Dell inspiron 1100 turns on for a few min...

15vac is pretty normal for a laptop battery. Its likely that your laptops power inlet has malfunctioned and no longer is capable of recieving voltage. Besides, your power terminal should be getting 120vac, it's just your adaptor that reduces the voltage to 15-19 vac usuable for laptop batteries. Also your laptop computer is rather an older model, my mother has one and I've worked with it a while. Laptop batteries also don't last forever, It might be wise to move onto a better laptop.

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