How can you fix a psp battery

"you open the batterie slot and put the new batterie in" that's a simple answer that is very apparent to every1, I've fixed 2/3 of my batteries with my method, lol lucky i guess, but anyways i peeled case off and took a butter knife against the metal part connected to circuit board and battery, ran it across, few little sparks, little smoke blows at u = P, lol but anyways, it sumhow worked ^_^ "i dought it'll start a fire"