Wireless energy transfer methods and designs for implantable electronics and devices include, in at least one aspect, a device resonator configured to be included in an implantable medical device and supply power for a load of the implantable medical device by receiving wirelessly transferred power from a source resonator coupled with a power source; temperature sensors positioned to measure temperatures of the device resonator at different locations; a tunable component coupled to the device resonator; and control circuitry configured and arranged to adjust the tunable component to detune the device resonator in response to a measurement from at least one of the temperature sensors.