Best way to identify items with NFC tags and Photon

I am planning a home automation project that locates objects in a closet. I will have multiple shelves, and each one will have eight NFC tags and eight LEDs, each connected to a Photon. I will store plastic storage bins on top of the tags. I will be able to use an app on my phone to illuminate the LED above the bin I am looking for. However, I do not want to have to put the bins back in the same place every time. I was wondering - what is the best way to detect small NFC/RFID chips with a Photon and determine which bin it is? I would have a name assigned to each bin. Thank you.

You could put a NFC reader under each bin location however that might be a bit expensive. What about a single NFC reader near the closet and either pressure switches or just pushbutton switches under each bin bay. Here’s how I imagine it working:

  1. You remove a bin.
  2. You go to put the bin back (anywhere you want). You tap it against the reader which reads the bin’s #
  3. You place the bin back anywhere you want. The Photon records which bin location is now occupied. It pulls the last bin # read and updates the bin bay # to bin # table/relationship.

If you really want to do NFC then are several NFC “shields” with integrated antenna or some (i.e. Seeed/Grove) that have remote antenna on a short (2-3 inch) leader. The readers are fixed to each location and the tags attached to each bin. These are on SPI so you would have to place the Photon close (inches) to its respective sensor.

Agree with @harrisonhjones that NFC readers at each bin location will get spendy fast (NFC tokens/tags/stickers are cheap… readers not so… plus most are i2c/spi so 1 or 2 per photon). Not so techie solution could be to use coded bins with a small square of conductive aluminum tape in each corner of the bin’s bottom (3 squares needed to identify an Empty spot or bin 1-7). The shelves would have corresponding probes to register bins (short or open via conductive tape) placed on them. Then you can sweep all spots with one photon.