Balance 2-280AH Batteries

[the1adman]

I have tried searching and can't find an answer to my question. I have 2 Eco-Worthy 280AH batteries. The cells balance ok up to about 3.37 then one or two will take off. I purchased an adjustable DC regulated bench power supply ( https://www.amazon.com/dp/B0CLY9B5XL?ref=ppx_yo2ov_dt_b_fed_asin_title&th=1 ) to hopefully top balance them. I downloaded the Overkill Solar app and set the BMS settings to their recommendations in their manual. I charged the batteries individually to the same voltage and SOC. My plan was to connect them in parallel as I indent to use them and use the bench power to slowly top balance them.

1. I don't know where to start volt and amp wise. I was thinking 13.8v and 5a and go up 1v at a time from there if they stay balanced?
2. Should I balance them individually to 100% SOC then connect in parallel instead of both at one time?

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[Supervstech]

The BMS should balance the runners over time.
What are the BMS settings you have?

 

[the1adman]

Here is a screen shot of my settings.

 

[Pompano Jig]

You're not alone, I have roughly the same setup - 2X280 ah Eco-worthy batteries in parallel. One without blue tooth purchased last July and one with purchased in December.

I have the same cell imbalance issue as well. I was never able to get more than about 240 ah according to their BT app and it would stop charging (or the Victron MPPT would stop it - absorption was set to 14.2 volts).




Imbalance starts around 3.40 volts and from there cells 1 & 2 are off to the races.

I changed the absorption to 14.3 on the MPPT yesterday and somehow I magically have 280 ah now and SOC looks a lot better? Note that cells 3 and 4 are still lagging.




Is this typical or acceptable? I have the same questions about finding a solution. This is my first solar setup.

 

[the1adman]

I found that changing the BMS settings helped a lot. The factory settings do not work to well. The balancing start voltage is to low and the cell max voltage is to high. I used the Overkill Solar manual settings. https://overkillsolar.com/product/1033/amp/

 

[the1adman]

I followed @Supervstech instructions to let the BMS balance it. I let it rip overnight at 14.4V and 30A. This morning both batteries were 100% 14.07V cells at 3.52V +\- 0.010. The difference this time that worked was the BMS settings change.

 

[Pompano Jig]

Awesome, thanks for sharing that. I'll check out the link you sent for the manual settings. Glad it worked out for you!

 

[DaveM]

Here is a screen shot of my settings.

How did you get to these settings? Was that within the eco-worthy app, or are you using something else to tweak the settings? I just got four of these batteries and would like to get them optimized as much as possible. I didn’t see anything that granular in the app.

 

[Pompano Jig]

How did you get to these settings? Was that within the eco-worthy app, or are you using something else to tweak the settings? I just got four of these batteries and would like to get them optimized as much as possible. I didn’t see anything that granular in the app.

You can just install the overkillsolar app on your phone. It is much better than the eco worthy app.

 

[DaveM]

You can just install the overkillsolar app on your phone. It is much better than the eco worthy app.

Thanks. New to this, so that information is very helpful. I will check it out.

 

[the1adman]

I installed the Overkill Solar app which allows you to change the BMS settings. I am new to this as well and have spent a lot of time on this forum learning.

I think Eco-Worthy are good batteries for the money. The factory BMS settings need adjusting making it more usable.

 

[Pompano Jig]

I haven't been able to get a full charge the last couple of days, only up to 95% so not able to make sure all the cells balance out at the top end. Hopefully it will happen in the next couple of days?

I found this too. I thought it might be of interest since we all own the 280 ah EcoWorthy batteries. They actually have a video showing you how to take apart the battery. I thought most companies tell you not to take it apart, this was def interesting to see:

 

[the1adman]

I haven't been able to get a full charge the last couple of days, only up to 95% so not able to make sure all the cells balance out at the top end. Hopefully it will happen in the next couple of days?

I found this too. I thought it might be of interest since we all own the 280 ah EcoWorthy batteries. They actually have a video showing you how to take apart the battery. I thought most companies tell you not to take it apart, this was def interesting to see:

Did you change your BMS settings? What voltage and amps are you charging with?

 

[Pompano Jig]

Did you change your BMS settings? What voltage and amps are you charging with?

My two batteries in parallel so still 12.8 volts. My SCC does 45 amps max at that voltage.

I haven't changed any settings yet (on the BMS), still trying to see if anything different once it gets close to topping off.

 

[the1adman]

My two batteries in parallel so still 12.8 volts. My SCC does 45 amps max at that voltage.

I haven't changed any settings yet (on the BMS), still trying to see if anything different once it gets close to topping off.

I had to charge at a higher voltage to get it to balance. Are you charging at 12.8 volts? That is to low if so.

 

[Pompano Jig]

I had to charge at a higher voltage to get it to balance. Are you charging at 12.8 volts? That is to low if so.

Oh sorry, I misunderstood. Currently charging to 14.25 but that is set on the Victron SCC, not the battery BMS.

I only charge with solar so not having luck last few days to top off the battery while running normal loads.