Balancing some new Eve 280 cells on 12th day question.

Zwy said:

Charging in parallel to 3.60V will take some time. I have some extra BMS's laying around (2 12V and 1 24V) and will charge groups of cells using those BMS's until there is a high cell voltage disconnect at the 3.60V to 3.65V area. I then parallel charge all the cells to top balance at 3.65V. Really speeds up the process.

If you have the time and don't need cells top balanced as fast, just keep doing what you're doing, you will get there.

Do you have the positive lead on one end of the pack and the negative on the opposite end? This will ensure more even charging for the whole pack. Considering you have cells at one end higher voltage than the opposite end, it appears you might have both leads on the same end of the pack.

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Horsefly said:

That power supply says 3.78V. I hope that is wrong.

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Horsefly said:

That power supply says 3.78V. I hope that is wrong.

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Schweg2 said:

Voltmeter says 3.60 v where the leads attach to pack.

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time2roll said:

Look closer at the bus bars. Some look tilted up on the insulation. I assume the voltage delta is from less than perfect connections

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Schweg2 said:

Voltmeter says 3.60 v where the leads attach to pack.

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Bob B said:

That could be affected by voltage drop at the power supply connection points .... as the current drops off, that voltage drop will decrease .... the voltage will be too high.

Best is to set the voltage with DVM connected to power supply leads but not the battery .... Then connect to the battery and don't adjust any more.

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Zwy said:

You need to set the power supply to 3.65V or lower unless you want cells that are ruined.

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Ellcon123 said:

More importantly you need to set power supply to 3.65V before connecting to batteries. Just to clarify.

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