After an initial 10 years spent on charging the battery of mobile phones, the WPC (Wireless Power Consortium) is looking to expend their technology to objects embedding bigger batteries. Unfortunately, a bigger battery means, at equal power transmitted, a longer loading time which is in most cases a no go.
Therefore, the WPC has decided to open new research groups, targeting devices such as laptops, power tools, tooth brushes, rice cookers, or deep fryers. It is easy to understand that powering up a deep fryer would require different means than powering up a mobile phone (coils, components to generate this additional power, …). Therefore the WPC has decided to create power classes, to make sure not to make the system and test specifications unnecessary complicated.
Which power classes are in place?
As of December 2017, we have:
- Power class 0: this is the legacy technology. It’s used to load the battery of devices such as mobile phones, tablets, and small accessories. It has a maximum transmission power of 15W. It is split into 2 profiles:
– BPP (Baseline power profile): this is the legacy of the legacy (development started in 2008) and allows transmission of power up to 5W. This is the one used for the iPhone 8 and X for example.
– EPP (Extended power profile): it is an extension of the BPP technology, allowing to transfer up to 15W.
- Power class 1: this is a still new, but very active area of research for the WPC. This one will allow to transfer up to 200W. It will therefore potentially be used with laptops, personal care devices, power tools, and drones. It is split in 2 sub groups :
– battery : this one will service simpler devices, such as power tools. This is the one which is making the most progress as of now (compared to the laptop group) with simpler requirement. This sub group is led by Bosch
– laptop : this one will service….laptops! It is led by Apple, NXP, Lenovo. The use case definition is still a bit vague, but keep in mind it is coming.
- Power class 2 (aka kitchen) : aiming at transferring more than 200W. The power class 2 will serve devices that are generally demanding in terms of power, such as rice cookers. It is led currently by Philips and companies like De Longhi and Haier are considering this.
Micropross currently serves the power class 0, with a coverage for both EPP and BPP power classes.