Battery Designer This is the best battery design software on the planet. With this program, you can generate STL files for the cell holders, case, and much more. Box Generator This is a tool to instantly make boxes of all shapes and sizes. Render Room This is a program to arrange and showcase STL files. Custom Case Tool Article · Battery Designer There is now a custom case tool. You can get to it by going to  Settings --> Parameters --> Frame Type and choosing 'custom' from the drop down menu.  Currently, th Low Cost 200W Inverter Article · Home Energy A defense of a tiny, inexpensive car inverter: not pure sine wave, but still a smart buy for small loads, portable setups, and cheap DIY power.