Guest post by Dalibor
First thing to do was to make a frame. Then add layers of fiberglass. Filling the voids and irregularities with git and then the painting.
![Cutting a side opening and making a lid](https://bike.bikegremlin.com/wp-content/uploads/2020/06/01-rezanje-bocnog-poklopca.jpg)
![Laying of fiberglass fibres](https://bike.bikegremlin.com/wp-content/uploads/2020/06/02-vlakna-fiberglasa.jpg)
![Covering irregularities with git, before sanding and painting](https://bike.bikegremlin.com/wp-content/uploads/2020/06/03-spricgit.jpg)
I opted for the black colour:
![Finished electric bicycle battery housing](https://bike.bikegremlin.com/wp-content/uploads/2020/06/04-finished-electric-bicycle-battery-housing.jpg)
![Finished electric bicycle battery housing](https://bike.bikegremlin.com/wp-content/uploads/2020/06/05-finished-electric-bicycle-battery-housing.jpg)
![Finished electric bicycle battery housing](https://bike.bikegremlin.com/wp-content/uploads/2020/06/06-finished-electric-bicycle-battery-housing.jpg)
Housing holds all the batteries, wires, connections and a display that shows battery state, consumption and other parameters. It also has a contact lock with three switches and a jack for battery charging. Switches are used to turn on the display, speed limit and cruise control.
![Side view of the electric bicycle battery housing](https://bike.bikegremlin.com/wp-content/uploads/2020/06/07-electric-bicycle-battery-housing-side-view.jpg)
![Battery housing mounted on an electric bicycle](https://bike.bikegremlin.com/wp-content/uploads/2020/06/08-battery-housing-mounted-on-electric-bicycle.jpg)
Photo gallery of the finished project of Polar Viper electric bicycle modification.