Headway 38120 20cell battery tray

I was in need of a custom battery tray for 20 Headway 38120 LifePo4 cells and a balance board. This design allows you to install 20 cells and configure them in any manor you desire. I used this setup for a 4s5p battery arrangement.
My battery was made with an upper and lower tray, 6 battery tray braces and 1 balancer board mount.
The 4s balance board is a generic flying capacitor 5amp discharge balancer design.
https://www.amazon.com/dp/B09G74WDN5?psc=1&ref=ppx_yo2ov_dt_b_product_details

The Headway cells I purchased from BatteryHookup.com
https://batteryhookup.com/products/used-headway-38120-hp-3-2v-8ah-lifepo4-battery

The trays will except a Headway 38120 by pressing them into the openings. They will have a nice friction fit. You can also add the battery tray braces to give the upper and lower trays more support. These can be attached with either #12 or ¼" allen screws.

You will need to connect the busbars on the backside of the trays in the configuration of your choice.

Due to this design being able to be used in multiple different configurations you will need to drill your own mounting holes for the balance board. The balance board mount is for the 4s balancer linked above. This board can be secured to the mount with M3 screws. If you choose to use a different balance board you will need to design your own mount.

I printed all items out of PETG with my standard settings.

08/15/23 Added busbar dril guides if you want to make your own busbars for a 4s5p configuration. 
You you want to do the 4s5p setup you will need:

• 2 - 1.5 inch x 8 inch x ¼ inch or thicker aluminum. 

• 3 - 2.5 inch x 8 inch x ¼ inch or thicker aluminum.

Place the bars inside the drill guide and drill all holes with either a 15/64 drill or 6mm drill bit. This will give you enough clearance for the 6mm bolts to pass through the busbar into the cells. The guide is designed for a 6mm bit but those with only fractional bits will find a 15/64 bit will work fine. A 15/64 bit is only .002 inch smaller than the 6mm bit.

09/27/26 - Updating the installation of the audio system this battery tray was originally designed for. The new layout requires a different configuration of the cells. As such the mounts have been changed to accommodate the new cell orientation.

Materials needed:

 1/4 inch threaded rod for the tension bolts.
8 - 1/4 inch acorn nuts (same thread pitch as the rod)
20 - 1/4 inch nuts (same thread pitch as the rod) (Not needed if using the batt_spcrs print)
24 - 1/4 inch flat washers (If using the batt_spcrs reduce count to 8)
24 - 1/4 inch lock washers (If using the batt_spcrs reduce count to 8)
2 - 1/4 inch aluminum plates 3inch x 5.25inch long

To assemble:

Print 
1 - +_batt_end_cap
1 - -_batt_end_cap
2 - batt_cntr_cap

Optional:
12 - bat_spcr (used to cover the threaded rod and give a cleaner appearance)

Insert cells through the center holders.
Insert aluminum buss bar into each end cap.
Secure end caps to cells with appropriate M6 hardware
Pass threaded rod through all cell holders and secure them in place.
Place a flat washer against the each face of the plastic cell holder, followed by a lock wasker and lastly a 1/4 inch nut. 
Optionally: If using the batt_spcr pass a spacer over the threaded rod between each cell holder and omit all 1/4 inch hardware, exception for the end caps.
Secure the threaded rod at each end cap by placing a flat washer, followed by a lock wash and lastly an acorn nut.