Imbalance in battery cells of a freedom won

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davon asked Oct 6, '23

Imbalance in battery cells of a freedom won

Hi Folks

I am looking for some assistance please. I have a Multi RS6000/450-100 Inverter running on two Freedom won 10/8 batteries. during the charge and discharge cycle the battery cells are balanced but as it reaches the 100% charge 55.8 volts for freedom won, the cells go out of balance as indicated. The cells stay out of balance until the battery starts its discharge cycle. we see this problem on two deferent sites running exactly the same equipment.

any information will be welcome

Many thanks

Multi RS freedom won

screenshot-2023-10-06-111429.png (54.6 KiB)

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Answer 1 · 2023-10-06T09:30:23Z

nickdb answered · Oct 06, 2023 at 09:30 AM

How new is the battery and how long is it left at full SOC?

Variations in cell voltages only really occur at top of charge and bottom of discharge, so that is entirely normal.

It can take quite a while to settle, depending on how you use them.

If they get little time at full charge then it will take much, much longer.

Advice is usually to leave on keep charged for a while, though I have not had much luck with that, deeper discharge cycles also do help, but generally just needs time.

They also have issues with older and newer batteries in parallel, so if you see SOC jumping up then you are part of the lucky bunch to be affected.

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Answer 2 · 2023-10-06T09:46:17Z

davon answered · Oct 06, 2023 at 09:46 AM

Hi Nick

the batteries are new and have been kept charged for at least 24 hours at a time. they have not been discharged below 20%SOC yet.

Many thanks for the info we suspected it was the case of a new battery that needed to be cycled, but wanted to be sure we did not miss something and damage a battery

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nickdb ♦♦ commented · Oct 06, 2023 at 09:49 AM

If it gets to spend enough time balancing at higher SOC it should sort itself out in a month.

You will notice it varies the CVL as it hits imbalances and at higher charge levels. These CVL swings tend to be less varied as it becomes balanced, so keep an eye on that as well.

You should see a trend over time if you look at a wider chart range on VRM.

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davon nickdb ♦♦ commented · Oct 06, 2023 at 09:56 AM

many thanks

Will do

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