I just learned something. Even though my MacBook says my battery is at 84% (battery app says it's at 84% at 9% Capacity), as soon as I unplug it to run down the hall to use the printer, it shuts down. So actually next to no battery life at all. Thankfully, it still works with adapter.


Originally Posted by artie505
Originally Posted by Ira L
Originally Posted by artie505
Originally Posted by Ira L
How long is a cycle in battery life?
Each round of full discharge and then full recharge is called battery cycle life. A battery's cycle life can range from 500 to 1200. That means a life cycle of 18 months to 3 years for a typical battery.

[Note the term "full discharge". I imagine most people do not let their battery go to 0%.]
Just to clarify, "full discharge" is a cumulative computation, i.e., 20 x 5% discharges = 1 full discharge, as do 2 x 50% discharges.

Quite true. And the discharges can be over a period of days or weeks, so that the duration of a life cycle can be even harder to determine. That's why I think the maximum battery charge, rather than cycles, is a better indicator of battery life and power. And in the case of this thread, to me, 23% (or now 24%) is not a good sign.
I agree. % charge is more important than number of discharge cycles...considerably more important, in fact. And you're quite right about Rita's battery taking only a 23/4% charge being ominous (and that's to say the least).

But it seems to me that there should be some degree of correlation, and a battery that's only used up 1/4 of its life yet only takes 1/4 of a charge seems anomalous to me.

Has anybody got any insights into that?


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