ34z I have not worked with it anymore because of the time. In any case I wanted to implement my own algorithm but I have not found a reliable way from the perfectionist point of view.

glad to know that it worked after all
please give feedback about the circuit , a lot of us are on the same boat and the TI 76952 looks promising

regarding SOC , there is an algorithm in mind (coulomb counter + modified OSV). if you decide to continue your venture we could continue here .
regards