2 batteries - 2 experiences

[chrisblessing]

Greetings. I'm decidedly new at this, but have now completed two DIY battery banks. One is a 12v 90Ah, the other 12v 120Ah. The 90Ah was my first attempt, using 90Ah K2 cells. I employ an Eco-Worthy 40a charge controller. Because the battery would not fit in the compartment on my camper, I decided to build a 2nd battery. The 2nd one employs a Rich Solar 20a solar charger.

Both batteries have what I think is called a "resting rate" of about 13.3v per cell or 13.2v, which I take is just fine. However, when charging the 1st set can reach up to 14.6v (3.8-4v per cell) while the 2nd doesn't go over 13.4v. I have been checking both each morning before charging resumes and both batteries are nearly identical at about 13.6.

I'm attributing the variances to differences between the solar charge controllers but would like input. I am concerned about the 1st battery reaching such a high voltage.

Thanks for any insights.

 

[SolarRat]

Are both dip-switches on the Eco-Worthy in the up/on position for LifePo4?

 

[chrisblessing]

Are both dip-switches on the Eco-Worthy in the up/on position for LifePo4?

Yes they are. This charge controller has overcharge protection and the cells are remaining well-balanced, so this is a mystery.