The battery packs for the HP Deskjet 340 series printers use a Ni-Cd (nickel cadmium) battery that can be charged in about one hour using the World Wide Power Module/Rapid Recharger, or six to 10 hours internally. The Ni-Cd battery is subject to memory effect and takes longer to charge because it must be completely discharged prior to charging. Memory effect gradually reduces the amount of charge the battery can maintain. The World Wide Power Module/Rapid Recharger is designed for the HP Deskjet 340 series printer and the Ni-Cd (nickel-cadmium) battery only.
The battery packs for the HP Deskjet 350 series printers use a Ni-MH (nickel metal-hydride) battery that is charged internally in about one hour. The Ni-MH battery is not subject to memory effect and therefore can be charged before it is completely discharged.