According to the wise words of Mooch:
“Salt water discharging is incredibly slow and causes electrolysis destruction of the tabs, exposing the inside of the cells and creating toxic sludge water”
I recommend you fined proper places to do research sutch as manufactures instructions or recycling businesses. Just because people say carrots help you see in the dark, eating crusts make you hair curly doesn’t make it true. Disharging lipos below there safe limit is dangerus and toxic.
That said, you know the use case for your battery better than we do. Sometimes its the best idea to wrap every single square inch of a battery in fish paper. Sometimes thats either not possible, or not necessary. It all depends.
Here’s a battery I am building for a customer right now:
Notice how the only fish paper are the rings on the positive terminal, the strips under the positive nickel fold, and the strips between the sides of the p-groups?
Normally I would wrap the entire p-group all the way around, but that is actually not possible on this pack, as the space in each enclosure segment is wide enough for 8 21700’s, one layer of fish paper, and literally nothing else. Adding one layer of kapton all the way around each group nearly made the battery not fit.
Though in addition to it not fitting, I also deemed a full fish paper wrap unnecessary, as with so little space in the enclosure and each section of the battery being total isolated by the enclosure, the chances os something conductive getting where it shouldnt are slim to none.
So it really all comes down to your application.
To answer your question simply,
A bit of kapton almost never hurts anything, and fish paper is even better
To be clear, I wasn’t advocating that people use the salt water method to fully discharge lipo batteries.
Also rather than answering my original question, you instead imply that I didn’t do any research. Just in case I made a mistake, I did another round of research. Everything that I am finding online says that lipo batteries (not lithium-ion) should be fully discharged to 0 volts prior to recycling.
Clearance isn’t an issue at all for my current build right now luckily, and I don’t ever intend on riding it in the rain. But since I did my s-connections with 12awg so there are solder balls on each p-group and I wasn’t sure how I could get kapton tape or fish paper on there and make it stick. I think I have a better idea of how to now though
My favorite method for this is to put down a layer of kapton over the nickel, then cut a square with an x-acto knife and solder in that square, then tape over that
If done carefully and properly that shouldn’t be an issue. But…
Salt water discharging can dissolve the tabs before the cells are discharged, leaving them in a condition that could cause the very problems the discharging was supposed to address. If the LiPo’s are handled like they are inert, instead of partially charged, then that could lead to them being short-circuited.
If the tabs fully dissolve In the salt water, and the internals of the cells are exposed, then you have toxic organic solvents in the water which then get dumped down the drain. It’s a hazard to touch or breathe too.
If discharging to zero volts via a bulb or another method then bottom balancing needs to be done while (slowly!) discharging in order to prevent one or more cells from dropping below zero volts. If this happens it’s the same as those cells being charged with reverse polarity and that’s a great way to start a fire.
Depending on their voltage the amount of energy available to create a fire could be very low but this is not a risk-free procedure.
I am not saying that discharging LiPo’s before disposal is “dangerous”. It’s just not a trouble-free, no-worry thing to do in order to make the pack “safe”. This has to be balanced against just wrapping the pack up to prevent short-circuits and recycling via a dedicated battery recycling bin.
Millions and millions of LiPo’s are disposed of every year without being discharged first. For large packs though that contain huge amounts of energy it could help to get rid of some of that energy first (zero volts is not needed) but the risks should be considered when choosing how.
Dang man, it feels like you are trying to start a fight. I stated above that I am not advocating for the use of the salt water method. I’ve personally only used the light bulb method.
The electrical misusage criteria above is applicable for maximizing the lifespan of the battery, not for how to prep a battery for recycling.
The intent behind prep’ing a lipo to 0 volts is to prevent the battery from starting a fire if the cells get ruptured during the handling, transporting or recycling process. It also protects the battery from shorting out against another battery. Yes I know, you are supposed to insulate the exposed terminals prior to recycling, but not everyone is responsible enough to do that.
I do brake down larger packs I built in to separate cells then tape them up with pvc tape then drop them off to some were that sells battery’s
(it’s law in the uk that any selling battery’s has to take battery’s back for recycaling most places will try to avoid taking them as thay have to pay for disposal but supermarkets don’t motor it so I just drop them in there battery bin when I do a shop.
To be fair monsterbuilder specifically said lipo (not lithium ion) to he discharged in water. Than you show him a 18650 30q chart and tell himhe should have looked their first.
[quote=“monsterbuilder, post:11628, topic:720”]
Everything that I am finding online says that lipo batteries (not lithium-ion) should be fully discharged to 0 volts prior to recycling.
[/quote
He never disclosed what manufacture or model. So i went with the most commonly used manufacture and model batery used on this forum.
Never provided any sources of information let alone creditable ones. Just spouted hearsay and wives tales misinformation. What he dose is dangers according to every manufacture and sellers information iv seen for health and safety reasons.
Saying I done it for years with out issue can lead others to follow suit and might not be so lucky. We seen enough fires and destruction as a community should be advocating for better procedures as technology and knowledge improved.
Over discharging is old method when we had acid and ni cd battery’s that we’re stable at 0V to avoid fires in garbage compactors. We’re now we dispose of them separately. Well at lest should be