Off-brand laptop batteries?
I tend to err on the side of paying too much for quality stuff, but $180 for a standard replacement battery for a Dell laptop makes the $80 knockoffs look pretty tempting. I wouldn't consider it (batteries really aren't something I want to take a chance on getting a refurb with) - but I was so surprised to learn how popular off-brand server rails are, that I thought I'd fling the question out there and see what stuck.
I got my replacement battery from batteries plus for my laptop. It's worked as good as the original HP battery when it was new. In fact according to Linux it's still at 100% the batteries rated capacity and it's about 6 months old now.
It wasn't as cheap as the batteries on ebay but it all came down to if I wasn't happy with it I wanted the option to take it back and deal with a real person. I also didn't want to wait the couple of weeks it takes an ebay transaction to go through and get the shipment.
I bought a off-brand replacement battery for my old/spare Fujitsu laptop in Thailand. I happened to be over there so I stopped by their "IT Mall" in Bangkok.
I paid something like $50-$80 for it and its been working great for over a year now.
Basically your laptop battery is nothing but a certain number and type of cells put into a plastic case. There's really not a whole lot of difference between "Dell" and generic provided that the generic cells are reasonable quality. You're paying for a brand name.
If you're feeling really adventurous you can CAREFULLY take the plastic battery case apart and figure out which cell(s) are bad then simply order replacements (or all brand new ones) and solder them all back up.
I HIGHLY recommend buying the types of cells that already have the soldering tab attached to them as soldering directly onto the end of a battery can be a bit dangerous (ie. heat) if you don't know what you're doing.
But the short answer is... go for it... buy the generic battery. Most of the time they work just fine. Avoid the total "bargain basement/too good to be true" deals though.
Hope this helps.
When making your decision just remember that Dell don't make those batteries, they buy them in, so in some respects there is no such thing as a genuine Dell battery. $100 is quite a lot of money for a label.
I haven't tried non-"genuine" batteries in Dell laptops but I have tried tried them in several other brands. If it wasn't for the label I would never have been able to tell the difference.