timselectric
If I can do it, you can do it.
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4 at $1200.
For $300 more, you could have an 48v EG4.
And, no headaches.
For $300 more, you could have an 48v EG4.
And, no headaches.
Is battery equalizer required for batteries in series?
- Thread starter Riley
- Start date
EG4 comes out right after my zooms order.
Unfortunately I had to have low temp protection in my situation (it has already saved my bacon once) These batteries just barely fit in the only space I have to put them and I needed to have them in 48v series configuration. I needed the batteries in a short time. I was really glad I was able to get these and that they actually worked.
Unfortunately voltage is not a good indicator of state of charge for a lifepo4 battery. The balancer is supposed to transfer up to 10 amps per hour between batteries ( I have no Idea how they calculate that) I charged my batteries as high as they would go and then put a small dummy load on the persistently high voltage battery to even it up with the others and then connected the balancer ad hoped for the best.
I would have done that in a heartbeat if it would have fit and I could have gotten it in time. I almost built a battery but I didn’t have the time.
timselectric
If I can do it, you can do it.
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?
WYtreasure
It's not happy hour, I'm just like this.
And the conversation was going so well.
Translate:
Yes, the lifePO4 battery can be connected in parallel to balance voltage, and then connected in series.
WYtreasure
It's not happy hour, I'm just like this.
Thanks for translating. That is good to know.
Last edited:
I'm convinced that putting 12 volt LiFePO4 batteries with a BMS in series is doomed to fail. Yes, a balancer will usually keep the batteries closer to the same voltage. But if a single battery of the desired voltage had been created from the start, a third party balancer wouldn't be necessary.
timselectric
If I can do it, you can do it.
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The balancer is just a bandaid, to be placed on the boo-boo of having the wrong battery. lol
wattmatters
Solar Wizard
I have a HA02 balancer on each of my 4 x 12V SLA battery banks and they do a good job but can't say how well it would perform with LiFePO4.
Except at low and high SOC levels, LiFePO4 has a very flat voltage-SOC relationship meaning balancing based on voltage alone may not be sufficient - but at least it should help reduce the scale of the imbalance - 13.3V vs 13.9V is quite a big difference in LiFePO4 land.
Except at low and high SOC levels, LiFePO4 has a very flat voltage-SOC relationship meaning balancing based on voltage alone may not be sufficient - but at least it should help reduce the scale of the imbalance - 13.3V vs 13.9V is quite a big difference in LiFePO4 land.
yes but a bandaid on the wrong battery is better than no battery at all and that is my situation. I’m pretty please with what my batteries do for me
WYtreasure
It's not happy hour, I'm just like this.
So now I have 4, off the shelf, 12V LiFePO4 200Ah batteries and a 24V All-In-One.
Is it advisable to use the bandaid and plan on disconnecting a few times a year for balancing?
Is it advisable to use the bandaid and plan on disconnecting a few times a year for balancing?
If the batteries are good and if you properly balance them using a 12V charger before you ever put them into your system (in 2S2P in your case) then you shouldn't need the bandaid and you probably will only need to rebalance at most once a year. I have two batteries in series. They have been so for almost 10 months now I think. They are still at the exact same voltage.
The balancer is a permanent solution, not a temporary patch. The balancer can also take the place of the initial top balance.
2 in series is not as complicated as 4 in series.
timselectric
If I can do it, you can do it.
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Do the initial balance, and use the balancer to keep everything happy. Check voltages a couple times a year. Shouldn't have to do anything else.
I am presently seeing if I can get my batteries closer to internally balanced without disassembly of the bank. I have 4 of the global power batteries in series connected with an active balancer. I have reached cutoff voltage. The batteries specs are 14.6 volts for cutoff but each battery is cutting of at about 14 volts. I have my charger set at 5 amps the voltage on the batteries reads even at 13.6 gradually increasing to about 14.2 volts and rapidly falling to 13.6 and repeating. The charger shows less than 1amp output to the batteries. The voltage on the batteries individually is virtually identical. I expected to see a spike on the disconnecting battery but I’m not getting that. Perhaps because of the active balancer?
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