last week sometime my battery was dying so i pulled it out and replaced it with one from a different car, now the new battery is doing the same problem, basically its only happened at night so far but that could be just a coincidence, but i'll be driving then my rpms just drop and i can barely keep the car running and eventually it'll die. my lights start to dim and eventually go out as well and the car doesn't even have the power to lower the headlights.

so i get a jump start and try from there starting with 12 volts i can make it maybe half a mile down the road and then it'll do the same thing until i have to stop completly again. at which point its reading no power on the gauge and i have to get the car jump started again. i think i might need a new alternator but even after a jumpstart would the battery drain this fast? or is there something im missing.

 

You need to have your charging system tested. Your gauge probably shows that it is not charging. Most likely the alternator. Once you start the car the battery has little to do with powering the accesories or lights.