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fessen

macrumors regular
Original poster
I am looking for a backup battery (or batteries) to keep a MBP running when utility line power is unavailable.

Anyone know of good posts/threads here or elsewhere covering the major considerations for making a purchase? For example, how to estimate how long a given battery, based on its advertised specs, should be able to keep a laptop powered, or how many times it should be able to recharge a laptop's internal battery (if that's even possible) on a single charge of the external battery.

(Yes, I know how to use search engines. Hoping for some suggestions from people who have already weeded through the useless stuff and have found worthwhile sources.)
 
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