Update 9-5-2020: There is a new model which includes a battery status indicator here:

https://www.thingiverse.com/thing:4588442 This is a collection of battery and battery charger holders for the Black and Decker 20V MAX Batteries (both regular size and extended 5.0Ah batteries). These models have the following features: * Models for Extended 20V batteries. * Mounting holes to use with #8 screws (non pegboard versions). * Versions for mounting on 1" peg board (with pegs which you can optionally use #6 x 1/2" or M3 screws to better secure the holder into the peg) * Versions with a clip for storing the charger. * Charger storage versions have built in cable management guides. * Holes in the bottom of the holders for possibly better airflow (my extended batteries have vents in this area). To determine which file you need, the files are named according to the options they include, for example: BD-20V-Battery_Holder_V38_REG_CHARGER_PEG.stl REG = Regular Size Battery EXT = Extended Size Battery CHARGER = (yes or no) has a clip for holding the charger PEG = (yes or no) mounts on a 1" peg board If not using the pegboard mounts use #8 screws for mounting. For a more secure mounting on the pegboard, you can optionally install #6 x 1/2" or M3 x10mm screws in the holes which go through the pegs. Note that it is possible you could damage the holes in your pegboard by screwing the holders down through the pins. I have installed and removed these without damage to my pegboard after using the #6 screws to lock the pins in place, but I was careful to work them out when removing. If concerned, you may want to try testing the pegboard pins with screws in an obscure location first with the screws you plan to use and try M3 screws instead of the #6 screws which are a bit larger - or omit the screws all together. If you are just needing a charger holder, I made one you can find here: https://www.thingiverse.com/thing:4552501 The STEP file is included for easy remixing. Parts are not oriented for printing, but I suggest printing them in the tall orientation (same way they would be mounted on the wall). Supports are required for the pegboard versions.

Found 2 3D-models for “50AH” across many websites

Phantom 2 custom battery (5.0AH) cover

Black & Decker 20V MAX Regular or Extended 5.0Ah Battery AND Charger Holders (with 1" pegboard mounting option)