Visual Inspection - Are these cells bad?

[0verk1ll]

Hey everyone,

I removed the battery cells from my camper yesterday as I was rearranging things and noticed one was bulging and appeared to be leaking on the bottom. The others don't appear to be actively leaking but I can see some ripples and peeling around the bottom that I'm concerned about. I was curious if someone with more experience/knowledge can look at these and tell me if they're ok to keep using or I need to toss them.

These are 120ah cells I got off Aliexpress in 2020. I can't remember the seller but they had good feedback and reviews at the time. I had Gorilla tape around the bottom edges as padding, which you'll see in the photos and is why you'll see some of that residue as well as some of the black liner pulled off. Yeah, I know I should have used something else but I was on the road and just winged it :/

Here's the bad one.




Here are the others that I'm concerned about. Do I need to replace the whole lot or do these look ok? I believe the mark on the blue side of the second photo is from some rubbing before I put the tape on, not a leak.


Thanks for the input.

 

[Quattrohead]

I would scrap the whole lot and start again, they look like zinc carbon batteries leaking LOL

 

[justgary]

It looks to me like they got wet and maybe hot.

Do they still work? If they still seem to hold a charge OK, I would unwrap them (remove the blue wrap) and carefully clean them, dry them, then wrap them again with Kapton tape. Note that the aluminum outside case is connected to the positive electrode, and should not come into contact with other cells while it is exposed.

When you reassemble them, use a compression frame with decent insulation (e.g. FR4 PC board material) that will ensure that the cells cannot rub against each other and create a short.

 

[Brett V]

just from the photos supplied, it looks like corrosion on the outside of the aluminum from moisture getting under the insulation sleeve. It's hard to say if the aluminum case has been compromised, and if not, how close it is to being there. Being used in an enclosed space, I wouldn't trust them.

 

[0verk1ll]

Thanks for the input. They do still work and I wouldn't have noticed anything if I hadn't taken them out and looked at them. I don't know how they could have gotten wet, given their location, but I guess anything is possible. They definitely could have gotten hot, but shouldn't have been anything too extreme.

I guess I could remove the wrapping and see if I can tell if the aluminum casing is compromised and go from there. I'll have a look and report back.
Obviously I don't want to cause bigger issues by putting defecting ones back in, but also don't want to have to spend more cash (this is part of a bigger project). Also, right now I'm having a hard time finding cells that are this size and will fit in the required location from trusted suppliers. Seems Docan is the only one.

 

[Alkaline]

You guys need to be putting them in some type of case instead of using duct tape like some ghetto seat belt to keep them in place. At least a minimum plywood with bolts and clamps.

 

[0verk1ll]

You guys need to be putting them in some type of case instead of using duct tape like ghetto seat belt to keep them in place. At least a minimum plywood with bolts and clamps.

The tape wasn't to clamp them together, it was to put more protection around the bottom edges. I was on the road, in another country, and just trying to make something work. Also, there is no room in this location for clamps, bolts, etc., so it requires being a little "ghetto". Thanks for the input.

 

[0verk1ll]

One question: Does anyone know a reputable shop where I can buy individual 120AH cells? Particularly ones that don't have 2-3 month shipping times?

Regardless of the condition of the remaining cells, I know I have one that's bad and I'm scared to put it back in. I'm not sure what all the dangers are with that, but seems like it's not worth it. Unfortunately, I'm having a hard time finding anywhere I can order 1 or 2 cells of the same kind. Docan has them but only in full sets. Any ideas?

 

[chrisski]

Regardless of the condition of the remaining cells, I know I have one that's bad and I'm scared to put it back in. I'm not sure what all the dangers are with that, but seems like it's not worth it

What is wrong with this cell?

 

[0verk1ll]

What is wrong with this cell?

The bad one is leaking. There's a photo of it in the original post. I did pull back the blue lining since then and I can see a crack in the aluminum and I can definitely smell the fumes. I can get a photo of the leak in a bit.

 

[0verk1ll]

Here's the bad cell. You can see where the aluminum is compromised.

 

[justgary]

Was it sitting on pressure treated wood? It looks like it got wet and the copper from treated wood leached up and corroded the aluminum.

