The Flash is faster than the speed of light, which is much faster than a nerve impulse. That means that the Flash can bitch-slap the orphan out of Batman before an electric impulse travels from Batman's brain to his muscles.
Technically Batman could die before realising he is in pain. Thats how fast the Flash is.
You can only hit what you can find, batman is a master of stealth and would kill the flash in his sleep. Also batmans armor can make him a human tazer that would stun the flash long enough for batman to get a hold of him and deliver a killing blow.
Batman is a super rich martial artist who fights crime by his own hands, he has the tech and the money, so how can he win against a guy who can move so fast you dont even see him? tricky huh? here's how...
It can happen if he creates somekind of a pulse device and makes say... 4 devices like that and places them in a big area creating somekind of a square , theyre not connected by anything but when activated the waves they send create somekind of a force field that shocks anything inside of that square and slows the objects atoms or something so he makes the flash... a normal dude for a few mintutes.
Given enough prep time and resources, Batman ALWAYS wins. Always. Check out the animated movie "Justice League: Doom." It's all about how Batman is capable of single-handedly defeating the entire rest of the team, despite being the only mere mortal on it.
"im flash and im the faster man alive" everyone is faster than him xD please... i like the serie The Flash but makes no sense he saying that over and over when he isn't... for not talking about some wrong stuff that goes on