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Threads: 26
Joined: Aug 2005
I have the service manual and technical manual for the Portable Plus (along with 2 of the machines, video interface, and so on...)
Anyway, the battery is a lead-acid unit. Most machines came with a Panasonic 'block' battery, which may be hard to obtain. The service manual photos show a pack made up of 3 Cyclon cells (2.5Ah ones), which are available AFAIK. You need to connect them in series and connect them to the terminal board from the old battery.
One problem is getting the battery in/out. The manual tells you to bend the connecting strips out of the way, but to fit new ones every time. Experience of others suggests that they do break off very easily. I find it best to slacken the nuts holding them to the PCB so they can be moved off the battery terminals without bending, then to take the case apart, and then to remove/refit the battery.