Some comments about generic laptop batteries – I am happy to report that the generic battery I got for my Lenovo X61 tablet for $28 has been working well. As of now, after having it for a few months, it still gives me about 3 hours of “normal use” per charge.
My advice is to get the higher n-cell with the highest wh you can. However, batteries with more cells tend to be bigger. For the Lenovo X61 tablet battery, the 8-cell battery “sticks out” even more than the 4-cell. (You will know what I mean if you have one of these tablets.) The specification for my original 4-cell battery is:
14.4v, 4.55ah, 66wh || Fru: 42t4661 || Asm: 42t5209
The v, ah, and wh numbers are slightly different sometimes when you look at the various generic batteries on eBay or Amazon. Only after some googling, did I realize that 14.4v * 4.55ah = 65.52wh (i.e., 66wh).
The battery I got from eBay is from a seller named “buyingsnow.” (Example here.) I think the listing title he uses for the x61 tablet battery is “40Y8314 40Y8318 Battery For Lenovo X60 X61 Tablet PC.” Note that x61/x60 batteries and x61/x60 **tablet** batteries are different.
I don’t have the original eBay posting saved – so I do not remember what the exact specification were for the battery I bought. Based on what Lenovo’s power manager is telling me, it is a little different from the example of the eBay auction I linked:
If I set the brightness to 8, turn wi-fi on, and do just mostly word processing and web browsing, the battery lasts me 2 hours and 45 minutes at the max performance setting. It will probably last longer if I use a more efficient power profile.
At the end of the day, the decision is whether to take a risk on a generic battery, and get something like this:
or this:
.
The alternative is to get it on Amazon. The batteries there seem a little more expansive than eBay, but if the return policy is friendlier, then perhaps the markup is worth it. I don’t know how friendly the return policy is though when you buy things from a third party on Amazon.
In an ideal world, I would see many reviews on the particular battery I want on Amazon. The reality (here) is that some of the battery have good reviews (here), some have good reviews but are pricy (here), and some have no reviews at all.
To sum it up, buying a generic battery still seems like a crapshoot. Here I offer you one observation that ends in a good outcome. Good luck finding your replacement.