Near-field communication (NFC) is often looked for as a spec in mobile devices and wearables, as it is often necessary to support the kind of quick, convenient pairing with which it is often associated, not to mention payments. However, it is also emerging as a charging option, and might indeed prove handy for wearables and some accessories (particularly styli) in the future.
NFC charging is thus touted by its proponents as an efficient, effective and potentially always-on way to power smaller electronics that might have to operate in awkward or cramped conditions. In fact, it is already in use by those who use the WHOOP ecosystem of health- and exercise-monitoring wearables.
These products, particularly the newer versions, incorporate NuCurrent's NFC wireless charging tech, as it is rated to keep the devices in question on all the time and, thus, continually tracking the user's training or condition data.
It adheres to the NFC Forum's wireless charging (or NFC WLC) specification, which allows for charging at 0.1 to 1 watts (W), while transferring data at up to 106 kilobytes per second (kb/s). However, NuCurrent claims to have exceeded both criteria in its upgrade for the WHOOP 4.0 system.
It involves a charging rate of 1.2W, with a bidirectional data transfer rate of 424kb/s. Furthermore, the latest NuCurrent NFC tech eliminates the need for copper contacts in this generation, meaning the resulting battery pack can claim an IP68 ingress-protection rating, as well as relaxed size constraints that means the user can still get up to 5 days' worth of battery life with a pack 33% smaller than that of WHOOP 3.0.
NuCurrent has also recently showcased a different prototype with specs of up to 3W and 848 kb/s. Therefore, NFC for charging might get more common and useful as time goes on.