LIPO getting excessively hot. Details inside

[Vivek92]

Right now I'm running a Hot Power 11.1v 1100 MAH LIPO (15c) through low resistance wiring through a MERF 3.2 (properly wired) into a tienly GT45000 motor to 16.32:1 ratio gears and MAN is this lipo getting HOT. The MOSFET stays at a nominal temperature (ever so slightly warm) but the battery gets pretty hot pretty quick when using the burst function and shooting on semi.

I'm not 100% sure what could be causing this (although I believe this battery is a POS) could it be that my motor is trying to draw too much power from the battery?

Also it is all wired to deans (and I did the wiring myself)

[Stealth]

Originally Posted by Vivek92

I believe this battery is a POS

Sounds fairly accurate. That and your secondary diagnosis is highly probable. How many amps are you drawing?

[Kos-Mos]

Your battery is way too "small" for this setup.

You need at least a 1200mAh 20C.

The battery you have, though it's "rated" at 15C is actually 10C, with 15C peaks.

Most "newer" 20C packs are actually 20/40 (20C constant and 40C peak).

Don't fuck with LiPos. If your pack seems like it's inflated (as in, you can feel that the inside is not stuck to the shell, and there is air/gaz), don't use it again. It's going to explode when you try to charge it.

[Vivek92]

Thanks for the quick response. The battery is rated 15c 20c burst (which I guess is still EXTREMELY low).

So the problem is my motor is trying to draw more power than available then?

I'm good with the mechanical side of teching still learning the electrical :P

[Vivek92]

Originally Posted by Stealth

Sounds fairly accurate. That and your secondary diagnosis is highly probable. How many amps are you drawing?

How do I go about measuring this?

and on that note would this:

http://www.hobbyking.com/hobbyking/s...arehouse_.html

suffice (1000 maH 20-40C) or would I need something a lil more powerful

[Kos-Mos]

That should work fine.

These are also very nice packs. If you get overheating with this one, you might have to recheck your shimming and swap your motor and see if it still acts up.

[Vivek92]

I shall (my shimming is good but could probably be better) I just did a little testing with a 9.6v nunchuck and a 8.4v stick both function fine with no issues (heat or otherwise) so I have a feeling these batteries are just... horrifyingly bad.

One of them started smoking a little after 150~ rounds on auto

[lurkingknight]

neo motor... drawing from a 1.1A 15C battery... you have barely enough power to power a standard ferrous motor.... leave that battery for stock guns if you haven't killed it yet.

You need a pack that can push at least 20A constant.

1.1 x 15 = 16.5A

I'm guessing even properly shiimmed that motor will draw closer to 20A if not more.

You need more mAh and/or C take your pick. Find the most you can safely stuff into where you want to put your battery. Ideally you want more of both.

[Vivek92]

Done and done. Thank god its not a wiring issue . Picked up 1200 mAh 25c-50c burst batteries should do the trick

[Knoxville450]

Im not entirely sure but I dont think its 1.1a, it is 1.1ah (1100mah) this refers to capacity like a fuel tank. It means that at one c it will discharge 1.1 amps in one hour. Do not confuse this with discharge rate or c rating, it does not mean that your battery is only capable of outputing 1.1×20c. I regularly fly my 600 size rc helicopter with a 25c battery and it performs similar to a 90c battery(both batteries produce 100amp peaks). More milliamp hours will not increase the wattage of the system. In other words voltage pushes the power down the wire and amps are determined by the power called for by the motor only. This is just my opinion and I am not as experienced with airsoft. If I could offer a guess maybe 11.1 volts is a little bit too much and the leftover voltage is being turned into heat, this is common among radio transmitter batteries. I just thought id chime in before you worry about trying to figure out exactly how many milliamp hours you need. Replace the battery if it is puffed for sure.

[K3vX]

Originally Posted by Knoxville450

Im not entirely sure but I dont think its 1.1a, it is 1.1ah (1100mah) this refers to capacity like a fuel tank.

You're right, but I'm pretty sure it's what we call a lapsus, especially when he mentions just after that the amperage is 16.5A, and provides the formula to find the real Amperage.

[Vivek92]

his formula is correct, to get discharge amperage:

1100mAh x 15C= 16 500 (divide by 1000) and you get 16.5 amps continuous discharge. So increasing the mAh or the C rating will increase amperage and therefore wattage.

[Knoxville450]

Im very sorry and I dont wanna sound like a jerk but you should know that means it is rated to have that many amps discharged from it at once. Further research will show you that c rating really is a myth and most lipo batteries can handle extremely high discharge rates like 100 plus amps. The mechanical load on the motor determines amp draw.

[ThunderCactus]

That's just a basic rough estimate formula.
The higher the C rating, the lower the internal resistance of the battery.
So where your motor draws 30A, so it stands to reason a 20C 2000mah and 100C 2000mah will both provide enough amperage to run it, so they should have the same performance since the motor won't ever draw more than 30A.
Well in practice that is not true.
A higher C rating will have SLIGHT performance advantages over a lower C rating since there is less internal resistance.
Between a 25C and 40C there is an audible difference in ROF on my guns. Not huge, wouldn't prevent me from running 25C batteries, but it does make some difference.

Also, throw that battery out. Once a lipo gets hot, it's suffered internal damage. Once it's suffered internal damage you now run the risk of it venting during the charging process.

[Knoxville450]

Thank you very much for explaining that in an airsoft kind of way I think I sound confusing when explaining