You may be able to locate a new quality battery from online vendor, also from some
who are experts and very Mac-centric who are in the US & do online business...
OWC macsales.com shows a newertechnologies battery for iBook G4 models.
Note that a battery for a 12-inch model is not suited for 14-inch model, see specs
or talk/email the vendor to be sure you get what will work with your computer. Also
take note the guarantee period for some budget batteries is about half a good one.
Some may offer a clone or rebuild used battery, or just a used cell. These do not
have much if any shelf life. A new 5 year old battery may well be unusable.
•Resetting PowerBook and iBook Power Management Unit (PMU) - Apple Support
•OS X Mavericks: Reset your computer’s PRAM - same in older versions OS X
Also certain system power resets such as PMU (power management) and the other
referred reset, PRAM (parameter random access memory) may help at times.
Good luck & happy computing! 🙂