AdriftAtlas
New Member
I bought four Eco-Worthy 12.8V 150Ah (165Ah) Metal BT batteries. Three of them only diverge more than 10mv at less than 10% SoC, all manufactured Sep 26th. However, one of them manufactured Oct 30 begins to diverge by 15mv at 30%, 30mv at 15%, 43mv at 10%, 86mv at 7%. The biggest culprit appears to be cell 2.
I've let the BMS top balance the cells several times and they're within 10mv when the pack is 14.5V. I've cycled it several times and it always the same. I did a capacity test on it using a Victron Shunt and it counted 163Ah before cell undervolt at 2.5V. So it's close to 165Ah that the BMS reports, and 13Ah more than advertised on the tin.
However, I'm concerned that there is something wrong with the cell. I'm going to put these four batteries in series for a 51.2V nominal pack, so I really don't want one battery to fail on me.
What is going on here? Will it degrade faster or potentially cause early pack failure down the line? Do I request an exchange?
Pictures Attached.
I've let the BMS top balance the cells several times and they're within 10mv when the pack is 14.5V. I've cycled it several times and it always the same. I did a capacity test on it using a Victron Shunt and it counted 163Ah before cell undervolt at 2.5V. So it's close to 165Ah that the BMS reports, and 13Ah more than advertised on the tin.
However, I'm concerned that there is something wrong with the cell. I'm going to put these four batteries in series for a 51.2V nominal pack, so I really don't want one battery to fail on me.
What is going on here? Will it degrade faster or potentially cause early pack failure down the line? Do I request an exchange?
Pictures Attached.
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