When it comes to wireless charging, most people may first think of the Qi standard. Qi wireless charging has been around for a long time and is widely used in many of the smart devices we use every day. However, many small electronic devices do not support Qi wireless charging because there is not enough room inside the small device for a large coil to receive enough power. In response to this challenge, the Near Field Communications (NFC) industry association previously created the NFC Wireless Charging (WLC) specification.
NFC wireless charging was announced in May 2020, and the antenna size it uses is much smaller than Qi wireless charging. NFC wireless charging antennas can be less than 1cm in size and packaged in flexible and bendable printed circuit boards, so they can be stuffed into very small smart devices like headphones, styluses, smartwatches and trackers. Additionally, the same antenna can be used for traditional NFC data transmission, saving even more space. Many small, low-power devices such as trackers already contain NFC chips for basic data transfer, so replacing them with a single antenna for communication and charging would be very practical.
Despite being announced nearly four years ago, NFC wireless charging technology hasn’t seen much penetration. One of the reasons for this could be the lack of support for mainstream operating system platforms like Android. However, the upcoming Android 15 is gearing up to add support for NFC wireless charging, which could pave the way for a range of WLC-enabled accessories to hit the market.
Last week Google released Android 15 Beta 1, which significantly changed the operating system’s NFC module. For example, system apps that handle NFC-related events now include a class called NfcCharging that can start and stop NFC charging, read the charging information payload sent over NFC, and more.
Android 15 Beta 1 also includes new features of the operating system NFC API related to WLC that are not yet available in AOSP. Interestingly, Google first attempted to add WLC support in late 2021, nearly a year and a half after the WLC specification was first released, but later abandoned the effort. However, earlier this year, Google seemed to have renewed interest in implementing WLC support in Android.
An interesting application for NFC wireless charging is in trackers. Trackers are often too small to accommodate Qi wireless charging coils, their batteries are also small and don’t require much power to fully charge (WLC can send up to 1W of power at a distance of 2cm), and they already have an integrated NFC chip. While many trackers boast up to a year of battery life, some use non-rechargeable batteries. With integrated NFC wireless charging support, future trackers will be even easier to maintain and charge.
Another potential use case is charging a stylus. In fact, the USI 2.0 specification has NFC wireless charging built-in, so USI 2.0 styluses on the market can already be charged via NFC. But charging them still requires a compatible device that contains an NFC charging transmitter.
Once NFC wireless charging support is integrated into Android, wireless charging will become more common and applicable to small devices such as headphones, styluses, smartwatches, and trackers.
