Batteries are getting hot and puffing

[ethomp]

Just got an Aqua Craft UL-1, using all stock components [60 amp esc and 36-56 2030kv motor] Run times are only 5 to 6 mins. with gens ace 5000mah
40c 2s. Motor and esc are comming off pretty cool but batteries feel to warm to me and now after a few runs their puffing. Never had this problem with my rc cars and trucks. This battery in the pics just puffed at the very end. Not sure what to change to stop this. Thanks
Eric

[photohoward1]

OK what Prop? Your RC cars never Drew 60 amps. When you recharge the Batts how much are you putting back into them? 6 minutes of run time is way to long.
The rule of thumb is 80%. never go below 20% left in the tank. 5000mah cells that means 4000mah used or 1000mah left in the cells. If you are taking them to zero then they are already ruined..

[Make-a-Wake]

Yeah............"only" 5-6 minutes of runtime is very long for 5000 mah...................do you have an LVC on the ESC? What voltage are the cells after a run? 3.7v per cell is depleted in my book.

[ethomp]

The prop is stock L40x57 and the batteries come off at 3.5 to 3.6v the esc is supposed to have a built in lipo cut off. so how long should a 5000mah battery run for on this type of boat?

[Make-a-Wake]

Coming in at 3.5-3.6v is every bit of 100% depletion to me........................there is no standard for runtime, its all based on the entire setup, but I think it should go 4 to 4 and a half minutes myself.

[ethomp]

Thanks for the info, I had no idea how long to run this, just ran it untill it started to slow down or untill it stopped.

[Make-a-Wake]

Thanks for the info, I had no idea how long to run this, just ran it untill it started to slow down or untill it stopped.

Thats not good news..................let 'em sit overnight and recharge them under supervision. I bet they take more than 5000mah. I have had a couple lipos swell just a bit and continued using them conservatively and they have worked well.

[785boats]

The ESC does have a cut off but it is set at 12V or 3.0V/cell. With the higher 40C rating packs the voltage curve stays up above the cutout setting longer under load & the battery fully discharges its capacity before the cutouts are actuated. By the time you get the boat untaped & measure the voltage it has recovered to 3.6V. The old 20C & 25C packs would drop down in voltage while there was still some capacity left in the tank.
You are going to have to cut your run time as Make-a Wake suggests.

[Brushless55]

Yeah............"only" 5-6 minutes of runtime is very long for 5000 mah...................do you have an LVC on the ESC? What voltage are the cells after a run? 3.7v per cell is depleted in my book.

The prop is stock L40x57 and the batteries come off at 3.5 to 3.6v the esc is supposed to have a built in lipo cut off. so how long should a 5000mah battery run for on this type of boat?

the fault of the stock esc is the lipo cut off
it has a stutter bump at 12v and cut off at 11.6v, that's 2.9v per cell!
and having better packs like these lets the cell go lower than other packs would

[Make-a-Wake]

having better packs like these lets the cell go lower than other packs would

You're exactly right.........................if he had cheapy 20c's they would have cutoff much sooner.

[Brushless55]

You're exactly right.........................if he had cheapy 20c's they would have cutoff much sooner.

I had some 20c in my UL-1 on it's first few runs, and it would cut out and still leave my cells at 3.75+ per cell..
but after learning from OSE and other forums about the 20% rule.. I time all my runs, Lipo cut off or not..

this is the very reason I tell others not to run their rc down to LVC, land, air, or sea..

[siberianhusky]

I run the same combo with a number of different brands of battery in a few different boats, set my timer for 3.5 minutes then finish the lap and bring the boat in, about 4 minutes runtime. High 60 to low 70 amp draws, last week I saw spikes of 109 amps on take off in my SAW cat! Didn't think the esc would take that!

[Brushless55]

I run the same combo with a number of different brands of battery in a few different boats, set my timer for 3.5 minutes then finish the lap and bring the boat in, about 4 minutes runtime. High 60 to low 70 amp draws, last week I saw spikes of 109 amps on take off in my SAW cat! Didn't think the esc would take that!

I'm running a constant 80a through my P-Spec DF33 UL-1 powered machine..
that motor is a monster!

[ethomp]

Well guy's, I've learned alot in the last 24 hrs. thanks to all your responses. I also found the Aqua Craft UL-1 section right here on OSE and I found several threads that talked about this very subject. Comming from 1/0 touring car and some 1/8 off road, the batteries last much much much longer and there is nothing in the owners manual that covers the use of these newer high power batteries. I have one battery I use for race only, Revtech 6000mah 60c. I'm sure if I had 2 of these I would have used them and would have destroyed them and at well over $100 apiece NOT GOOD!!! So I'll be looking for some low cost soft packs. Thanks again,
Eric

[mtbenjamin77]

Well guy's, I've learned alot in the last 24 hrs. thanks to all your responses. I also found the Aqua Craft UL-1 section right here on OSE and I found several threads that talked about this very subject. Comming from 1/0 touring car and some 1/8 off road, the batteries last much much much longer and there is nothing in the owners manual that covers the use of these newer high power batteries. I have one battery I use for race only, Revtech 6000mah 60c. I'm sure if I had 2 of these I would have used them and would have destroyed them and at well over $100 apiece NOT GOOD!!! So I'll be looking for some low cost soft packs. Thanks again,
Eric

get some sky lipo 30c from hobbypartz about $40.00. I've been running my SV27 on 5s2p with the aqua 60amp esc. I run it down till it cuts off almost everytime. I'm putting 2800mah back in a 2650 mah pack. And still no puffing and they balance just fine. the best part of it is if i do ruin them they're only $40 not $100+.