I have 2 friends in the Model R/C business.

The LiPoly batteries are great on a small scale, and light enough for model airplanes and helicopters to fly via battery instead of gas.

I asked about chaining 30 ( or 90 ) of them in series for FULL SCALE car use, ie. FEH.

He said they would explode or catch on fire the first time I used them.

Also... a big downer is... you have to charge each cell one at a time.
You cannot charge in series... only parallel...

I guess, if one or more cells in a series is a 'slightly' different voltage, it really screws things up... like the lowest cell sucks all the juice, doesn't pass any on to the other cells, and in the process, probably overheats and explodes.

The R/C cars that take 3 cells actually have separate wires for each cell.