Puffed LiPo = Dead LiPo?
 

Hello,

Last time I bashed my revo with my LiPos, I noticed that they were a tad warmer than usual after the run. Never actually hot, but slightly warmer.

Today, after the run, they were trying to bend the aluminum box I had made to hold them. Puffed and burning hot. I could barely hold them in my hands.

They're now cooling in sand and my question is: are they completely dead?

If so I'm going to safely dispose of them.

Thanks

Loa

yes.

a irreversible process has started.

You could carefully remove the heatshrink and see how many cells have puffed (those ones are dead).

If only 1 you could send to Lincpimp to see if he can remove that cell.

See lipo repair thread - else its dead...

Rgds

Some more info on your setup would be handy. Lipo brand and specs, motor, esc, gearing , vehicle weight, vehicle type, tire size, etc. Sounds like you ran the lipo too hard and at least 1 cell has puffed.

Hello,

That's what I thought, but I wanted to be sure. Thanks for the confirmation.

Since both they were severely puffed, I won't take the chance of opening them up.

I was using two 2S 8000 10C LiPos from TrueRC. I know that 10C (underrated?) was cutting it close, but it hard worked very nice so far. Since both they were severely puffed, I won't take the chance of opening them up.

Well, looks like my Revo is going to appear on the marketplace since I'm not planning on buying new LiPos... I seem to remember there being a buy/sell forum here, but it's gone. Changing rules?

Thanks

Loa

You can post a fs thread in general discussion without prices.

4s 80 amp continuous setup seems low to me. I'm suprised you didn't melt the MMM, if that's what you were using. I wouldn't go less than 100amp continuous discharge rated pack in a monter truck.

Thx, will do!

I know, that's why I said it was cutting it close. But last year when I built it, I saw many reports of ppl using the same set-up without trouble. It went perfectly fine for 25-30 bashing sessions... Was fun while it lasted!

Loa

Only 10C rating? Holy shit, you lucky you didn't fry your ESC with that low of a rating. Castle has stated they recommend 120 amps CONTINOUS or above 25c to reliabley run their brushless motors and ECS.

As I said: TureRC LiPos are supposed to be underrated, and quite a few ppl were running the same set-up last summer.

Maybe I got lucky with the MMM, but that's what happens, sometimes! :-)

Loa

That was a standard setup for a revo with a MM - The MMM lets the motors draw more amps which started to make these setups marginal.

As the batteries aged their performance couldn't keep up with the MM...

Shame you have to sell rather than get better lipos - There are quite a few reasonable options now.

Do you have a budget for replacements if you could go that route?

Bonne chance

Bah... The Revo was already for sale in a local (Quebec) forum. But sadly, most ppl here don't have a clue that brushless = nitro killing, so it's not selling. I'm betting that next year, the brushless "reality" will hit every nitro fan pretty hard.

And in any case, I have too many (expensive) hobbies! :-D I just bought a 4000$ computer+monitor, and I'm planning on spending 600$ more on it for a RAID0 and RAM. Add 400$ if you count the SSD I want to try soon. And I have a Nikon D300 + 4 lenses, and 2 more pro level lenses I'm planning on buying this fall... (At least, this second hobby is one that is starting to be lucrative! hehe)

So do I have the budget for 2 more Lipos: yes. Do I want to spend more cash on a hobby I found nobody to share/play with? Nah...

Loa

Sorry to hear your about your problems and termination of the hobby.
FYI, the 15C would have ben fine, Myself and several friends have the 15c packs for our E-Revos and have had zero issues. Luckily.
The Zippy packs are cheaper and better anyway,check them out. You may reconsider ?

Hello,

I'm having trouble finding prices for those Zippy packs... Can you give me some links? Looking for something like two 2S 8000, at least 20C.

Thanks

Loa

attend pour les prix i font des mise a jours sur le site:yes:jte le shooterai jne roule que ca des zippy:whistle:

Super, merci!

Sorry to inform you but Zippys highest capacity availible is 5000mah

Hmmm, well if the price is proportional... We'll see. :-)

hobbycity.com

they have 5000mah 20c-30c lipos for only $20 each. they are labeled as 15c-20c, but they are just mislabeled.
http://hobbycity.com/hobbycity/store..._15C_Lipo_Pack

also, for less amp draw and more power, try the 3s lipos.
http://hobbycity.com/hobbycity/store..._15C_Lipo_Pack

the 2s lipos will be ok for your setup if you gear to 40mph or less and the 3s will be even better if you stick to gearing for 50mph or less.

You don't need frickin 8000mah to get good runtimes. I bet you'll get comparible runtimes with a 5000mah 25c battery then you did with your old lazy true rc pack.

Check out the flightmaxes and turnigys on hobbycity.l

I'm not a big TrueRC fan much anymore since I've discovered Zippys but I have to give some credit to Dan at T-RC. The 15C 8Kmah Packs I bought from him have ben working great in my E-revo for a year now and they have tons of punch and balance perfectly still. I'm well aware a higher Crating will offer more power,efficientcy ETC but I've gotten my moneys worth from these packs already and there showing no signs of giving up yet. I get 45-55+ minute runs w/no problem.

Ya, that's just about what I was getting with my 2S 8000 packs as well...

But if I don't find a buyer for my Revo, I may look into those Zippys...

Loa

Well advised, even though they don't have anything bigger than 5K-mah the money you'll save will make up the difference ! You may buy (4) rather than (2) ????

You could always run batteries in a parrallel. If you had two 4s 4000mah packs and run them in a parrallel it would be equivalent to 4s 8000mah.

Excellent idea.