Yep, that's the culprit.. When an alternator goes out it's no longer furnishing free power and since the entire system depends on this power, it must draw it out of the only source available.. You guessed it, the battery.. Essentially, the only role a battery plays is to start the car and maintain the accessories, without the generating power of the alternator to supply a constant charge to the battery, the battery would quickly fail (especially at night) and, depending on the drain can suck a battery dry resulting in damage to the cells So, it's a continual circle that must maintain it's link.
especially if it is not compatible
Other people asked questions on various topics, and are still waiting for answer. Would be great if you can take a sec and answer them