My battery for my Dell D830 Latitude laptop died very prematurely. Trying to save some money, I bought a replacement (Rayovac) at Batteries Plus. It fit fine and powered the computer, but didn't charge (charge steadily decreased). Thinking it was bad, I exchanged it. The replacement did the same. Now I assumed the motherboard was bad (three batteries not charging, what else could it be?) So I replaced the motherboard, but the Rayovac battery is still not charging. I've now been informed, "some of the replacement batteries don't work". Is this true? Can they be made to work? How can they be sold if they don't work? I'm very confused about all of this. I know the "genuine" Dell batteries are recommended, but are they also required?