PSA Disposing of old lipos in salt water

[Slick2500]

Stop doing it.

https://forum.flitetest.com/index.p...o-disposal-bad-idea-or-really-bad-idea.12467/

https://www.reddit.com/r/fpv/comments/12vmh26/read_about_killing_a_lipo_by_putting_in_in_salty

https://rcbattery.com/safe-disposal...SAz6Usev17KHGucGYudkcP6tnGsV8e7NZGjR-j3FyK3MJ

 

[olds97_lss]

https://forum.flitetest.com/index.p...o-disposal-bad-idea-or-really-bad-idea.12467/

So, what is the safest way to dispose of LiPos? Enter the humble incandescent 12 volt automobile taillight bulb. If you have any skill at all at soldering (and you'll need it anyway if you do anything with electric RC) it's very easy to solder some wire to the contacts of a 12 volt automobile taillight, add whatever your battery connector of choice is to the other end and insulate it with electric tape or heat shrink. To dispose of your battery, just plug the battery into the taillight, put it somewhere where it's safe (I use the holes in a cinderblock with a plastic baggie full of sand above - if the battery blows the baggie will melt and the sand will pour over the battery) and leave it until the bulb goes out. Then leave it for some hours more, check the voltage to make sure the battery is completely discharged, cut of the battery connector, strip the wires and twist them together. Then dispose or recycle the now completely safe battery. A single taillight bulb will work for up to a 3S pack of any size, use two taillights in series for 4S or more.

Kind of amusing... I've been doing it that way since I started running electric, well, minus the cinderblock and sand. I use a metal can with fireproof gloves over it and sit in the room until they are discharged. I also use 4 or 5 50W 24V halogen bulbs wired in parallel as the discharge load so I can discharge 2s-6s, although, I do use an actual discharger to take them down to 3.2V first. 250W of light at nearly 25V on a 6S pack is really bright! I used to solder the wires together after discharge, but stopped and just leave them longer so they twist, then I tape it up so it doesn't untwist.

Never thought the salt would dissolve the tabs. I just didn't want to deal with a bucket of saturated saltwater. lol!

 

[Greywolf74]

I mean I get what they are saying, and it's true up to a point, but for the first 7-8 years I was in the hobby that's how I used to dispose of my lipos and none of them ever had more than maybe a volt or volt and a half after 2-3 weeks, so do they have a point? Yeah, kind of, but in all practicality, it's a non issue because the packs will get charged down low enough to dispose of before the corrosion presents a real issue. If you're worried, just check the leads with a multimeter before taking it out of the salt water and disposing of it. Also, if you happen to get unlucky enough to still have too much voltage for disposal, all you have to do is re-strip another 1/4 inch off of the leads, and you'll be good to go.

 

[Slick2500]

I mean I get what they are saying, and it's true up to a point, but for the first 7-8 years I was in the hobby that's how I used to dispose of my lipos and none of them ever had more than maybe a volt or volt and a half after 2-3 weeks, so do they have a point? Yeah, kind of, but in all practicality, it's a non issue because the packs will get charged down low enough to dispose of before the corrosion presents a real issue. If you're worried, just check the leads with a multimeter before taking it out of the salt water and disposing of it. Also, if you happen to get unlucky enough to still have too much voltage for disposal, all you have to do is re-strip another 1/4 inch off of the leads, and you'll be good to go.

Shouldn't they read zero for proper disposal though? The one time I tried it I left the battery in the bucket for 2 weeks or so and most of the wires had corroded off of the cells so stripping the leads back wouldn't have helped. The 2 cells I could still get a reading on were still showing over 2.0 volts. At the end of the day does using salt water work, sort of but here are much faster and cheaper ways to dispose of batteries and as @olds97_lss mentioned you don't have to wonder what to do with the bucket of waste.

 

[nino]

Poke it with a nail and it will discharge completely!

*Advice offered in this post should not be taken as advisable.

 

[Lukedavis]

I much prefer the method of chucking it up in the air onto the asphalt and then tying it to be dragged behind my friends Hoss! (It was a dumb idea. DO NOT try at home.)

Poke it with a nail and it will discharge completely!

*Advice offered in this post should not be taken as advisable.

 

[Lukedavis]

Poke it with a nail and it will discharge completely!

*Advice offered in this post should not be taken as advisable.

You could use it as target practice for a bb gun or real gun. (P.S. I'm putting this in here so I don't get sued when some dummy does it and causes a forest fire and he blames me for giving him the idea)

 

[Doom!]

You should save all of your old lipos, strap them to a vest and walk into a bank to make a withdrawal.

 

[Greywolf74]

Shouldn't they read zero for proper disposal though?

Not trying to be a stickler/jerk, but you can't ever get a battery to read zero volts. At least not without a copious amount of time or completely destroying the cells somehow. I've left battery leads twisted together for 2-3 weeks before and once you untwist them and let them sit for a day, the voltage will rebound a tad. Granted it wont rebound much but they will have a bit of voltage still in them. Just a little bit of info.

The one time I tried it I left the battery in the bucket for 2 weeks or so and most of the wires had corroded off of the cells so stripping the leads back wouldn't have helped.

You were using too much salt in your water. For a gallon of water you shouldnt use more than 1 cup of salt max (1/2 cup minimum). Too much salt in the water combined with the charge in the battery creates an effect called electrolysis, which can split the salt water in to various things like cholrine gas, hydrogen, and hydrocholric acid. The hydrocholric acid will eat up metal in no time flat.

The 2 cells I could still get a reading on were still showing over 2.0 volts.

I ran a nail through this 2S lipo that was just a bit under 2V and it did nothing. As far as I'm concerned if the pack is 1V/C or less then its safe to ditch.

At the end of the day does using salt water work, sort of but here are much faster and cheaper ways to dispose of batteries and as @olds97_lss mentioned you don't have to wonder what to do with the bucket of waste.

My own personal opinion is that salt water is fine, just test your voltages before throwing it away and make sure its at 1V or less per cell. That being siad, I do completely agree that using salt water is messy and a PITA which is why I use a fan and LED (pic below) to discharge lipos down to ~2V and then I strip the ends and twist the leads together and let it sit for a few days. Then the voltage of the pack should be less than .3V even after rebound.

However you choose to discharge your lipos just take precautions

 

[space truckin]

Just need to solder on a pair of nipple clips and I'm pretty sure you can market this on other 'hobby' websites