Edit: I also realize now that you said it went in the floppy drive area so it probably is a much less powerful battery.. I almost want to say something that size wouldn't last too long if at all. But for $20 its a good price to at least test, and if you have to get the other battery, you'll have both for even better life.
Another thought though is that older Dell Inspirons used floppy slot batteries and those ran fine, so you might be able to pull it off
(for some reason the quick reply and editing isn't working right now
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