I have a mid-2010 MBP 13". With the old battery, my macbook wouldn't turn on unless the charger was plugged in. So I bought a new battery that I just installed (along with 16 gb ram ). The macbook was able to turn on right away without the charger and everything seemed to work great. After 30 minutes or so, my macbook shut off by itself. I don't know if it went to standby due to idling, or if it just shut off due to the battery. But it's back to square one and I need to keep the charger plugged in for it to turn on. The battery indicator said that it needs to be replaced (even though it's brand new). The battery is also not charging and stays at 53% with the charger plugged in (it came with 75% charge when I installed it and turned it on right away). I tried unplugging and replugging the new battery, but it still won't turn on without the charger. I tried resetting the SMC but it didn't do anything. I don't even know if it was actually reset because nothing really changed. My question is, could there be some other problem that doesn't have to do with the battery that is preventing the macbook from turning on without the charger? Or maybe the new battery I just bought is faulty? What do you guys think? Any help is appreciated!