Inspiron 1520 won't charge

I've had this laptop (dell Inspiron 1520 service tag: 1552QD1) for about 16 months now, and for the most part it's been great. Up until recently, and I've googled everywhere and it seems that this is a probem experienced by almost all Dell laptop owners, my computer won't charge at all. It recognizes that it is plugged in, as that is the only way I am able to use my computer now, but it stays around 25% power level. Because of this, my computer runs exceptionally slower, freezes on a regular basis, and will turn off if my computer comes unplugged even for only a minute. I am very pissed as this has just happened recently and I am now no longer under warranty to be helped by Dell. I don't have the money to start pumping out the dollars to even attempt to resolve the problem as I am a college student. The prices of the parts that could resolve the problem (battery, adapter) are very costly, and who's to say that those are even my problems. Then beyond that, trying to pay for a tech to fix it, is ridiculous. But I really need this problem fixed and soon, because my computer is my life (I'm an engineering major) I need this for everything. I pray that there is someway that you could help me, but at the moment, all hope seems lost.