3S lipo with different volts per cell. Example: (4.11 3.92 3.93)

Hello guys, a short question:

One of my my two 3S 5000mah lipo battery has been a little strange for a while.

I don´t know why 1 cell is up to 0.10V higher than the others 2 cells. I´ve be running with this battery more than 2 months and suddenly this started to happen .

i´m using IMAX b6 original; i charge it with 3.0A in Lipo Balance mode my battery cut off is set to 3,7 per cell on the VESC

my two question are: 1)Is this normal to happen? 2)If isn´t normal, this could be a problem? 3)And if is a problem, can be fix?

thanks

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That’s not 0.1 above, that’s ~0.2. You need to balance that asap. The IMAX-B6 should have a balance feature. Once balanced,recheck. If the lipo doesn’t stay balanced out, I would discard it.

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i forgot to mention that i always charge in Lipo Balance mode. i thought it was something with the amps , so i tried charging with 1.0AMP but i didnt get any sucess, they still UNbalance

Use your balance charger to check the internal resistance (IR). They shouldn’t be that far off

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i google it about IR and i realized that my imax b6 (is very old) doesn´t have this option… maybe it is a fake imax?:face_with_raised_eyebrow:

use the discharge function and charge again could be an alternative to bring back the balance between cells?

It would help to have more info about your batteries. Brand? C rating? When Lipos get worn, there internal resistance will increase but it’s not likely to increase evenly across all cells. This will cause the cells to charge and discharge unevenly. If you are using Lipos with a low C rating like 10-25C then the high current demand of esk8 can cause them to age quickly. Does the pack in question show any signs of swelling? Is your charger stopping the charge cycle with those voltages 4.11 3.92 3.93 ? It should continue to charge until all cells reach 4.2v When cell one reaches 4.2 it will just idle while the other cells catch up. Thats how a balance charger works.

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thanks for your answer

Brand? a:HRB ( bought on ali express), this battery has at least 5 years, (not continuos using) and was used just for TRAXXAS RC .

C rating? a:50C discharge/100c burst

Does the pack in question show any signs of swelling? a:Yes, i dont know if you can see in the picture, but the first cell is a little fluffly ( im sorry, i dont know a better word for this) and when it come close to 3.50/3.60 this cell gets totally swelled and very very hot. but i always stop in 3.74/3.75

Is your charger stopping the charge cycle with those voltages 4.11 3.92 3.93 ? a:No, i am able to full charge all cells to 4.20, the only thing is that cell in question stay in 4.19/4.20 till the others gets to 4.20

It should continue to charge until all cells reach 4.2v. a: yes

the charging situation was perfect until this week. i didnt do anything different that i usually do, didnt change any configuration on the vesc etc etc

Never heard of that brand so I can’t comment on their quality. The pack does look well used and if it got hot enough to melt the shrink wrap, then there could be some deterioration of the cells. Be really careful about the heat issue. Getting batteries like these hot can cause a dangerous situation.

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Those batteries are beat! Personally I would replace them

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i´ve never had another battery so i also cant comment about their quality haha i was buy a turnigy graphene,

so i guess this voltage difference is not a issue ?

and i guess it would be good buy a fire retardant lipo battery bag

i already have done this… i am still waiting for the new ones… i wanted to buy the turnigy graphene, but they dont ship to Brazil, in fact just a few brands ship to here. so the only solution from us is to buy this kinda of chineses brands (nothing against China products) but you got the point…

The voltage difference is not such a big issue but the batteries getting hot is.

You should be able to get batteries from Hobby King’s Global warehouse.

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Mines are similar to this ? Ones like 4.11 and the others are like 3.98. Should I discharge them to like 3.2 then rebalance charge them ? Running 5s 30c 8000mah

in this situation i would just balance in a low AMP, something like 0,5 AMP until the cells are all balanced. after this maybe put in storage mode and balance again, something like “reset” the battery.

below 3.7 you start to “kill” the battery. i never go below 3,75 with mine.

Not 3.2v

If your using a hobby charger you can just balance charge them to 4.2v

It won’t charge any higher. It stays right there

Is it a fake imax B6?

HTRC H120 AC 50W 70W / DC 100W x 2 Dual Ports 10A RC Balance Charger/Discharger for Lilon/LiPo/LiFe/LiHV/NiCd/NiMH Battery https://www.amazon.com/dp/B072JC1P13?ref=yo_pop_ma_swf

Hmm I’m not sure, clone imax b6s have this issue. Maybe they are using the same parts

Once I get home planning on discharge all til 3.7 and see if I can balance charge them back. It sucks too because I just got these batteries from HK about a week ago