It was a while back when I bought some cells from Aliexpress, found problems straight away, despite much testing and proof that there was some faulty cells they still refused to admit it.
Not going to go into details about all of it now as I'm done with all that.
I will just show what was going on and why, the cell would show voltage but would not discharge the voltage would drop to zero (open circuit) when connecting the inverter.
I removed the cell and tried to charge it separately from the others, it would take current for a moment then go open circuit, put a lot of weight on the terminal and it would start again.
I only recently got hold of a little endoscope camera so I thought I would check inside the cell
Sorry about the small photos, the camera was only 640X480 and had a agle mirror on the end made it worse.
The square aluminium block is the battery terminal going through the plastic top, photos are upside down.
The little plate should be holding the battery plate to the terminal, not sitting there on holiday.
You can see the plates are barely touching the terminal, any wonder it don't F
n work.
Hey there's a washer!!!
Oh look, a NUT FFS.
The terminal at the other end with copper plates, can see some threaded rod.
The rest of the cells are working ever since after replacing 3 that were like this.
Well I learned my lesson, don't buy cells from Ali.
I have these batteries in the shed running most days and sometimes they power the house, so I'm getting use out of them.
They are getting out of balance more often lately so will have to make some changes, more on that later.
Cheers Aaron
Off The Grid