Help Getting "Not Approved Battery" warning

[Destroid]

i've had my Moment just over a year, and about 6-7 months ago i had to replace the battery. i ended up getting a new battery from a local battery shop. it's a Fujitsusakikushimoto brand. ok, not really, but it's not a factory battery, it's just some random japan battery. anyhow, for 6-7 months it's worked flawlessly, even lasts a little longer than the factory battery that crapped out on me after only about 5-6 months. well, just today i started having the warning pop up on my screen saying i wasn't using an "approved battery". it doesn't make the phone shut off or anything, i just click "ok" and it goes away for an hour or so. why is this? why would my phone just decide today that it doesn't like the battery it's used over half a year? my phone is getting really "needy" lately and if it keeps being so high maintenance it's going to be coming to a dumpster near you. i've liked the phone for the year i've had it, but in the last few months it's really became crappy...anyhow, sorry to vent...just getting a little frustrated at all the random problems it's began having after only a year of relatively light use. thanks in advance, any help would be appreciated...