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-   -   What i did wrong ? (3 batteries to trash can) (https://www.rctech.net/forum/electric-road/470883-what-i-did-wrong-3-batteries-trash-can.html)

Tabushi 01-13-2011 03:13 PM

What i did wrong ? (3 batteries to trash can)
 
Hi guys,

Didnt raced for the last 4 months, now im preparing my cars for the season and took my 3 racing lipo packs (7.4v hardcase roar approved) wich were without usage during 4 months, 2 of them stored on STORAGE mode of charge and the other one 3/4 charged.

The thing is that i put the 3 batts on 3 different chargers at the same time (each one 5.200mah pack, 40c) on balance-charge mode at 2.5amp.

The 3 batts finished the charge no problem,i disconnected them and thats it. Next day morning 3 of them were inflated like triple hamburguers !!! ... they even broke the hardcase off !! ...

So, WHY IN THE HELL this happened ?, im mainly a nitro racer so i can accept that i did something wrong, but i still dont see that really,

Now i have to buy new batts.

I use 11.1v lipo pack on my radio and 14.v pack on my starter box for nitro cars now im afraid to try to charge them too !!

thanks for your time guys,

tunerjetta29 01-13-2011 04:35 PM

Left them over night? Your chargers have an automatic cut off and designed for lipos? Sounds like they overcharged severely and your lucky you still have a house.

skypilot 01-13-2011 04:41 PM

Quote:

Originally Posted by tunerjetta29 (Post 8483383)
Left them over night? Your chargers have an automatic cut off and designed for lipos? Sounds like they overcharged severely and your lucky you still have a house.

thats not what he said..

BCbud 01-13-2011 04:49 PM

Good day!

What make of batteries? What make of chargers and are they all the same? Where the ballance cables conected all the way? Did both cells puff or just one?

I may not be able to answer your question but this info will help others help you.

scottmen 01-13-2011 04:49 PM

I read that you are supposed to pull them out once a month to make sure they are still at the storage voltage. They discharge even when not connected.

This was one of the most informative sites I read about LiPos

rchelicopterfun.com/rc-lipo-batteries.html

tunerjetta29 01-13-2011 05:29 PM

Quote:

Originally Posted by skypilot (Post 8483412)
thats not what he said..

Yep, must have skimmed the disconnected part.

Tabushi 01-13-2011 05:31 PM

Yes, they were charged, and unplugged from chargers and they were puffed next morning.

3 charges, 2 of same brand one different, respectable brands (dont want to go into that hehehe) ... i charged couple of batts from a friend last week no problems at all (all were in-use batteries) ...

Batts were IP 5200's ...

clittle 01-13-2011 06:03 PM

Were they subject to a fairly significant temperature change during the evening?

ballsagna 01-13-2011 07:55 PM

hamburger'd

pics?

Dragonfire 01-14-2011 06:22 AM

You shouldn't leave lipos fully.charged. Everyone who comes from the.old.nimh days remebers.how.nimh batts where.pushed to the point where packs were only.good.for.a.single.meet. Lipo is going the same way with racers asking for higher and.higher c ratings (like it makes any difference) and packs are once again heading towards being more and.more volatile. If you want to prep a pack for racing try around 80-90% charge and quickly top it up at the track. Keep it at this.level.for the minimum time.possible.

At the end of the day it is safer to turn up to the track and charge at 2C than bring you packs precharged from the.day/night before.

nexxus 01-14-2011 06:27 AM

I don't necessarily agree with that, part of the initial sales pitch of Lipo was that we can charge them and not have to run them for up to a week, any storage beyond a week was when you put them into storage mode.

My understanding was that the higher C rated Intellect packs did tend to puff a bit.

Dragonfire 01-14-2011 08:13 AM

Quote:

Originally Posted by nexxus (Post 8486113)
I don't necessarily agree with that, part of the initial sales pitch of Lipo was that we can charge them and not have to run them for up to a week, any storage beyond a week was when you put them into storage mode.

My understanding was that the higher C rated Intellect packs did tend to puff a bit.

Intellect packs always have some.problem... It seems to be their moto. The.chemistry of.lipo's is changing to give more and more.power, but like nimh's there has to be a downside. Lipos are already like nimh's in the way that you need to treat them properly or you will kill your packs. 6 Months from now we will probably be buying a "lipo nurse" for storage between meets....

rccartips 01-14-2011 05:51 PM

I have cheap 5200/50c lipos that I sometimes leave fully charged for over a week. Abused weekly and never balanced. None of them have bloated.

Probably a product defect if a lipo bloats by simply being fully charged for 24 hours?

RedBullFiXX 01-14-2011 07:12 PM

Some Model Car battries puff more than others ;)

SpraydbySprague 01-14-2011 07:22 PM

Quote:

Originally Posted by RedBullFiXX (Post 8489283)
Some Model Car battries puff more than others ;)

:lol::lol::lol::lol::lol:


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