I had the same thing happen to me.
Was driving and the vehicle died for nothing.
All the electronics worked inside and out.
Turn over the ignition and nothing. Not Even a Click!!!
Paid for a tow from side of the road to the mechanics shop.
Guy laughs for a minute and comes back with a screw driver.
Screws the negative terminal clamp on tighter than hell, no problem since.
I felt like an idiot. But how the hell was I supposed to know.
The batterie was new and I torqued everything down myself???
Needless to say; try replacing the cables before you scrap the project.

2002 4dr Kia Sportage 4X4
Tires:235/75/15, Wheels: Black 15x8 Steel ProComp 2.5" B.S., Hubs:Warn Manual, Lift:3" UPYOURKIA, Trailer Hitch, Cargo Rack, Clinometer.