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Battery Balancer for lifepo4

hongning

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Mar 26, 2022
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I am planning to change from a 12V to a 24 Volt system. I plan to hook up (2) Ecoworthy 12V 100AH lifepo4 battery in a series to make 24V.

I believe I read that I will need a Battery Balancer.

Anybody ever used this PowMR 24V Battery Balancer


I just prefer this over the Victron Battery Balancer as Victron dissipates power, compared to moving the power.

Any comments or ideas on why I should use Victron or even if its applicable for a LifePO4 batteries

Thanks in advance
 
You shouldn't need a battery balancer. The trick is to properly balance the two 12V batteries before you put them in series. If done correctly you shouldn't have any problems after that. Worse case you might need to rebalance the two batteries once a year.

Start with a good LiFePO₄-friendly 12V battery charger. Fully charge one 12V battery. Fully charge the other 12V battery. Now connect the two batteries in parallel (not series). Then connect the 12V charger so one lead is on one battery and the other lead is on the other battery. Fully charge. Disconnect the charger but leave the two batteries connected in parallel over night.

You now have two equally charged and balanced batteries. Connect them in series for your 24V system.
 
I would hold off to see if this is even an issue.

Upgrading from 12 to 24V is inconvenient and spendy enough.
You shouldn't need a battery balancer. The trick is to properly balance the two 12V batteries before you put them in series. If done correctly you shouldn't have any problems after that. Worse case you might need to rebalance the two batteries once a year.

Start with a good LiFePO₄-friendly 12V battery charger. Fully charge one 12V battery. Fully charge the other 12V battery. Now connect the two batteries in parallel (not series). Then connect the 12V charger so one lead is on one battery and the other lead is on the other battery. Fully charge. Disconnect the charger but leave the two batteries connected in parallel over night.

You now have two equally charged and balanced batteries. Connect them in series for your 24V system.
Thank you for the tips, I would do that.
 
Suggest you consider getting a couple of DC cheap meters, of any sort, and connect them, one to each battery. Keep any eye on them during normal use. If you see one trending higher voltage (at full charge) than the other, you can drain the high one down a bit to get them closer together.
 
Suggest you consider getting a couple of DC cheap meters, of any sort, and connect them, one to each battery. Keep any eye on them during normal use. If you see one trending higher voltage (at full charge) than the other, you can drain the high one down a bit to get them closer together.
Thats a good tip Thanks
 
Suggest you consider getting a couple of DC cheap meters, of any sort, and connect them, one to each battery. Keep any eye on them during normal use. If you see one trending higher voltage (at full charge) than the other, you can drain the high one down a bit to get them closer together.
Another option is to use something like a Victron SmartShunt or BMV-712. Since having a shunt and battery monitor is useful in its own right, you may already be planning on one. They have the additional feature of being able to do mid-point battery monitoring when you have two batteries in series. I have this in my system (24V made from two 12V batteries). These particular battery monitors can alert you if the voltage difference between the two batteries becomes greater than a chosen threshold.
 
Another option is to use something like a Victron SmartShunt or BMV-712. Since having a shunt and battery monitor is useful in its own right, you may already be planning on one. They have the additional feature of being able to do mid-point battery monitoring when you have two batteries in series. I have this in my system (24V made from two 12V batteries). These particular battery monitors can alert you if the voltage difference between the two batteries becomes greater than a chosen threshold.
I have a SmartShunt (great product). I was not aware it has a mid-point connection. I have not need, so didn't look that close. Nice to know.
 
I use the Victron Battery Balancer on my 2 LifePO4 Batteries and it works well. I did all the steps of top balancing, but having a balancer is worth the money IMO. I made of installation and review video of the balancer here.

Please let me know if this is not allowed and remove post. I'm just trying to help.
 
G
I use the Victron Battery Balancer on my 2 LifePO4 Batteries and it works well. I did all the steps of top balancing, but having a balancer is worth the money IMO. I made of installation and review video of the balancer here.

