I've had more than a few old Toughbooks in my hands and I'm often amazed at the quality Panasonic built into their batteries. Today I got ahold of a CF-M33, the first tiny Toughbook. It was born on Nov 1998, more than 15 years ago, and probably has the original battery. I charged the battery several hours till the light turned green. This came from an estate sale so likely this is the first time in years the battery has seen a charge. Booted it up and got the message about bad date & time, so the CMOS battery went dead. Check BIOS then booted to Windows 95 :nostalgia: Set brightness to max and watched the power meter. Over the last *2 hours* it has slowly and evenly run down to 10%, just got the low battery warning at 1:53 hours run time. I know Panasonic makes their own cells and often pleasantly surprised to get a well used battery that still hold a good charge, but .... 2 hours on a tiny battery made 15 years ago that probably has not been charged in many years .... simply amazing.
Got a few CF-M34 and CF-28 batteries that still perform well too. Gotta hand it to Panasonic, they sure know how to make a great performing battery (and a few other things too).
ToughBooks: CF-74 73 53 52 51 31 30 29 28 27 25 19 18 08 07 C1 C2 F9 H1 M32 M33 M34 R2 S10 T8 T5 T4 T2 U1 W2 Y2 VDW07 PDRC ...
GoBooks: VR-2, XR-1, IX-260+, IX-350