ECO-WORTHY 12V 300AH Battery Balancing Issues

[f-tx]

I recently picked up an EcoWorthy 300Ah LiFePO4 battery and I’m running into some cell balancing issues that I could use some help with.

The problem:

• When I charge the battery to 100%, some cells go higher than others instead of staying even.
• I’ve noticed the BMS isn’t doing a great job keeping them balanced at the top end.
• Below ~13.5V things look more even, but near full charge, the imbalance shows up.

My setup:

• EcoWorthy 12V 300Ah LiFePO4 battery (with the stock BMS).
• NOCO Genius 10 charger (only 10A).

Questions I’m trying to figure out:

1. Is this normal behavior with EcoWorthy batteries, or is mine defective?
2. Does the stock BMS even balance actively, or only passively at a very low current?
3. Would using a higher-amp LiFePO4 charger help with top-balancing? If so, what chargers are recommended?
4. Has anyone tried updating/replacing the EcoWorthy BMS?
5. Would adding an external active balancer be the best solution here? Any specific models you’d recommend?

Any help will be appreciated I need to use these battery tomorrow.

 

[Sparkyaz]

Higher amperage won’t help, as top balancing doesn’t use much. The cells are already full.

By how much is the imbalance?

One cell or multiples?

What is your voltage settings?

How long do you let your batteries absorb? As in once full, how long do they balance.

And how are you gathering this information?

 

[RVguy604]

I just finished charging my EcoWorth 280ah battery for the first time and there are some voltage differences in the cells. The app says it’s “normal”. How much are your batteries off by? Like you, I used a Noco charger, but 20amp.

 

[Supervstech]

At low amperage, 3.4v per cell is 100%.
A cell can be charged to 3.65, but it will not stay there, it will settle around 3.4ishv per cell.
I set my charger to 3.45v per cell and run till they stop balancing.

 

[RVguy604]

I ran the charger until it shut off, those were the values above. Then I put a low 110W draw on the battery and checked the cells after 10 min. Then a few minutes later. Looks like they are evening out around 3.33v while under the 100W+ load. The odd thing is that the battery dropped quickly to 277.2ah and still shows 277.2 AH remaining for the last 20 minutes… I guess it’s not very accurate.

 

[mikefitz]

Below ~13.5V things look more even, but near full charge, the inbalance shows up

The cell deviation will only show up at a cell volts over 3.45, 13.8 battery volts.

Is this normal behavior with EcoWorthy

Yes, when the battery is new, balance will improve with time.

stock BMS even balance actively, or only passively at a very low current?

Passive, low current.

Would using a higher-amp LiFePO4 charger help with top-balancing? If so, what chargers are recommended?

A higher charge current won't help. A charger with user charge profile settings is recomended.
By applying a constant lower charge voltage, typically 13.8 volts for a 12 battery, for several hours, the balance process has time to work.
Automotive low current chargers, like the NOCO, aren't ideal , with a fixed high charge voltage, the battery will be overcharged
The Victron Smart range of AC chargers are recomended, fully programmable and will operate in charger or power supply mode. ( look at the IP22 or the IP67).

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You cannot add an active balancer without taking the battery apart to acess the cells.

There is nothing wrong with the battery. Either continue to use the battery, idealy with a lower charge voltage, (14.2 volts maximum), or to speed up the process, connect a power supply or Victron charger set to a lower charge voltage.

At a fully charged condition, there will a cell difference. If you can get a balance with a difference of 20mV, with all cells reaching 3.50 volts under charge, then that's acceptable. (14.0 volts battery voltage).
What is more important is that the battery has rated capacity.