SMC Battery Dead Cell?

[ZooKeeper]

I noticed this when I went to charge the battery, cell #1 doesn't show on my charger. I decided to check it with another device and still have the same results, no #1 cell.

I've checked what I can of the wiring on the balance lead, there are no issues with the connector/pins. If I gently tug on the balance leads to the inside of the battery nothing is loose. If I wiggle the balance leads on the battery side trying to check for a short, cell #1 never pops up on the lipo checker.

Should I assume this battery is toast at this point? Per my notes, I started using it November 2020.

 

[ChemEng]

Its not reading zero... its reading "open" so it seems like the wire is broken off the tab inside the battery. What is the voltage at the main lead? is it 19V or 22.8V?

It almost doesn't matter, without that lead you can't balance charge, so unless you are VERY brave and VERY good at soldering then you shouldn't try to fix it. Get the butter out, that battery is toast.

 

[Hector_Fisher]

I have two 3s of the same battery (extreme V2s). Had to retire them since one cell on each battery has crazy high IR and the hard cases are getting a little puffy.

Something is definitely not right for your battery since the "total" voltage your checker is reading is 19v. That's equivllent to 5 cells at 3.8v per cell. I would not use that lipo anymore.

 

[ChemEng]

I have two 3s of the same battery (extreme V2s). Had to retire them since one cell on each battery has crazy high IR and the hard cases are getting a little puffy.

Something is definitely not right for your battery since the "total" voltage your checker is reading is 19v. That's equivllent to 5 cells at 3.8v per cell. I would not use that lipo anymore.

That 19V is just the sum of the balance leads (3.8 x 5) it doesn't measure the main lead...

you can measure the main lead with a volt meter (or your charger) if the main lead is 19V then you have a dead cell... if the main lead is ~22.8V then the 1st cell is still good, just disconnected from its balance lead.

 

[Hector_Fisher]

That 19V is just the sum of the balance leads (3.8 x 5) it doesn't measure the main lead...

you can measure the main lead with a volt meter (or your charger) if the main lead is 19V then you have a dead cell... if the main lead is ~22.8V then the 1st cell is still good, just disconnected from its balance lead.

Good call. Had i been actually looking more closely at the picture I would have noticed that
Most likely, as @ChemEng stated, it's the balance lead internally disconnected then. Since, if it was the actual cell 1 main tab, i wouldn't suspect you'd be able to use the battery period.

 

[ZooKeeper]

Thanks for the feedback @ChemEng & @Hector_Fisher, I didn't even think to check the main lead and do the math. I've just checked it now and it does read 19v. That being said, I agree that cell #1 is dead. I'll do a full discharge to 0v on this battery and put it in my battery disposal pile.

 

[Rocketzx1]

That 19V is just the sum of the balance leads (3.8 x 5) it doesn't measure the main lead...

you can measure the main lead with a volt meter (or your charger) if the main lead is 19V then you have a dead cell... if the main lead is ~22.8V then the 1st cell is still good, just disconnected from its balance lead.

This information just helped me in proving my SMC HCL-HP pack does indeed have a dead cell. This is very good information to kno, thanks for sharing!