Q factor for ST25DV

[bobbyjames]

I’m designing a tag coil for the ST25DV-04k. I am planning to use the ST25 to harvest NFC energy from a phone tap for a bioimpedance sensor (MAX30002). The ST25DV will then relay the sensor measurement to the phone via NFC again. I used an online calculator to design the tag coil, and these were the parameters I chose. 

Parameters for tag coil

However, I am unsure if my quality factor is too high. “59.77” is before coupling, and I assume it will be lower after that. I understand that a high Q is great for energy harvesting, but it can limit the bandwidth and garble communication between the tag and the reader.

Is my Q too high right now? If so, what is the optimal Q factor range? 

Anything else that stands out from my coil design?

[db16122]

UM2042 User manual Discovery kit for the ST25R3911B high performance HF reader / NFC initiator