Alternator/generator/regulator problems of the 2002 Mazda MAZDA6

I have a 2002 Mazda tribute ES v-6, I purchased in February, 2002. I began complaining of electrical issues (. . . Specifically battery charging/maintaining charge), at 15000 miles. Initially, the car would lose battery charge; but in January, 2005, the fuel injection system would not operate properly. The battery was determined to be faulty; and was replaced at no charge. The mileage was 29,527. April 22, 2005. . . I was in the west-bound lanes of interstate 90, in spokane, wa. The freeway is under construction, with 3' shoulders; then concrete barriers. It was 5:30 pm, rush hour. The car died completely; not even enough electrical power to activate the emergency flashing lights. I immediately dialed 911 and the state patrol; as I could see the potential, for a major, multiple car crash! I exited the car and got outside the concrete barrier, running back about 100 yards; waving to the oncoming traffic to slow down, and "merge. " I then ran back to the car; and got out my emergency battery booster, attaching it directly to the battery. I was frightened of being rammed; but felt it important to warn oncoming traffic. The booster had enough reserve power, to start the engine!! I drove down the shoulder, with the hood up; until I reached the next exit. I pulled off on the shoulder, clear of traffic. . . Fearful the booster would not keep the car running much longer. The state trooper pulled-up, and congratulated me for "being very courageous; but perhaps foolish. "she could see the west-bound lanes, from pines road, where she crossed the freeway, to get to me. Traffic was "backing-up" very quickly. . . And far to the east! she was very surprised there had been no major accident. The dealer informed me, the battery was defective. The battery is only 3000 miles "old. " is there an ongoing electrical problem, that will leave me stalled again; or cause a fire?! there are ongoing problems with the suspension, transmission, and valve train.