On my 1999 mercury cougar on full acceleration the battery light comes is this normal for these cars

It sounds like your serpentine belt may be slipping due to a weak tensioner.If the belt is tight then the alternator is going out.This is not normal!

I have the same trouble it is your hot wire that comes from the batery to the starter then it runs to the a.l.t it is shorting out on the exzost pipe so when it quits you have to take it to a ford dealer thanks nathan e mail peppers1 @windstream.net

I have not heard so. i would think it would have some thing to do with the belt slipping, or alternator-brushes floating,at higher RPM,s it is most likely a indecision the alternator ,maybe needing service,some time soon , unless it if a problem for you i would wait until it happens more often ,but start looking for a good deal on a new alt,or rebuilt. hope this is helpful please let us know . you can git the charging system tested for free at most Auto Zone stores. have a good day .