New MB... Are My Old Chargers Useless

Hi, i've just got a new MB.

My old MB is 4 years old and i've managed to build up 3 chargers (work, home, travel bag) for it over the last few years.


My Old MB uses: 85W Magsafe Power Adaptor

My New MB uses: 45W Magsafe 2 Power Adaptor


Can i use my old 85W Magsafe Power Adaptor on my new MB or will it harm the battery?

Apple state you should use the unit that comes with the MB, however 85W chargers should not hurt it. Personally I do not think I would:-


https://support.apple.com/en-au/HT201700

The Magsafe will not fit in a Magsafe 2 port.

There is an adapter available.

You can use a higher powered connector, but not a lower powered one per Apple - link.

Apple has a Magsafe->Magsafe2 adapter.

Thanks guys, i think it should be fine, as it will only use what it needs

my mba's been charging on 85w adapters (with adapters) mostly since I got it. There's no issues, you're correct, the hardware is designed to not allow over charging. Mostly this is so things like Apple Monitors can charge mobiles.

For what it's worth, you can also charge a MBP with a 65w adapter. It'll run fine, as long as there is some battery. If not, if it goes over 65w of usage it'll drop. It'll also take a while before you can power the system on.