Aftermarket laptop batteries--any good ?

It's about time to buy a new Lithium 6 pak battery for my Dell Vostro. Naturally Dell says only use their product...$150 or more. Ebay has some aftermarket for less than $50 ! What's others experience on these non-brand batteries?

And is there an exterior back up battery pack for most laptops?

 

I just found a recent discussion on this topic ...Nov27 I think,under New Battery. It answered 1st question.

 

Batteries can be very hit and miss, even the ones that the manufacturer supplies. I have an old Inspiron 8600, probably about 5 years old. I still get at least 3/4 of its battery capacity. My daughter has an Inspiron E1505 that she has had for almost 4 years. Her battery lasted about 2.5 years. I bought her a replacement on ebay and it is still working OK. My mother has a Dell B130 or something like that, and her battery barely lasted a year.

When I was researching an aftermarket battery to buy for my daughter I looked at feedback for a lot of ebay companies that sell a lot of batteries, and all of them had mixed feedback. Lots of people got their batteries and had good luck with them, but every seller had sold batteries that didn't work out very well. Of course by then I knew that even Dell sold batteries that didn't work out very well so I thought if I was going to have to take chances, I would take chances with a battery that cost half as much.

Nobody can fault you for paying more and buying the genuine battery, OTOH you might buy an aftermarket and have good luck with it. Unfortunately you pay your money and you take your chances.