Question: What to do? Why no charge? Should I just buy another battery?

G4 Powerbook 867MHz

The current battery is the second battery, (it was replaced by CompUSSR under warranty).

Coconut says the battery is at 78% capacity (3389 mAh)

The charge however remains at 0%

Additional information:
Battery-Loadcycles: 20
Charge Connected: Yes
Battery is charging: No

Battery Info:

Power Products

14.8 Volt 4400mAh Li-Ion Battery Pack
Re-order Part Number : B-5902

Barcode Serial Number: BA0205419SIC

Other sticker: IM008772