Some corrosion on one of my new cells vent, should be ok?

[brandonboosted]

The vendor says it will be ok but wanted some other options, I’m sure it’s just water got in there but I can’t find any information on it. Thanks

 

[sunshine_eggo]

Picture is blurry (QR Code is out of focus). I can't tell what you're talking about.

 

[brandonboosted]

Picture is blurry (QR Code is out of focus). I can't tell what you're talking about.

I will try to get a better pic later sorry.

 

[brandonboosted]

Unfortunately these cells also are under capacity, ugh thought I finally found a reliable supplier.

 

[SparkyJJO]

What are they measuring at? What supplier?

 

[brandonboosted]

First of 12 measured 274ah, going to wait on supplier to see how they handle it. I will say a known usa supplier.

 

[SparkyJJO]

What temperature did you run the test at? That's only 2.1% off. Thermals could play at it. Also if they're not automotive grade the odds of them being slightly off are higher.

I'd bet if I capacity tested my 230Ah cells that I would have some measure a hair lower than 230.

Not sure about the discoloration on the vent though.

 

[brandonboosted]

71F same as I tested my other grade a 280Ks that are 6 month old and all pulled full capacity again after sitting 6 mo.

 

[sunshine_eggo]

All 9 of my Eve cells from Amy L tested under spec. Regardless of who is saying what, nobody is getting true Grade A cells.

If there's no actual liquid in the vent, I'd say it's good.

 

[brandonboosted]

All 9 of my Eve cells from Amy L tested under spec. Regardless of who is saying what, nobody is getting true Grade A cells.

If there's no actual liquid in the vent, I'd say it's good.

There is a lot of talk right now about these cells and capacity. Word is all these cells are under by a small margin, hopefully they hold that same amount as long as they are suppose to and we aren't seeing some quick acting degradation.

 

[sunshine_eggo]

There is a lot of talk right now about these cells and capacity. Word is all these cells are under by a small margin, hopefully they hold that same amount as long as they are suppose to and we aren't seeing some quick acting degradation.

I think that conversation has been going on for the better part of the life of this forum.

Received in Jan/2021, 8 of 9 of my cells were essentially perfect, low IR, extremely low self-discharge, etc. They just fell short of capacity coming in around 262-279Ah. The 9th one was an outlier in self-discharge, which is the worst one when considering maintaining a top balance - it discharged about 5X faster than the others, but still WELL under the cell specification.

 

[brandonboosted]

I think that conversation has been going on for the better part of the life of this forum.

Received in Jan/2021, 8 of 9 of my cells were essentially perfect, low IR, extremely low self-discharge, etc. They just fell short of capacity coming in around 262-279Ah. The 9th one was an outlier in self-discharge, which is the worst one when considering maintaining a top balance - it discharged about 5X faster than the others, but still WELL under the cell specification.

How do you test the low discharge? just leave them and test them weeks or so later?

 

[sunshine_eggo]

How do you test the low discharge? just leave them and test them weeks or so later?

Yep. 5 months.

 

[brandonboosted]

Yep. 5 months.

How much is considered normal and what was your results?

 

[John Frum]

Does anyone actually see any corrosion?

 

[sunshine_eggo]

I'm assuming this:

 

[John Frum]

I'm assuming this:

View attachment 106426

But is it corrosion though?

 

[sunshine_eggo]

But is it corrosion though?

Maybe. It breaks the Sesame Street rule... "one of these things is not like the other."

 

[Tim Tim]

But is it corrosion though?

To me it looks like some of the liquid has condensed under the seal or that there was a small amount there that has since evaporated.