Thinkpads Forum

I'm looking at replacemant 6 cell batteries on ebay for my T520. (Lenovo prices are just crazy)

The Lenovo oem has a voltatge of 10.8 and the aftermarket compatible ones all seem to be 11.1 volts (the mAh are the same)

Does that small difference in voltage make a difference and/or will it mess with the power manager and gauge?

The answer to your question is "No" -- the Power Manager deals with power, not voltage ... and, without getting into the electrical engineering formulas, let's just say that the power calculations will be accurate.

HOWEVER, the aftermarket batteries are not going to be the same in "performance" as the Lenovo batteries -- whatever criteria one applies: longevity, cell quality, quality assurance, fit, etc. I don't think anyone has found essentially identically performing replacement batteries for the Thinkpads. Thus -- in the larger sense -- the "savings" in buying the aftermarket batteries are largely illusory, nonexistent, even negative.

Perhaps others will offer a different perspective ...

Thanks for the response. It's a new purchase for my wife that was missing the battery.

She'll primarily be using it on ac power in the house, so I was looking for the least expensive route. If she would use it "on the road" the I'd be far more likely to go "genuine".

So, as long as the voltage is not the problem, I'll probably go with the aftermarket. (unless, of course, I can find the oem at a good price)

Edit: You were so right ! Well, lesson learned. Bought the aftermarket battery and it was a horribly tight fit. Took me 10 min to finally snap into place. Plugged in the AC adapter , green and yellw lights blinked once and that was it. The computer didn't recognize it and Power manager only reported it as an error. Fortunately, the vendor had a money back policy so I returned it and bought the OEM, which installed smoothly and charged just fine. So, all is well.