exactly, thank you.
im so done with this thread
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Yeah because endless sphere is a great source
“Splash proof enclosures are a bad idea because the sun hits the top, causing them to fail, so drilling a hole in them to let the water out is a good idea”
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THIS. SO MUCH THIS.
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lol
asses
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Like the one i cant shit out of 
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Your messages can literally kill humans. I’m no fan of censorship, but continuing to give out dangerous advice is reckless at best and malicious at worst.
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A S S E S S
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The water that damaged the BMS could have also shorted out P-groups, which could have brought their voltage down below safe minimums, which can start dissolving the anode in the electrolyte inside the cells. Forcing a charge into the battery around the BMS could then cover up this state, and you wouldn’t have much of a way to tell if you’ve damaged any of your electrode material. Using those cells afterwards in that state could be extremely dangerous.
Prior to the P-groups being charged, they could have simply been measured to assure they were all above 2.5V, but it’s now too late.
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Post has been deleted by author
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Pathetic. I guess too dangerous to talk about even assessing water damage here.
I keep getting tagged for a thread I don’t want to deal with. 
In my humble personal opinion this thread is mixing together, badly, technical realities and what we feel should and shouldn’t be done when dealing generically with this situation. These things need to be kept separate when discussing situations like this.
I get it…we can’t take a ton of time trying to dig out all the details, which may never be known, so safe “best practices” are the thing we can easily fall back on.
But we need to be careful. Taking the time to separate out what each person is and isn’t really saying, completely independent from how we personally feel about a situation, is important.
Is it possible to assess if a pack (or individual cells) has been damaged by water? Of course it is possible…depending. Saying it would be impossible for every possible type and degree of water exposure makes no sense and I’m hoping no one is saying that.
How easy it is to assess possible damage? That depends on a lot of things too.
If there is no visible damage (other than, let’s say, water-damaged fishpaper) then some careful testing of the pack needs to be done. Water can’t short-circuit a pack but it can fry the BMS and that could leave the pack open to being short-circuited by something else or damaged by the BMS (“balanced” until zero volts e.g.).
Water also can’t mix with anything inside of a cell unless the cell has popped its venting disk or the cell has burst. At which point it’s obvious that the cell is gone and the water doesn’t matter (nothing in the cell can react with the water).
Since this electrical testing of a pack is not an easy thing to do it’s just a whole lot easier to recommend replacing the pack and that’s what I would do if I had to give advice on what to do. We have to say that, we don’t know what’s going on with the cells in the pack.
But there’s a good chance that testing of the cell voltages, the pack’s internal resistance, capacity, and response under load could determine if the cells are damaged.
If the pack was damaged and then charged then we might have lost the opportunity to check if particular cells were shorted. But if the pack wasn’t balanced then discharging the cells slowly back down would reveal whatever voltage imbalance there was before.
But that’s just not needed…
Cell damage doesn’t disappear if the pack is charged. Any damage will still affect the capacity, IR, or performance of the pack. Not knowing the cell voltages after the water exposure, and before anything was done to the pack, makes it harder to determine if the pack was damaged but it doesn’t make it impossible to do. It just makes it too impractical for most people to deal with when a new pack can just be bought.
And so this would lead to my recommending that the pack would be replaced. If the cells voltages were an obvious disaster (under 2.0V for example) then we’d know that damage was possible…replace the pack. If the cells were all still pretty well balanced and above the 2.5V rating after water exposure then they’re probably okay but we can’t know for sure.
If it was my pack, I might just carefully charge it and see what happens. If it was someone else’s pack then, absolutely, I’d recommend replacing the pack. To do otherwise would be irresponsible.
So, bottom line…yes, we might be able to properly determine if any cells were damaged but that is not easy to do. What is easy is to err on the side of safety and recommend replacing the pack.
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College student living in a dorm without the right tools to open, then reshrink the pack = instant no-no.
Not to mention it’s impossible to source the BMS the manufacturer uses, and there isn’t enough space for something off the shelf .
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pretty easy to spot.
Makes no real practical difference but…anode. 
It’s the anode’s copper foil that possibly dissolves (for certain cells, we don’t know which) when the cell is at a low enough voltage for a long enough time and then plates out of the electrolyte when the cell is recharged.
A real dangerous and under appreciated issue IMHO. Not a real prevalent one since so many people “recover” or “revive” zero voltage cells but some do catch fire and that’s just not something we consider to be a good thing to happen to an esk8 pack. We have to fall back on our best practices and not play the odds.
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Completely agree. Each circumstance (doesn’t have to be this one, just speaking generically) needs to be looked at individually.
But this is just our best practices fallback. There can be students who can do this as safely as any of us. We just have to assume that there are some who won’t do it well so we must say don’t do it. Especially if we know what tools and experience they have and we find that it’s not enough.
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No one’s looking at any circumstances here and instead saying don’t look at it, don’t assess if it’s possibly been damaged and just throw it away. I’m fine arguing about this and I know the reality.
You’re completely missing the bigger picture. College student asks if there’s anything he can do. The answer is basically no, there’s nothing he can do safely with the tools at his disposal. You show up, telling him that there are things that he can do which just aren’t safe given the circumstances. That’s why you’re getting flagged to oblivion.
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I was speaking generically, just about any situation that fits his description. I was not talking about this particular situation. I will update my post.
I think we’re all on short reaction leashes here, all taking things very personally. It just doesn’t have to happen, I’m grabbing a coffee and some great dark chocolate and watching some spectacularly silly show.
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Measuring cell voltages at the balancing connector wasn’t an option (I haven’t read all the posts)?
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The pack had already been charged (around the BMS) before this could be done.
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