Please let me know if this is not allowed and remove post. I'm just trying to help.
Great post and the video was very insightful. Are you using the Victron GX system to get those reports?
 
@JayEmmEll question, my battery balancer on my 24v system makes a bunch of clicks when it's doing its thing. I'm wondering if yours does the same or if possibly I have a unit with an issue.

Here is a video of it in action:


I appreciate any help you can provide.

Thank you!
 
You shouldn't need a battery balancer. The trick is to properly balance the two 12V batteries before you put them in series. If done correctly you shouldn't have any problems after that. Worse case you might need to rebalance the two batteries once a year.

Start with a good LiFePO₄-friendly 12V battery charger. Fully charge one 12V battery. Fully charge the other 12V battery. Now connect the two batteries in parallel (not series). Then connect the 12V charger so one lead is on one battery and the other lead is on the other battery. Fully charge. Disconnect the charger but leave the two batteries connected in parallel over night.

You now have two equally charged and balanced batteries. Connect them in series for your 24V system.
@rmaddy 's advice above is excellent. I run 16 100ah Battleborns in a 4P4S configuration and have 3 Victron balancers on the system and I can tell you from experience, there is NO WAY in HECK they could keep this system balanced if I didn't do a good bottom or top balance first. I had to get 4 of them replaced during the last couple years (4 of the batteries, not the balancers) and due to time restraints just threw the replacement batteries into the system as I did not have time to to a full balance for the new batteries, wow did I pay a price for that.... Don't think you can charge up till the voltage appears the same as the other one, the curve is too flat, voltage means very little with liths, it is for sure no way to determine compatibility to another battery in the system. Take the time to do a good balance, THEN and only then buy a balancer, take it from someone who pulled her hair out trying to resolve it with balancers cus I refused to make the time to drop the system down (I work full time from home and live off grid).
 
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@JayEmmEll question, my battery balancer on my 24v system makes a bunch of clicks when it's doing its thing. I'm wondering if yours does the same or if possibly I have a unit with an issue.

Here is a video of it in action:


I appreciate any help you can provide.

Thank you!
I have three of those balancing 16 100ah's in a 4P4S and I have NEVER heard a relay and never seen the LED's flash like that.
 
I have a SmartShunt (great product). I was not aware it has a mid-point connection. I have not need, so didn't look that close. Nice to know.
I was running my optional connection on my Victron BMV-712 as a temp sense but decided to try it as a midpoint v sense on a 48v 4P4S config and wow am I glad I did. It's almost like a fetish now seeing how close I can get my cells to balance. Try it, it's a lot more interesting than temp and you can get temp with other sensors (your MPPT, an optional temp sens etc).
 
I was running my optional connection on my Victron BMV-712 as a temp sense but decided to try it as a midpoint v sense on a 48v 4P4S config and wow am I glad I did. It's almost like a fetish now seeing how close I can get my cells to balance. Try it, it's a lot more interesting than temp and you can get temp with other sensors (your MPPT, an optional temp sens etc).

Sounds familiar.. Better build a dump system and enjoy. The more sensors and readings you have, the more the geek inside you wants to keep track of all the data ;)
 
Sounds familiar.. Better build a dump system and enjoy. The more sensors and readings you have, the more the geek inside you wants to keep track of all the data ;)
Yup, energy storage doesn't always mean batteries, sometimes it means hot water. :)
 
OK so if I have 4 12v 100 ah batteries and follow the process as @maddy above (charging each with one a 12v charger)..

Then I have now the option to put them into series
4S = a 48v 100 ah system.. this means I can discharge and charge really fast
4P = a 12v 400 ah system.. its like a bigger 400 ah 12v battery...
2P 2S = a 24v 200 ah system... something in between the 2 above

Since I just plan to charge and discharge using my ECO DELTA PRO... I could just keep it in series and let it slowly charge up my eco flow and continue to be charged by a 12v charger? or even a 12v solar charger?

Thank you for any help
 
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