Thinkpad Battery "Whitelist" ... how does it work?

[Scorpion8]

Been wondering this since I got my T430s, but how does the non-Lenovo battery whitelist work? I have always been amazed that Apple can make it so their phones will detect non-Apple "pure" charging cords and other accessories, but how? How does the machine know that a battery is NOT a Lenovo-pure battery, and why can't that be spoofed? I see many, many non-Lenovo branded after-market 81+ batteries for my T430s, at much reduced cost compared to the Lenovo-branded fodder. So why can't these be made to work without the BIOS hack?

Is it one of the connectors on the connecting pin perhaps?

[theterminator93]

I don't have much technical expertise to contribute, but I do know that this is related to the EDID chip on the battery. It's software embedded on the battery control chip - probably some kind of challenge/response from the system BIOS to authenticate the battery. Possibly similar to how OEM Windows activations work?

[dr_st]

I see many, many non-Lenovo branded after-market 81+ batteries for my T430s, at much reduced cost compared to the Lenovo-branded fodder. So why can't these be made to work without the BIOS hack?

Some of them work without the BIOS hack. I had such a battery myself (an obvious counterfeit). It worked and the laptop did not complain (I still sent it back because I don't like supporting scammers selling fake stuff as genuine; if it had been sold as "compatible", I wouldn't have a problem).