Battery pack of HP 25 calculator

[Graan]

I have bought a HP 25C and when looking at the battery contacts in the calculator I dont see how it will be a good connection to the batteries. It was 2 NiMH batteries (GP cells 1300 mAh) inserted when I got the calculator. The connectors from HP 25C are 2 pcb studs with traces with some slodering. What I can see there is no good contact direct to the batteries. Should it be some other arrangement?
I connected the HP 25C to a power supply and it works fine, but when inserting the batteries the calculator does not seem to work properly. The batteries are charged. Measuerd 1.3 V on battery.