Extra Amps

It's not going to be that simple. The first problem is that that battery goes into an inverter before getting to the motors. The inverter is going to regulate the output to whatever it thinks it's supposed to be (if the extra input voltage doesn't kill it). You'd also need to tell the computer about the mod. That might be next to impossible for a homebrew mod.

 

Plus, the extra voltage means extra power dissipated by the inverter and that equals extra heat and that means extra shortened liftime. Not to mention how 'extra' fast you'll blow the warranty out of the water.

 

It is not that simple.
Do you know there is a step up DC/DC converter and the 201.6V becomes up to 650V?
If you have enough hacking capability, you had better to add second pack connecting in parallel.
The Toyota's gen2 plug-in prototype Prius increased the system power to 100kW by paralleling the battery.
TOYOTA: News Releases: Toyota Plug-in Hybrid

The TRC does not allow you to wheel spin.

Ken@Japan

 

Rather than try to make the Prius powerplant what it is not, here are some (silly) ideas.

Mid engine rear wheel drive V8 that spend most of it's life in Neutral.

Cast a mold of the Prius body and make a fiberglass shell, mount the shell on an Ariel Atom
Welcome to Ariel Atom

Mind you, an Australian gentleman has both supercharged and turbocharged his Gen I Prius, so it CAN be done. I keep thinking of a 201V electric supercharger project... the Road Watt-ior

Most of this guys problems would be solved if he was using a 201 volt motor. http://www.turbomagazine.com/tech/0406tur_knight_turbo_electric_supercharger/index.html

 

Can you say drivetrain? Surely the Prius' drivetrain is matched so that it is handling all the power it can. To oversize the drivetrain would be inefficient. I assume you can't tow with a Prius for this reason, the drivetrain won't handle it.
I bet the Prius has traction control that you can't turn off for this reason as well, that is the sudden "grab" of traction when a wheel stops spinning is more than the drivetrain can handle.
Most cars that have traction control have a way of disabling this feature, for snow, ice, etc. , but you can't turn the traction control off in a Prius, Why?

 

Sell the Prius and buy whatever car is being modded now, I just don't think you will be happy with it.

 

Just drop in another complete drivetrain, complete with another battery, in the back. Or just go buy a used Corvette - they are cheap enough and probably a blast to drive! and will really smoke up the tires for you.