To Qi or Not to Qi: Wireless Charging Laptops Introduction
NuCurrent has driven the wireless power industry for over a decade, launched more product categories into mass production than any other company in the world, and developed a global reputation for technology innovation with over 150 patents and countless contributions to global standards bodies like the WPC, Airfuel, and NFC. NuCurrent sets customers up for success in wirelessly charging laptops by posing five essential questions to determine which wireless power transfer method will be most effective for this use case.
While Qi-based (inductive) charging is the best-known method of wireless power transfer, there are several other options for product developers to consider. In the To Qi or Not To Qi: Wirelessly Charging Laptops Introduction video, NuCurrent explores and defines the different wireless power transfer methods available and details key terminology and concepts along the way.
Wireless Laptop Charger: What’s the Right Approach?
Choosing the right power transfer solution for wirelessly charging laptops such as HP, Lenovo, and MacBooks can be difficult. Due to the compact form factor and power needs higher than Qi’s current capabilities, wireless chargers for laptops will likely demand a custom design. In To Qi or Not To Qi: Wireless Charging Laptops, NuCurrent explores the most effective wireless power transfer solutions for a wireless charging laptop.
let's imagine sort of a standard 15-inch laptop
from somebody like HP.
Why don't you walk us through how you would advise someone
on which type of transfer method would be appropriate
for this type of product?
the first question I ask myself is
what is the power level required to power
or charge the device?
Laptops tend to, you know, be in the higher power range
between the 30 Watts to a 100 Watts.
They have specific load requirements to be able to,
you know, for example, charge a laptop
and allow it to function with a dead battery.
So you need to consider both a battery charger
and also a power source.
Based off that, you know, you can immediately eliminate RF,
which is, you know, on order of a couple of milliwatts.
NFC, which has a maximum power transfer capability
up to 3 Watts.
And the hybrid low frequency, high frequency, which is key,
you know, that's on the order of kilowatts.
So it's a little bit of overkill for this application.
So in my mind, this brings us to low-frequency technologies
and high-frequency technologies.
Both have the capabilities of supplying up to a 100 Watts.
So they are the right starting points
for a laptop in this example.
to the next question.
And we've got in our coding here, in our matrix,
you'll see N's equal no and Y's equals yes.
When we have a Y-plus, that means that there's something
uniquely advantageous to that particular method.
And when you see a Y-minus, there's something there
that might be a cause for concern.
Not a complete deal breaker
but something that you need to be aware of.
So in the second question, Jason, so do you need
to be interoperable with existing infrastructure?
you have to kind of look at the product.
So laptops are fairly commoditized.
You can go out on, you know, Amazon,
buy yourself a $300 laptop.
And you want to be able to charge it.
So when you start thinking about infrastructure
specifically for this type of product, you need to consider
that do you want to provide a charger
which will increase the overall cost of your product?
Or do you want to be able to use something
like infrastructure which allows people
to not have to purchase their own?
So from that standpoint, Xi low-frequency tends
to have the edge up on this as the fact that it's become
the global standard for wireless charging at this point.
You know, there are multiple tasks forces within Xi
that are trying to address the laptop market.
And trying to address the medium power market.
On the other hand, with high frequency,
you know, there is the airfield standard.
Unfortunately, back in 2017 when Apple decided
to go with Xi, the airfield standard just did not get
the same traction as Xi did.
So even though there might be possibility going forward
with an infrastructure, there's just no current development
or state that is at the same level that Xi currently gets.
So in this case, this is why I give a low-frequency Xi
a plus compared to high frequency
just because it is more built out
and more, let's say, widely adopted at this point.
won't work, it's just that if they want to go that route,
they're going to have to supply a charger in the box
along with it because there's no
universal charging capabilities.
So the next questions, Jason, three through four,
they're both tracking okay for low frequency
and high frequency.
Is there anything that you want to point out
about those questions with respect to this?
at the power levels we're looking at,
we'll more than likely have to go to a wire-rom technology
just to keep the resistance as low
at these higher power levels to ensure proper performance.
But looking at the general form factor of a laptop,
both high-frequency and low-frequency can have the space
to be able to integrate either a PCB or a wire-round coil
into the design.
So I gave both of these, you know,
kind of a level playing field, just due to the nature
of the design of the product.
With question four, what is the coil to coil distance?
And how many receivers need to charge?
High-frequency inherently lets you charge
at a larger distance.
But from a use case that you're looking for with laptops,
you know, when you're placing it on a desk,
you may have a pad, you may have something mounted
under the desk.
Both with the sizes of the coils that are possible
within the laptop, both of these technologies,
essentially are a level playing field.
High-frequency might have a little bit more spatial freedom
but at a cost of efficiency and potential EMI.
Low frequency, you might have to place your laptop
in a more fixed position.
But you would get the EMI and efficiency performance
that you're looking for.
So in this case, I give them both kind of a equal
on this question.
And then for the final question,
does the power need data transfer capabilities
greater than 10 kilobits a second?
Usually, the wireless power is not going to be used
as a data channel.
Laptops obviously have lots of different radios
and functionality through USB, and wifi, and Bluetooth.
So in this case, it's not really needed.
And that's kind of the last question here.
And why both low frequency and high frequency
are on the same level playing field.
this is really a (mumbles) option for laptops.
Which, you know, if you want to pursue
this type of product development,
Xi is a really strong candidate.
And of course, Nucurrents Nueva,
low-frequency development platform is there
for getting you to market quickly
while eliminating a lot of these risks that are,
that come with wireless charging development.
(upbeat music)
Is Qi Charing for Laptops the Way to Go?
Qi-based (inductive) charging is the most popular form of wireless power, and for good reason. But there are many more power transfer methods to consider when deciding which is best for your device.
In this 60-minute session, NuCurrent will look into the different wireless power transfer methods available and walk through the tradeoffs that come with each method, followed by a recorded Q&A session.