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<QUOTE> 2. hhmm depends what your gonna be doing/if you have access to powerpoints if you need it. i would be inclined to say yes, because i am a "just incase" type of guy. but then you have to make sure its charged (its very hard to charge 2 batteries when u get home at 10 at night and have to get back up at 5), have it actually with you (im a forgetful person).
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Yes that's exactly the point. On my current (dying) pc laptop I alternate the batteries every few days. Sometimes before a trip I will make a point to ensure one battery is charged then swap batteries to make sure the other is also then I know I have plenty of charge. But it isn't often that one needs to work for more than a couple of hours away from a power supply - so the main advantage would be in making the batteries last longer and being sure that one has another battery (by the time I needed a new battery for my previous laptop the batteries were obsolete and I couldn't get one). So really this question is whether that kind of life - a few days in use then a few days off possibly in a partly-charged state is good for a battery and whether one would get more total life from two batteries used that way than one. I am also unfamiliar with the mac software/hardware relating to charge-level, calibration etc. but I read things on the forums about battery life indicators and so on and wonder how these will relate. With my current non-mac set up I just use the batteries without worrying about the effect of usage patterns on their life and they have lasted well (this laptop is 4 years old and the batteries still hold charge well). So it seems to me that starting with two batteries on a mac would be a good idea but I want to hear if there are relevant effects of usage patterns like this such that having two would gain nothing.
andy