No More Cables? Does Wireless Charging Really Work?
We are ready for wireless charging but is wireless charging ready for us? As we discussed in our previous blog post, one of the hottest trends in phone technology is wireless charging, with many smartphones now automatically coming out of the box with wireless charging capability. The concept is simple – you place your phone on top of a charging pad, and it will charge for you even though it’s not plugged in.
While it sounds ideal, it’s important to remember that wireless charging is not a finished or advanced product yet, with much of the technology still in the development stages. Simply put, wireless charging is not as efficient or optimal as wired charging.
At Design Con, speaker Meng He said that he believes it will take another 10 years before the best wireless charging technology matures. For starters, wireless charging systems still require users to place their device in a specific spot, which in some ways could be less convenient than wired charging, especially with the presence of mobile charging stations.
For example, when the phone battery gets low, many people find it necessary to continue to work on their device even as it is charging. This task becomes much harder with wireless charging technology, as it typically has to remain flat and in place on the charging station. Rather than picking your phone up and moving it around as with a wired charging station, wireless chargers will need to keep the phone in place, lest it stop charging.
Additionally, wireless charging standards can vary widely, leading to issues with compatibility. In January 2015, two of the large wireless charging companies, Alliance for Wireless Power (A4WP) and Power Matters Alliance (PWA) merged, creating AirFuel Alliance. However, they each have their own standards, and they haven’t figured out how to make them work together. To wit:
- PMA relied on magnetic induction, depending on the alignment of a transmitter coil on a charging pad to connect with the receiving coil in the device. Often, you can find these in the Duracell Powermat that are commonly seen at Starbucks.
- A4WP uses a standard called Rezence, which uses magnetic resonance charging. While it also relies on the interplay of coils, it trades power transfer rates so that you don’t have to perfectly align the transmitter and receiver, like with the PMA standard.
- Perhaps the most popular standard is called Qi, which has been around since 2008.Like PMA, Qi uses an inductive system, and also added resonance charging to its spec last year, similar to Rezence. However, the kicker is that as of now, none of these standards are compatible with each other.
In short, if you’re on the go, using wireless charging and need to charge your phone, not only do you have to find somewhere capable of wireless charging, but it also has to be compatible with your device (unless you bring your own charging station along, which is often larger than a cord). Samsung has begun to support multiple standards, which may soon become the norm. However, IHS is forecasting that just 30 percent of the receiver market will support multiple standards by 2019.
The first Qi devices were about 60 percent efficient if you got them on the sweet spot, according to the Wireless Power Consortium, who is the creator of the Qi standard. The newest versions can be about 75 percent efficient. However, wired charging is about 85 percent efficient, meaning even the newest wireless charging stations have some catching up to do.
Wireless Power Consortium believes that they can match the efficiency of wired charging in time, as phones become designed differently and the Qi technology becomes more tightly integrated. While these wireless charging companies are aiming to develop dual systems that can combine the different technologies, it is clear that this will take some time to develop.
While wireless charging is a great idea, it’s important to understand that the technology is still developing. The lack of one reliable standard, coupled with a lack of efficiency when compared to wired charging make it clear that it is not a mature or finished product yet. At HGD, we’ve found that wired charging still proves to be the more efficient, cost-effective, and convenient option when compared with wireless charging. At least, for now. While many see wireless charging to be the wave of the future, it is clear that it is not yet the wave of the present.