The 500 series PowerBooks do not automatically perform a deep discharge of the batteries before recharging them, nor is a deep discharge recommended. To do a deep discharge, you would need to use an external device to drain the battery below recommended voltage levels.
The recommended procedure is to use the PowerBook on battery power until you see the battery level warning dialog box displayed, be sure to save any files that you are working on. Continue to use the PowerBook until the unit goes to sleep automatically, then connect the AC adapter and fully charge the batteries. It is recommended that this procedure be performed every 90 days.
The nickel-metal-hydride batteries (NiHy) can develop a "memory effect" but they are much less susceptible to it then other battery technologies are. Following the procedure above as well as the other battery care tips listed in your PowerBook users manual will prevent the batteries from developing any "memory effect".
You may also want to read the Tech Info Library article, "PowerBook
Ni-Cad Batteries: Memory Effect".
Article Change History:
06 Jun 1995 - Reviewed for technical accuracy.
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