“The rate limiting factor [in wireless charging] is not antennas but the battery circuit itself,” NuCurrent CEO Jacob Babcock told EE Times.
Babcock explained that a recharge cycle might miss a full charge by several watts if the battery gets too hot. In addition, the current will only flow around the outer edge of the wire causing longer charge times.
“NuCurrent invented the ML wire -- it’s like bundling 100 drinking straws together to pass through liquid -- then we optimized conductive area available based on skin depth of a frequency. We’re able to pass more current with lower resistance through that wire,” Babcock said.
NuCurrent produces multi-mode antennas for wireless charging. Its antennas can support Qi, Power Matters Association (PMA), and Association for Wireless Power (A4WP) standards, which all operate at different frequencies. Thus it must manage several skin temperature possibilities.