Check out my fingernail size home made drycell powering a wall clock. The basic design is all based on my original water battery. But now no water needed, and can be made much smaller. Here is the link to the video https://www.youtube.com/watch?v=C5s1kHpbKj0 (https://www.youtube.com/watch?v=C5s1kHpbKj0)
Overall, these are what I'm following so I want to know if you can recommend me.