Hey guys, I come here for an advice. I crashed my quad the other day and the lipo took a hit. Now I'm not sure if it's still safe to use it or if I should get rid of it. I think it's not very badly damaged, but since I have respect of these things and I like my home not burned down, I want to be on the safe side. Thanks!

Below are some pictures of what does the pack look like.

Idk...thats a tough one.  Charge it under close  supervision.  See if it heats up or puffs at all.  I have some that are in at least that bad a shape and I keep using them.  You know it's been damaged and if you elect to continue using just keep a close eye on it.

I agree with sirdude....only charge it under direct supervison, and maybe even charge and discharge on the charger a few times and see what happens.  As for me, I'm very conservative on lipos.  I would get rid of it, as the possible negatives that come out of a damaged lipo isn't worth saving the money to replace it.

That's a hard decision TBH. I don't have enough experience with LiPos to advise you but it's probably the one single thing about the hobby that worries me the most. Maybe charge it in isolation outside for the next few cycles at least and see how it fairs up. I would certainly take on board the advice offered by others who have loads of experience with handling LiPos.

This does raise the question about battery protection and something I've been thinking about recently, although I've not yet done any research. Does anyone have any kind of "protector" on their battery, and what options currently exist for that?

Like everyone said, just keep an eye on it when charging and look for heat or puffing of that cell. I have one that looks a lot like that and has been fine through many cycles since the crash.

Thank you everyone. I guess I'll try to charge it later and see if it does any funny things. Do you think that charging it with say 0.5C or even lower would be any safer if there's something wrong with it (generally if there's a suspicion, not only this particular case)? Meaning that it would perhaps give me more time to react if something goes wrong.


Maybe for the future times, I will rate the battery damage rate using the "team taco meter" I have found while googling yesterday

(03-Sep-2018, 10:38 PM)SnowLeopardFPV Wrote: This does raise the question about battery protection and something I've been thinking about recently, although I've not yet done any research. Does anyone have any kind of "protector" on their battery, and what options currently exist for that?

Some frames come with an additional CF plate that can be strapped beneath your pack to protect it from impacts. Personally I use a bit of high density foam packaging and strap that beneath my pack, its far from ideal, but offers a little protection from small sharp stones during my usually unceremonious "landings"!

(04-Sep-2018, 09:59 AM)Tom BD Bad Wrote: Some frames come with an additional CF plate that can be strapped beneath your pack to protect it from impacts. Personally I use a bit of high density foam packaging and strap that beneath my pack, its far from ideal, but offers a little protection from small sharp stones during my usually unceremonious "landings"!

Thanks for the tips. I'll try and decide if I need to do anything and if so, what to use.

My battery is on top so less susceptible to damage from a landing or failsafe, but in the event of a flip-over crash the risk does still exist so it would be good to try and mitigate that as much as possible.

So an update on that particular lipo: I charged it using while sitting right by the charger, checking the puffing, voltage and temperature like every minute (while working on my killer robot). No puffing, no increased temperature, no odd behaviour - so I figured it's okay. Yesterday I took it to fly, I took it easy, pretty much just cruising around with only few easy punches. Again, no puffing, no extra heat, so I guess it really is fine. I will however still charge it the next time while supervising it closely to be sure.

On the other hand, I had a pretty bad crash yesterday with another battery. The battery slipped on the frame during the crash (despite being attached by two straps, gotta figure out better way) and got unplugged. How fun is finding your quad in tall grass when all you have is a crappy DVR that got cut out while the quad was facing the sky? Not very fun. Not very fun for around 40 minutes... But I found it after all. The bad part is that my FPV camera mount got broken (well at least I have a reason to buy a better camera yay ) and worse - the lipo discharge leads got damaged - the negative was badly cut, the positive a little. I was lucky it didn't short. Not a good week for my lipos

(06-Sep-2018, 07:10 AM)izzy26 Wrote: On the other hand, I had a pretty bad crash yesterday with another battery. The battery slipped on the frame during the crash (despite being attached by two straps, gotta figure out better way) and got unplugged. 

That's good news for the one battery!

I know I'm the minority here on the forum, but I will recommend velcro to keep your batteries in place.  I have seen some pretty horrendous crashes in the helicopter world, where we use velcro, and never have seen a battery ejected.  I've seen batteries ruined or destroyed, but never ejected.  Not saying it can't happen with velcro, but it will be far less likely.  Given there's lots of discussions on ejected batteries in the FPV world and little use of velcro, I see a pattern.  The down side to velcro is putting it on all your batteries.  But once it's on, it will last longer than the battery.  You still use straps with velcro, but when the straps cinch down, now you have all those hooks in the velcro grabbing on.  The coefficient of friction has to be 100s of time higher than just a sticky pad.  I would suggest the industrial strength velcro as it has more aggressive adhesive to stick better to the batteries and the body of the quad.

Just a suggestion....hope you have better luck with your lipos in the future!

I agree with Krohsis here.....I use a product called Duralock.....kind of like Velcro on steroids......never had a battery eject since I started using it.

Thanks for the suggestions! I saw the use of velcro before and I think it's a very good idea. It's just that I was lazy to deal with it. Well, this experience was a very good kick in my butt to actually go buy some velcro and do that.

An alternative to velcro or duralock is a product called Ummagrip. It's pad that you stick to the quad and the battery sits on top of it. Don't confuse this as being similar to a rubber/silicone pad because it's not. It has some kind of weird sticky surface on the top that the battery sticks to really well but the sticky doesn't wear out, so you can keep removing and reattaching batteries to it. If the pad starts to get less sticky with dust/debris you just either wipe it over with a moist lint-free cloth (or a bit of spit out in the field), or you use some sticky tape to remove any crud and it becomes fully sticky again. You can turn the quad upside down without battery stuck to it and no straps on and the battery doesn't drop off. They're about $5 each so not cheap but if you only have a few quads it's a viable option.

It's extremely risky to give people advice on whether a dented battery is still okay to use.
To avoid any fire, my answer will always be no
For your existing and future batteries, here is what you can consider doing to protect them from getting dented or even punctured in crashes.

https://oscarliang.com/protect-lipo-battery/