Battery bloated .. KWA KR12 7.4 vs 11.1?

[Estrela]

I had this question in the noob section but it is likely better here.

I bought a used KWA KR12 off the forums here. Very happy with the purchase except for that the seller gave me an 11.1 lipo 20C.

After two games the battery got bloated and I was told I need a new battery. They tested the battery and told me it was at 58 68 68.

My gun is shooting 330FPS with .20 gram bbs.

is an 11.1 too much? should I go with a 7.4? I am a noob and although will buy a battery checker that beeps I am pretty noob with knowing when to stop firing?

What battery brand is good to get and should I go with a 7.4v or 11.1v lipo.

keep in mind it is hard to fit in the stock and the current battery is 3 seperate that I stuff into the stock.


Thanks for your help.

[lurkingknight]

what the hell is 58 68 68? what do these numbers represent? they don't represent cell voltage because max volts on a lipo cell should be 4.2v, minimum safe is like 3.2.

As to why the battery will puff up like that? You need to determine what's wrong with the gun. The output voltage has less to do with why and how it's being damaged.

There is either a short in the wiring of the gun that's leading to higher current draw than normal, either wiring, motor, or a short to the gearbox shell or all of the above.

There is higher resistance in the system than normal, were the wires getting hot? was the motor getting hot?

There is mechanical resistance so great that the motor is straining and drawing max amps from the battery.

The motor is too powerful for the battery trying to draw more amps than the battery can provide. This has nothing to do with voltage. Knowing what the mah rating for your battery is important. A rough estimate of output amps is C x amp hours, so if your battery is 1000mah it is 1 amp hour. So a battery of 20C and 1ah has an output capacity of 20 amps. Most stock guns have a constant draw from 13-18 amps. Some modified guns or motors draw over 20 amps. Startup draw when you first pull the trigger can easily triple the constant draw. Some batteries list burst ratings in the C rating which means the pack has been tested and has ability to handle amperage spikes to those levels.

If none of this makes any sense to you or you don't have proper equipment to test amp draw or voltage meters, take it to a tech that does have the knowledge and tools. If you keep shooting the gun as is will probably damage more lipo packs and potentially be a fire hazard.

[Red62]

2 games without charging? If you run the cells anywhere lower than 3V each (2.8 is extreme and probably unrecoverable), that is x2 for the 7.4 and x3 for the 11.1 (6V and 9V respectively) than you should stop running the battery.

I normally like to go, "1 BB per mAH," as just my standpoint (1100mAH I can put out like 2 high-cap mags full ish.)

Look up the Safe Discharge Levels of your battery and go from there.

[ThunderCactus]

You gun shouldn't even be able to cycle at 3.2v/cell, the dropoff on lipo's is STEEP.
It's literally 2 shots on my ptw and the battery won't cycle it anymore, and that's at 3.3v