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Full Version: 64/128 cells - DIY Multi Battery Tester Charger / Discharger
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Hi,

I decide to make an multi battery tester module. I think a lot of people will deal with this problem, dont have time to test a big number of cells.
My charger will be a smart charge up to 128 cells. Will report by email and web server when the cycle are completed.
I will document this work on youtube and also on my PowerWall thread!

Best regards.
 

First of video from the series: - sorry for my english is not very good!
 
Parts

 
Schematics


Anslabled Boards


Test Unit Video



32 Cells Working Module 



Constant Current vs Constant Load

       

Constant Current with variabile resistor theory

        


Constant Current with constant voltage controlled by arduino PWM  - Parts & Schematics 

       

Constant Current Complete Boards



Software: V0.3 Beta

All Software will be on: http://www.diypowerwalls.com/t-Constantin-PowerWall
That's practically exactly what I was wanting to do Smile I really like this work! Nicely explained and laid out Smile Nice walk-through. And your english was just fine!

However, why don't you use an A2D (I think this is what it is) with I2C interface for the analog reading. Wouldn't that allow you to read all the values somewhat at the same time?
Though, I do like the CD4052B variant, as it looks to me like it has 2 leads that switch from pairs of pins at a time (pin 1&2, then 3&4, then 5&6, ...). This would effectively isolate the grounds, yes?

Now, could we use a digital mux for the fets? Reason I ask is cuz I have nano's and would like to use what I already have.

I did notice that you didn't post the code anywhere. I think I can follow the schematic based on what you showed in the video, though.
Test Unit Video

Looking good! Smile
32 Cells Working Module 

Very Nice
Looking good.
By the way, it wouldn't be too difficult to make the dis-chargers constant current, you've almost got everything there already.
(09-12-2017, 06:13 PM)SimonW Wrote: [ -> ]Looking good.
By the way, it wouldn't be too difficult to make the dis-chargers constant current, you've almost got everything there already.

Yes i will make the other 32 module with constant current discharge. in few days. And after that i will make an comparation.
(09-12-2017, 07:19 PM)mrconstantin Wrote: [ -> ]Yes i will make the other 32 module with constant current discharge. in few days. And after that i will make an comparation.

Cool, I look forward to seeing how you go.
Just one extra resistor and an NPN transistor, maybe also change the 10 ohm so you get a higher current draw toward the end(say 500mA instead of your 250mA with the 10 ohm), and you're set.
The mosfet will go from being a switch to an automatic variable resistor Big Grin
Would need some heatsinking, but it's only a few watts per mosfet.
(09-13-2017, 03:54 AM)SimonW Wrote: [ -> ]
(09-12-2017, 07:19 PM)mrconstantin Wrote: [ -> ]Yes i will make the other 32 module with constant current discharge. in few days. And after that i will make an comparation.

Cool, I look forward to seeing how you go.
Just one extra resistor and an NPN transistor, maybe also change the 10 ohm so you get a higher current draw toward the end(say 500mA instead of your 250mA with the 10 ohm), and you're set.
The mosfet will go from being a switch to an automatic variable resistor Big Grin
Would need some heatsinking, but it's only a few watts per mosfet.

Simon, would you be willing to sketch out the placement of the additional resistor and transistor based on his initial design? I have all the parts coming my way to build out his initial design. Thanks!
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