My ThinkPad T43 After almost 15 year of Ownership still in Mint Condition like brand new with good factory battery. I just repasted and reinstalled it, Optimized as well. : r/thinkpad
IBM Thinkpad T43 Battery
Battery for IBM ThinkPad T40P T41 T42 T43 R50e R51e R52p 92P1062 92P1064 08K8192 | eBay
Changing the cmos battery on my old Thinkpad T43 - YouTube
IBM Thinkpad Battery Re-Celling Battery Rebuild Tutorial - Thinkpads Forum