Li Time battery in parallel with Ography

Lysdexicuss

Would there be a problem if i connected two different brands of LiFePO4 batteries in parallel to the same pv array/charge controller ? 

They are both 12v 200ah

thanx

BB.

As a starting point, if both batteries are at the same state of charge (terminal voltage), then yes they can be paralleled--If the batteries are not at the same state of charge, you can have high current flow from one battery to the other (Lithium Ion Batteries have very low internal resistance--So there can be high current flow between miss-matched SoC batteries).

Second, there are many different types of Li Ion batteries out there (naked cells, batteries with internal battery management systems, etc.)... You should find the manual and see what it says.

-Bill

BryceFreeman

Even they share the same volt and ah it is still not recommended. The voltage change rate of their cells are different, which may lead to unexpected current difference in some situations. Avoid this by choosing the same brands of batteires will be better.

Horsefly

I ran much of this year with a 160Ah 24V battery in parallel with a 230Ah 24V battery. I built both of this LiFePO4 batteries. Several times I used a clamp meter to check the charge and discharge for both batteries, and although the currents were sometimes not quite proportional to the Ah ratings, it all ended up balancing out with no issues.

There are a number of people who have had different LiFePO4 batteries of the same voltage in parallel for years. Doesn't cause a problem.