Lipo Batteries Dead after two runs

[benjijames]

Hi everyone. I have a stock miss geico. The only modification I did are octura x642 prop and dean / bullet 5.5mm adapter for the batteries. My problem is that after only two runs on 2 x 2S lipo batt, the batteries went hot, swelled and don't work anymore. The boat and its components were completely cold when I put the batteries. The batteries are zippy flightmax 5000 mah 40C. I have ride the boat 8 minutes continuously on a lake.
The set up on the programming card was low cut off voltage, the cut off type was slow down and the timing was on high.
I am really disappointed. Does anyone has a solution so that I don't encounter anymore this problem ?

[maxmekker]

I have 2x 2s 4000mah packs and I can run for about 4 minuts with lvc at 3,0v on my T180 esc/stock motor with a prather 215 prop.
they then come in at about 3,4v

When I got the MG I did not have the P card , so I timed my runs with 2x 2s 5000mah packs that I borrowed to about 4 to 5 minuts and that was stock boat all the way. If I remember right the pack's were about 3,8v whith a 4 to 5 min run stock.

I would say 8 minuts is a bit on the long side, did the lvc not cut in before ?. Have you hooked up the packs to the charger to se what the voltage was after 8 minuts. How do you charge them ?(balance ore not) what type of charger ? New ore old packs ?

[benjijames]

Thanks for your answer. My batteries were brand new. They are balanced on a turnigy accucell 6. When I say 8 minutes, it's an assesment, I didn't time my run. I just stopped the boat when it started to slow down. The batteries are completely dead, they have swelled, when I connect them to the charger, the voltage is betwenn 1 and 2 volts.

[maxmekker]

wow, now that's low.
Head over to :

http://www.rcgroups.com/batteries-and-chargers-129/

and try to get some answers from either tjinguy ore Julez , they have helped me out before.
but if you're charger has some menu settings like the icharger 3010 i have try this:

Set balance speed to slow, balance trickle on.
Disable both capacity and time limit.
Balance charge with 200mA for a long time.

That got some packs in the 2,5 v range up and running for me, but they were not swollen. Not sure about that though, I would probably get some new ones eveen though thats not fun.

[Doby]

You killed your batteries by running to long...with LiPos, when the boat slows down, its to late.

[kookie_guy]

plus your cutoff should be set to high if you are actually planning to run til it hits cutoff

[LiPo Power]

How is that some people are running their bats for up to 15 Minutes!!! ( well lets pretend I do not know )

http://forums.offshoreelectrics.com/...ad.php?t=25874

Post#1

You killed your batteries by running to long...with LiPos, when the boat slows down, its to late.

[GP73]

Did you select Lipo batteries in the programmer?

According to the [programmer manual the Lipo low voltage cutoff is 2.7v, the NiMh low cut-off voltage is 0.7v.

1) Re-program the ESC for Lipo batteries, high LVC, hard cut-off and low timing.

2) Dispose of those batteries before they explode, saving $50 is not worth the risk

3) Buy new batteries.

Hi everyone. I have a stock miss geico. The only modification I did are octura x642 prop and dean / bullet 5.5mm adapter for the batteries. My problem is that after only two runs on 2 x 2S lipo batt, the batteries went hot, swelled and don't work anymore. The boat and its components were completely cold when I put the batteries. The batteries are zippy flightmax 5000 mah 40C. I have ride the boat 8 minutes continuously on a lake.
The set up on the programming card was low cut off voltage, the cut off type was slow down and the timing was on high.
I am really disappointed. Does anyone has a solution so that I don't encounter anymore this problem ?

[d.a.v.e]

I did the same thing with my first lipo pack.. Made for an expensive $130 one time run

You should expect about a 5min run and your batts will be just about dead, bring it in.

I wanted more run time so I bought 2 4c packs I run in parrell. So far it works pretty good and nothing is getting too hot but I replaced all my connectors to EC5 prior things were all a bit warmer.

[NativePaul]

Wow 2.7v is way to low for modern LiPos thats only suitable for old gen1 6c packs a modern pack should have a cut off of at least 3.2v, or 3.4v for preference.

[GP73]

That's why he should choose high LVC instead of the low one.

Besides, I'm assuming 2.7v in under load, which is probably well above 3v per cell at rest. I run my LVC at 3v and the lowest cell is usually around 3.5v.

I am NOT endorsing this, I'm just reporting it. Keep your cells above 3.4v and you'll be happy.

Wow 2.7v is way to low for modern LiPos thats only suitable for old gen1 6c packs a modern pack should have a cut off of at least 3.2v, or 3.4v for preference.

[Blockhart]

I run mine programed at high cut off, slow down, high timing and have had no problems.

[Insaniac]

Use a programmable ESC with a soft LVC so you can bring the boat in when you get to the cutoff point. You can set the individual cell cutoff voltage to whatever you want...