Technical article: Two factors preventing wireless charging from becoming mainstream

By: Mark Hopgood, Dialog Semiconductor, Neeraj Sahejpal, Energous

We live in an extremely mobile, yet physically tethered world. From smartphones, smartwatches, fitness trackers, Bluetooth headphones, hearing aids, and other wearables or hearables, many of us are outfitted from head to toe with mobile devices.

But these mobile devices need to be charged, and they need to be charged frequently. Depending on how often we use them and what we use them for, these devices may even need to be charged several times a day. This means that we always have to carry a charger with us wherever we go, or that chargers are available wherever we go.

This is why we say that the mobile range of electronic devices is limited by the length of the charging cable. This also makes wireless charging an inevitable development trend.

Wireless charging is a pretty obvious solution to the charging woes we face every day. Which raises the question: What’s holding wireless charging back from going mainstream?

There are two factors here: one is practical, and the other is ideological.

Design barriers

The first practical factor is the design itself.

The design challenges of wireless charging vary from device to device. For larger devices, such as mobile phones, the challenges include charging efficiency and how the freedom of movement of the device (user) affects the wireless charging process. For smaller devices, such as hearing aids and smart ear-hearable devices, the design challenges include the placement and orientation of the device during the wireless charging process, which is a problem for more traditional coil-based wireless charging solutions.

Another challenge is the size of the wireless charging solution itself. After all, the coil is not very small in size. This brings another level of difficulty to the design of the device. How to make room for a large coil in a small device?

In order to meet the needs of wireless charging, engineers need to refer to several indicators:

• Is there any freedom in the orientation of the equipment?

• Is there flexibility?

• Is the charging mechanism efficient?

• Does the device need to be placed in a very precise position to charge?

There are a lot of conditions to meet here, but this challenge is actually solvable.

One solution that can solve all of the above challenges at once is WattUp technology from Energous, an RF-based wireless charging solution that works similarly to Wi-Fi.

Changing cultural perceptions

The biggest hurdle to wireless charging isn’t design difficulty. Engineers can always find a way, and they are working on it. Rather, the biggest challenge is user perception and the need to answer the inevitable question consumers will ask: What does wireless charging have to do with me?

Think about the major technological achievements of the past few decades: computers, the Internet, cell phones, smartphones, iPods, etc. Before these products appeared on the market, did the public clamor for these products? For most people, the answer is no. Because people don’t know what they want until they know it or see it in person. The same is true for wireless charging: most people don’t know they want wireless charging, or what benefits wireless charging will bring to them, because the public has not been exposed to this concept. Only when the public’s concept changes can wireless charging truly become mainstream.

A world without chargers

Imagine a future where you don’t need to carry a charger with you everywhere you go, you only need to carry your device.

Wireless charging sensors can be installed in various rooms of the home, on desks, on phones in conference rooms, at local coffee shops or convenience stores, movie theaters, train stations, bus stops, airports, etc.

In other words, every place you go with Wi-Fi could have a wireless charging sensor that automatically detects your device (if it comes within range) and charges it from a distance.

Wireless charging is a win-win technology. For device manufacturers, they can ensure that customers can obtain data without interruption during use, thus providing a better user experience. After all, suppliers of health wearable devices do not want consumers to need to take off their devices for charging, resulting in interruptions in obtaining health data. For consumers, they no longer need to worry about running out of battery and where to find a charger nearby.