Apple produces its own MagSafe accessories, but they also released a accessory design guide that details the types and magnetization directions of neodymium magnets that accessory manufacturers can use, as well as other design details that Apple requires. Therefore, the third-party manufacturers can also design MagSafe accessories according to this accessory design guide.
What Wireless Charging Magnet is Used in MagSafe?
In accessory design guide, Apple uses strong but with high temperature resistance Magnets
Considering the heat generated during charging, the magnet needs to be able to withstand high temperatures. At the same time, due to the size of the MagSafe case, it is necessary to use a magnet as small and thin as possible, and the magnetic pull force is large enough. To sum up, there are three points: high temperature resistance, small size, and large magnetic force.
The only known magnet material that can meet this requirement is neodymium iron boron magnet. Therefore, Apple chose the strong neodymium magnet with grade N45SH and coating NiCuNi (7 µm – 13 µm) on MagSafe case, and with grade N48H on MagSafe accessory. MagSafe accessory magnets don’t need to withstand as high temperatures as MagSafe case magnets. So their magnet grades are different. If you want to know more about grade specification, please visit neodymium magnet grade table.
It’s hard to make a super thin wall ring by neodymium magnet because magnet material are very brittle. Segment magnets are a good solution for this application. There are 36pcs arc magnets in Apple MagSafe case. They are very thin and glue to case by adhesive without destroy the integrity of the appearance. At present, there are various small and thin segment magnets with different sizes on the market for magnetic wireless charging devices.
N45SH Industrial Neodymium – Heat Resistant Magnets
Usually, daily-life items use more affordable N series neodymium magnets, such as N35, N42, N45, N52 and etc. However, these two grade magnet materials N45SH and N48H, especially the former, it is a industrial magnet commonly used in various motors and generators. It is a relatively high-end magnet material, So the price is more expensive. This may be one of the reasons why Magsafe is not cheap.
There is an argument whether Apple is wasting resources by using high-end neodymium iron boron in charging devices. But Apple stated on its official website that iPhone 12 uses 100% recycled rare earth elements in all magnets, including those in their MagSafe accessories, as part of a stepped up environmental initiative which also has geopolitical implications.