The car is a 98 Honda Civic. I've replaced the battery twice in the past year and a half for the same reason. The car is cranking but won't turn over. I can jump it and unplug the battery so it's not the alternator. After I jump it it'll start back up for about 2 hours then it requires another jump. I suspect that I might need a new battery now but what might be the underlying problem? Let me know if you need more info. Thank you for your time.