 

[0verk1ll]

Nope, it was just sitting on a polyester mat. There *shouldn't* have been any contact with anything but that. I'm also confused as to what could have gotten it wet, since it's not generally a place where water would get. But, then again, it's in a battery compartment with no drain so if anything got in there then it wouldn't have anywhere to go. Either way, that cell is hosed now and I haven't found a replacement.

 

[RCinFLA]

Internal electrolyte will not corrode case. Something external did that. Salt or chlorine bleach is the most common cause.

I have heard from others that pressure treated wood preservative will corrode the cases.

 

[justgary]

Nope, it was just sitting on a polyester mat. There *shouldn't* have been any contact with anything but that. I'm also confused as to what could have gotten it wet, since it's not generally a place where water would get. But, then again, it's in a battery compartment with no drain so if anything got in there then it wouldn't have anywhere to go. Either way, that cell is hosed now and I haven't found a replacement.

You might try a warranty claim with the manufacturer if you want to have some fun. The aluminum case could have been bad, or maybe something got between the case and the blue wrap. As long as you treat it like a cat-and-mouse game with no expectations except wasted time, you could enjoy trying to get satisfaction.

 

[Solar Guppy]

100 Ah batteries prices have really nose dived in prices recently, why even bother building one when your can just have a new one in 2 days all sealed?

Examples:

$208 ( 13.85 x 6.85 x 7.48 )
$209 ( 10.2 x 6.6 x 8.4 ) Mini
$210 ( 12.6 x 6.3 x 7.87 )
$220 ( 10.2 x 6.6 x 8.2 ) Mini with $60 coupon

 

[0verk1ll]

100 Ah batteries prices have really nose dived in prices recently, why even bother building one when your can just have a new one in 2 days all sealed?

Examples:

$208 ( 13.85 x 6.85 x 7.48 )
$209 ( 10.2 x 6.6 x 8.4 ) Mini
$210 ( 12.6 x 6.3 x 7.87 )
$220 ( 10.2 x 6.6 x 8.2 ) Mini with $60 coupon

Unfortunately all of those are too tall for the space. I've only got about 175mm in height to deal with, which is why I'm really limited in which individual cells I can put in there. I heard back from IMR batteries this morning and they have some in stock that I can get in a few days. The only potential problem is they have laser welded studs in there that may make it too tall, but I can always trim them down if needed.

As far as warranty on the old ones, I doubt I'd be able to get anything, but yeah it could be fun to try. I'd have to dig up which seller I even got them from and see if they're still around.

And for the corrosion, I don't see how anything other than normal fresh water could have gotten down there, or carbonated water actually. A few weeks ago while working on the van my nephew knocked over a can of seltzer and it's possible some got down in that compartment. Otherwise, that area is pretty isolated and wouldn't really accumulate incidental water/moisture.

Either way, I may just order a cell from IMR and be done with it. I did have one more minor concern about one of the cells if I could have someone weigh in on it. One of the others that I pulled back the lining from had this weird spot on it and I couldn't tell if it was a leak, corrosion, or what. I cleaned it off and it appears the casing may be slightly pitted but I can't see or smell a leak. Does this look normal or would you suspect a leak?

 

[Solar Guppy]

Out of curiosity, what is the area size you have the cells in now? the 10.2 x 6.6 x 8.4 could fit if on its side? ( 6.6" is 153 mm )

 

[0verk1ll]

Out of curiosity, what is the area size you have the cells in now? the 10.2 x 6.6 x 8.4 could fit if on its side? ( 6.6" is 153 mm )

I believe the specific measurements of the compartment are: 11.75 x 6.75 x 6.75.

I started to wonder about side mounting as well but the bottom footprint of the compartment isn't any bigger. There is more clearance as it goes up from the floor, but the bottom is still only 6.75in. It's a 1987 Vanagon - I guess they didn't ever imagine people putting very big batteries in the aux battery compartment. Hell, even most lead acid batteries won't fit in that compartment. It's really a limiting space.


I may be able to fit one of those mini 100ah batteries in a different location without giving up valuable storage space, but I'm gonna have to do some more measuring/brainstorming.