Do I need to balance my batteries for my 24v system? If so, how?

[dtrask]

I bought an MPPT LV2424 and two 12v BigBattery OWLS. I have yet to hook them up due to a long shipping delay and now it's wintertime. I'm using them in a van build. Once it warms up, I want to get moving on the installation. I'm hooking the 2 BigBatteries OWLs into series to accommodate 24volts. The batteries will have been sitting for a few months in the box. My question: Do I have to balance the batteries when installing them into the 24-volt configuration or will the MPPT LV2424 do it for me? I just want to make sure I do it right and get the most (without being ridiculous) out of my batteries. Any advice is appreciated. (Basically, all I have to charge the batteries is the MPPT LV2424...I don't have any other chargers)

 

[Bubba1]

You need to balance them. You can't do it with the charger you have. What is the voltage of the batteries now. You should probably be testing them out now in case there is any issues with them.

 

[rmaddy]

See Will's recent video:

 

[joanna_lannie]

Refer to LiFePO4 battery balancing.
My personal opinion is that it's better to use a balancer, it can save you a lot of trouble. Although a lot of things like chargers and BMSs claim to support battery balancing, you know the difference between a phone's camera and a real camera.

 

[Don B. Cilly]

Haven't you got any solar panels?
If you do, you could just get a reasonably cheap SCC, charge the batteries separately to pretty much the save voltage, and keep it as a spare.
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[2Vets]

Refer to LiFePO4 battery balancing.
My personal opinion is that it's better to use a balancer, it can save you a lot of trouble. Although a lot of things like chargers and BMSs claim to support battery balancing, you know the difference between a phone's camera and a real camera.

what balancer/charger would you recommend for raw cells before connecting them, or just connect them and do 12v?

 

[toms]

Make sure you charge them individually to full (at 12V), also leave access to be able to periodically charge the batteries individually as they inevitably get out of balance.

You don’t need to disconnect the batteries, just make sure all loads are removed and individually top up each battery

It is one of the downsides of multiple batteries in a system.