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Rust on battery pack

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Hank42

Legacy Supporter
Sep 30, 2012
699
531
United States - NY
I've noticed a litle rust on my 2012 battery pack a few years ago and mentioned it to the SC. "It's normal", they said "not a concern".
Today I heard a flapping noise and looked under the card to see the glued-on black plastic was dangling off the sides of the battery- apparently the glue is sticking to the metal, but the metal rusted through/off.
PLASTICCOVERBATTERY_123148.jpg

Ironically, the rest of the battery pack is not rusting, just the perforated rails that run from front to back on each side of the battery under the car.
UNDERBODYBATTERY_123020.jpg
UNDERBODYBATTERY_123030.jpg


Anyone else see this issue?
I'm thinking of sandblasting the metal and painting it. but it looks like it's just going to rust through again - looks like water gets in through the perforations above and it rusts through from the top.
 
I was under the impression the packs were aluminum...

Is that not the case? And if it is, is this some sort of galvanic corrosion?
No, the packs are steel. Not sure why just the areas covered by the black plastic is rusting and the rest of the pack is in perfect shape. Almost as if these pieces (which are welded on) are of a different steel - not even sure what the purpose is.
 
No, the packs are steel. Not sure why just the areas covered by the black plastic is rusting and the rest of the pack is in perfect shape. Almost as if these pieces (which are welded on) are of a different steel - not even sure what the purpose is.

Maybe yours is, but mine doesn't appear to be. At least my magnet doesn't believe so.

My magnet does believe the material under the plastic cowling is ferrous, however. But that appears to be part of the vehicle, and not the pack.

The fact that portion of the vehicle is subject to that kind of rust is worrisome. It almost makes me wonder if that car didn't get the dip/coating correctly....
 
Maybe yours is, but mine doesn't appear to be. At least my magnet doesn't believe so.

My magnet does believe the material under the plastic cowling is ferrous, however. But that appears to be part of the vehicle, and not the pack.

The fact that portion of the vehicle is subject to that kind of rust is worrisome. It almost makes me wonder if that car didn't get the dip/coating correctly....
That's just the thing - every other part of the car (that is steel) is fine. There's no corrosion, or oxidation on the aluminium parts either, just these two "Rails" or whatever they are [ I removed some plastic panels to take a peek]. Maybe this is an undocumented "Sacrificial Anode" :)
 
I believe the side rails are steel (coated with plastic) and the rest of the case is thick aluminum
you could put some ospho on the rust part and it will at least turn the oxidized parts black

I don't think that any rust on these rails will have any bad effect on the pack. Pretty sure the rails are just extra protection. The are the points that hit the ground over big speed bumps or steep driveways
 
I believe the side rails are steel (coated with plastic) and the rest of the case is thick aluminum

If you look at the pack construction, and how the bottom is welded to the sides, I don't think this is likely. Teardown pics appear to indicate this is all aluminum.

I think the perforated steel rails you are referring to are part of the car, not the pack.
 
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