I am not a expert on electric so this is a better safe then sorry maybe stupid question. I have a FLIER 250 amp boat speed controller.I received it from chris fine at fine design with connectors already in place. I wanted to test my system before putting it in the boat. I also have a 6s.22.2 volt 65c 5000mah battery also from fine design with connectors in place.I went to connect my battery to the speed control and when i go to connect the second lead no matter witch one i try first I am getting spark and a good crack noise. Is this normal? It is like touching the bare leads of a battery together. Is there something in the esc that would allow this connection to be complete? one lead is red and the other is black, one with male and the other with female connectors so it can not be backwards unless unless its conected to the esc wrong under the manufactures shrink wrap.

It is possible to get a spark when connecting the battery, it has happen with me more than once and it was not a problem, only make sure that you are not connecting the cells backward. But order wise, I don't think that is something to be worried about.

Completely normal with high voltage set ups. It will damage your connectors though. to alleviate this problem, install an antispark system.

Thanks guys great information.

There is probably a LARGE capacitor at the power input end of the ESC, which sits there uncharged until you apply power by connecting the battery. It then charges as fast as possible, giving the spark. for a few brief milliseconds, it is effectively a short circuit until it charges. An anti-spark connector does the connecting in two stages, the first through a resistor that limits the initial current below the spark forming level, the second is the real power connection but this happens to a fairly fully charged capacitor, so no huge current.
The sparks happen because as the connector points connect, they start with a very small surface area which is nothing like big enough to carry the inrush current and the contact points get very hot very suddenly. They are bits of the metal burning away. When the contacts are fully made, no problem until the day comes when the burnt bits get too big.

I understand, was hoping it was right but A question cost nothing so I am glad I asked and now i know more then i did before, thanks again.