wireing battery"s in parallel

Hey guys have a question for you.I tryed to wire 2 14 volt 4000 mah batterys
in parallel to give me 8000 mah for more run time,is this correct? But when
i pluged the batterys i got a huge spark and a good size fire ball! Melted
the deans plug to nothing.Everything still works thought,what did i do wrong?
Need help from the experts!

[magman]

Check this page and click on the parallel icon and a picture will pop up to show picture


http://www.scriptasylum.com/rc_speed/_lipo.html

[BrianG]

This is why I personally do not suggest parallel connections. In order to safely hook batteries in parallel, they must be very close in voltage, preferably exact. I would charge them both up to get a fresh peak and then hook them together.

But, judging by your description, you probably shorted both batteries. Parallel connection is done by hooking the + wires together and the - wires together. Sounds like you hooked the + and - together, which shorted the batteries. This generated a HUGE amount of current; enough to melt the plugs.