BatteryAmnesia 1.5.2

A StuffIt archive of BatteryAmnesia is available for download (152k).

BatteryAmnesia has a $10 registration fee. You can register online via Kagi.


BatteryAmnesia is a utility for any PowerBook that uses a nickel-cadmium (NiCad) battery or Nickel-Hydride (NiMH) battery. Over time, these batteries are susceptible to a "memory effect", which can reduce their battery capacity. The memory effect can be cured by fully discharging the battery before recharging it.

The Apple PowerBook manual recommends a method for discharging your battery, by running your PowerBook on battery power until it shuts down, manually dismissing the low battery warnings that periodically pop up. The big drawback with this technique is that you have to be present to dismiss the low battery warning dialogs when they come up. Also, the PowerBook software will put itself to sleep "softly" before it is completely discharged.

BatteryAmnesia provides a safe, fast and automatic way to deep discharge your PowerBook's battery. BatteryAmnesia automatically bypasses the low battery warning dialogs, and prevents the "soft" sleep brought on by those dialogs. Instead, BatteryAmnesia will run your PowerBook's battery down until the "hard" hardware shutdown occurs, which is at a lower voltage. This provides a better discharge.

Once you tell BatteryAmnesia to begin the discharge cycle, it will drain the battery as fast as possible, by using as much power as it can. The screen backlighting is automatically increased to maximum, CPU "resting" is prevented, and the hard drive is prevented from spinning down.

BatteryAmnesia will run on any PowerBook with a Nicad or NiMH battery. It will not run on a PowerBook 100 or Macintosh Portable.

BatteryAmnesia can be run on PowerBooks with Lithium-ion batteries (e.g., PowerBook 3400, iBook, PowerBook G3, PowerBook G4). However, Li+ batteries are not susceptible to the memory effect, so BatteryAmnesia doesn't provide any benefits on these models.

Version 1.5.2 (26 August 1997):

Version 1.5.1 (23 July 1997):

Version 1.5.0 (9 September 1996):

Version 1.4.0a: