Over the past 5 years, wireless charging speeds in a handful of telephones have risen from around 5 watts to 1
Why are wireless chargers so far behind the curve? Well, it appears that it is difficult to make wireless chargers powerful without making them unsafe.
First, let's see how wireless charging works.
Wireless chargers send power to your phone through magnetic induction and magnetic resonance. Or, in layman terms, wireless chargers extract electricity from your outlet, run it around a coil and generate a magnetic field. This magnetic field works in conjunction with a coil in your phone to generate an electrical current, with which your phone charges the battery.
Simple, right? Let's go a little deeper. Faraday's induction law states that an electric field will always generate a magnetic field and vice versa. This means that all electronics, including light bulbs, emit a magnetic field. Unfortunately, a light bulb cannot charge your phone because your phone is built to work only with magnetic fields with a specified speed and intensity.
This specified speed and intensity are usually described as a "standard". Modern telephones are made to support various standards, such as the Qi standard for wireless charging. Each wireless charging standard supports different charging speeds, so Samsung phones with specialized spools can take advantage of 15-watt wireless charging, while limiting other devices at lower speeds.
Okay, now that we know the way of a lot about about wireless charging and magnetic fields, we can finally approach the big question: why are wireless chargers still so slow?
Wireless chargers can be faster, but they fry your phone
Let's get to the heart of things. Wireless chargers can charge your phone much faster than now. But today's wireless charging hardware is not efficient enough to safely charge your phone at high speeds. Just like the wasteful light bulbs of the past, wireless chargers produce too much heat.
You have probably experienced this personally. Even with the refined low wattage Qi standard, telephones heat up during wireless charging. And, as we all know, excess heat can damage hardware and lead to empty, swollen or exploding batteries. Strengthening the power of our inefficient wireless chargers would simply not be safe.
Okay, but how far are we from a safe, powerful wireless charger? If the new 15-watt wireless technology is an indication, we are now heading in that direction. According to a Digi-Key article, wireless chargers still waste between 20% and 70% of the electricity they use. Samsung may have found a way to make its technology more efficient than the competition, but they need to go even further if they want to achieve half of the wired charging speeds of their latest devices.
Even with more efficient wireless chargers, manufacturers are still faced with some limitations. Precision is an immediate example. You may have noticed that some wireless chargers refuse to work when pieces of metal, such as keys or pocket money, are too close to the loading surface. This is actually a safety measure, because intense magnetic fields can heat metal objects. As wireless chargers become more powerful, manufacturers must develop better algorithms for detecting foreign objects or limit the working distance of their fast-loading mats.
In short, wireless chargers don't get faster until technicians and manufacturers find a way to make them energy efficient and accurate. This may mean that we are leaving the Qi standard, or using new hardware that makes better use of what we have now.
We must also recognize that the loading distance may be a more direct concern than the loading speed. For example, if a phone can charge within 10 meters of a wireless charger, it doesn't really matter how fast it gets to 100%. Hopefully, manufacturers will find a way to increase the range of wireless chargers and . But in the meantime, we recommend keeping a real cable at home.