The cell is now contaminated with aluminum shavings and moisture and will fail. The liquid is a blend of ethylene carbonate, dimethyl carbonate, vinylene carbonate and LiPF6 salt.
As someone who had a pleasure of doing some very water sensitive chemistry in past life I say not necessarily.
First, the OP reports the gooey layer beneath. This may very well be some rubber that provided sealing and didn't allow water vapour ingress into the cell. If this is the case and the Op hasnt introduced any water containing stuff in there that could slowly diffuse (like grease that contains water) it may be fine.
Also for anyone that wants to repeat this. It may be a good idea to use grease with guaranteed no water content. For example Dow Corning High Vacuum Grease - not ideal for milling anything, but it will catch chips and definitely does not contain even a trace of water.
Then the hole should be closed ASAP. Definitely not left open for minutes (or even worse hours or overnight). Really OCD people may want to flow argon slowly around and into it while taping and before closing up.
IDK if thread locker is guaranteed to be water free. I'd probably prefer not to use it relying on the leftover grease for sealing the threads.
This way one can prevent Ingress of enough water vapour to cause problems most likely.
A lot of people don't know how much force is actually applied with as "little" as 6nm.
Also torque wrenches are really inprecise instruments. I set my to 5Nm just in case.
Weight isn't that much of an issue for a 'house bank' (it is a factor in mobile applications like motorhomes, caravans and EVs obviously), and the heat toleration of LYP versus LFP makes it the far better choice for my local conditions (where summer temps can be weeks on end of 40-45C plus, and sometimes even much higher...) LFP really suffers under those conditions, with charge throttling required, and it shortening their service life (by a considerable margin...)
Wow, I didn't know these LYP cells even existed. They are very cool. I think they deserve to be more popular.
Has anyone explored TIG welding, even tacking, broken terminals? Heat control
Right, and this is why microTIG machines exist, I suppose - they heat a nearly microscopic area -
Micro tig only works well on alloys that can be welded with DC.
Aluminum can be DC welded with helium.
However, having some experience tig welding aluminium (including tiny stuff in a magnesium-aluminium and aluminium alloys) I'd not do it. There is a reason they use a laser and not Tig/Mig. That reason is less overall heating. The problem with aluminium is you need to blast it with enough current to remove oxides and also it is excellent heat conductor. With tiny parts the biggest danger is: "it's not puddling, it's not puddling, oh shit, the whole thing has melted! ". There is an extremely fine balance between "it's not puddling" and "crap, the entire thing has melted". In my opinion a tig torch is simply not concentrated enough(up to 300hz I tried at least). That whole piece would get pretty hot. Drilling and tapping is the correct method (unless one has a laser welder).
That looks like a good weld, why are a lot of the ones we see looking cracked?
We can't really tell without seeing a cross section or at least the bottom as well as the top.
You need to find a guy like this:
see if he can attach them back
Making boxes like these is one of the most satisfying ways to "get into" tig welding aluminium. It is 99% material prep(and having something to lean your hand on, and do the movement without switching the torch on first) . It is not that difficult... Welding good looking corner joints is a very different skill than making small structural welds.
