PowerBook AC Adapters, what's the difference?

[BeoVir]

Ok so I have a 12" PBook with a 45watt AC adapter. I have a friend with a 12" iBook and a 45watt adapter, another has a 15" TiPBook and a 65Watt charger.
My Kensington car/airplane adapter outputs a continuos 75watts. I am curious as to why they are at different values.

As stated in this the power adapters can have problems supplying enough charge at a lower wattage and I assume if too high a wattage that the battery and circuitry can be harmed.

I would like to know why Apple would use different values and also if I can use a 65watt power adapter instead of the stock 45watt adapter to charge my laptop faster. I think I can as the car charger is at 75 but I want to be sure. Thanks.

 

[superbovine]

My guess is heat and price. the power bricks are very small and output a lot of heat. any higher wattage would to much heat for that size or the powerbrick would have to be bigger. The kensignton 75 w which i have, is longer and thus can handle heat better. also the kensignton is actually the same adaptor that targus sells for pc laptops so it was designed to handle a multitude of laptops vs the powerbrick which was to handle only a few notebooks.

Ok so I have a 12" PBook with a 45watt AC adapter. I have a friend with a 12" iBook and a 45watt adapter, another has a 15" TiPBook and a 65Watt charger.
My Kensington car/airplane adapter outputs a continuos 75watts. I am curious as to why they are at different values.

As stated in this the power adapters can have problems supplying enough charge at a lower wattage and I assume if too high a wattage that the battery and circuitry can be harmed.

I would like to know why Apple would use different values and also if I can use a 65watt power adapter instead of the stock 45watt adapter to charge my laptop faster. I think I can as the car charger is at 75 but I want to be sure. Thanks.

https://forums.macrumors.com/threads/93065/[/URL

 

[bellis1]

Power problems

I heard that Apple is no longer even making the 45W adapters and now everything is the higher wattage (65W?). I had a 17" PB and was using an iGo charger that you could use in your car, airplane, etc. And it usually would work well but sometimes it just would not give it enough juice to charge and the computer would just stay at the same charge (and eventually decline). I was in a foreign country with intermittent power problems but it was very annoying because even re-setting the power manager would not work. The computer would only start charging again once I got to a 65W charger. A real pain and iGo should have given me my money back. They now make a higher wattage charger but I don't think it can connect to a car.

 

[diamond geezer]

Apple only produce the 65W adapter now.