Fuji GX680 USB-C Battery Replacement Box with 2x 18650 and BMS

This is, in my opinion, the best and cheapest way to modernize your GX680. Battery life has been great with two 18650 cells and the build is relatively simple. All the parts are available on Aliexpress.

This is a remix of futtigue's brilliant AA battery box for the Fuji GX680. What I did was model a housing on top, add cable channels and mounting holes for a BMS/charging board and I modified the spring tension since it was a bit too soft for my camera.

To build this, use double sided tape to mount all the parts and optionally add some screws on the USB-C board. The metal contacts get screwed down with some plastic/wood screws as well, while the 18650 holder and the housing get mounted with M3 screws and heat press inserts.

All you need to print is the housing and lid. The f3z file is just there in case someone wants/needs to make any modifications.

Parts I used:

• cheap AAA/AAAA battery contacts (screenshot in photos)
• IP2326 USB-C charging board
• HX-2S-JH20 2s BMS
• 2x 18650 SMT battery holder
• some wires
• printed parts
• M3 threaded inserts
• 4x ~15mm countersunk M3 screws (housing)
• 2x ~5mm socket cap M3 screws (18650 holder)
• 4x generic screws for in plastic, up to 5mm length. Hole diameter is 1mm, so use a slightly larger screw. Head needs to be reasonably small (this is to secure the AAA battery contacts). I just cut some screws down I had laying around. I also used two of these to hold down the USB-C board, but the threads had to be cut down a lot of course.

optional:

• red LED + resistor for the external charge LED

Don't take my part choices or wiring as the best solution. Everything is provided without any liability and you're responsible if it blows up. Batteries are dangerous :)

Please let me know if you have any questions or comments. Also, post a make if you built one! It'd make me very happy :)