The cells are junk. They have been sitting too long. Batteries have a capacity loss of so much per year, per temperature scale, and is also dependent on level of cell charge. Knock on wood, the 3400 battery I have still holds a decent charge, and is original to the machine. not NOS.

Would have been more productive to get a NOS battery, and swap the cells while the controller was still fresh and had a virgin EEPROM. But, Eh...