EVE 280ah problem with 1 battery only?

[Alkaline]

Nothing its done you can not save it, it will just puff up and go to 0 volts like my grade B basen cells:

Basen EVE 280 Dead as a Doornail in 3 years.

Well in the back of my mind I knew it was only a matter of time, and now in less than 3 years the basen 280 EVE "Grade A" is dead. Checked the voltage and its 0 volts (or 0.012 v). Purchased from Alex Chen in Feb 2021... This was in a 8s battery back with an overkill solar BMS, the other cells...

diysolarforum.com

 

[GXMnow]

Yes I have checked all connections, no I have not changed the cell place I was thinking to do it but too much hassle I have already ordered a new one but I am trying to revive this battery for as long as the waiting time for the new one. Plus I am hoping it’s not a BMS problem. I will try to top balance them once more and see if it gets me through this week at least.

Yes I have tested with the multimeter every reading is exactly the same with BMS.

Did you measure the cell voltage on the bus bar or on the actual cell terminal or stud? It is very easy for a bus bar to make a bad connection to the aluminum terminals on these cells. You may need to sand the terminals and bus bars and reconnect it all with "No Al Ox" or come other aluminum corrosion inhibitor.

Adding to what @sunshine_eggo is saying, when you charge the battery back up, does the weak cell #14 charge up faster and hit high voltage sooner, or is it always low to the others? If the cell has low capacity, it will both charge and discharge faster. So if you top balance, the cells will still hit full together. The weak cell drops faster and becomes your usable capacity limit. But when you charge, it should then reach full along with the rest of the cells. But, if it charges slow, then the cell is either just way out of balance, or it has an internal short that is consuming power and making heat. A weak cell is less capacity, but still basically safe. A cell with an internal short is dangerous. Even LFP can over heat and blow it's vent if it is shorting inside.

A bad connection at the bus bar, would cause it to look like it is charging and discharging fast, just like high cell internal resistance. But the resistance is between the terminal and a bus bar. A bad connection can be fixed, a dying cell can only be replaced.

I also had a balance lead fail on my JK BMS. It caused it to report 2 cells as zero volts. I doubt this is your problem with the meter reading the same as the BMS, but it shows how a tiny bit of oxide can block current flow.

 

[xristostsilis]

So I completely replaced the cell and my battery has been running well since then. It was definitely not loose connection or wrong measurement (terminal or bus bar). The cell was bad which is weird.

 

[Alkaline]

Its not weird when cells have some internal problem like a short they don't hold voltage, swell up, or other bad things. Not much you can do about it. Grade A a lot less likely to happen but still is susceptible to this.

 

[xristostsilis]

Its not weird when cells have some internal problem like a short they don't hold voltage, swell up, or other bad things. Not much you can do about it. Grade A a lot less likely to happen but still is susceptible to this.

yes mine were grade b from docan.. ughh its ok i just got a grade a cell from nkon and it now works like a charm

 

[sunshine_eggo]

Its not weird when cells have some internal problem like a short they don't hold voltage, swell up, or other bad things. Not much you can do about it. Grade A a lot less likely to happen but still is susceptible to this.

+1

It's not common, but it's far from weird. I would say it's probably the #1 way cells fail. It certainly accounts for 100% of the failures I've had with lithium cells

 

[GXMnow]

Glad you got it fixed.

The possible issues, tests, and checks we offered here were mostly to narrow down and verify the issue. We mostly agreed it looked like a failed cell, but it is always best to be able to pin it down before spending the money, and then finding that was not the issue.