Battery is very common in our daily life. It brought a great convenience for today’s smart home life. However, sometimes when I got a lithium battery but I don’t know whether it needs to be recharged, this bothers me a lot. If there is a thing that can help me to monitor the battery’s capacity, that would be great! As a zealot of maker, I certainly would not miss any chance to DIY cool stuff. OK, let’s get start.  

 (The shiny dice idea is from a drama I recently watched---Killing the Immortals. You can design your own style. In addition, there is no need to install any batteries on the circuit board as it can be powered by the lithium battery that is going to be tested.)

The materials you may need:

Operation:

Step1. Print out the case through 3D printing, and drill several holes in the case.

Step 2. Add green metal complex dyes into the Crystal Epoxy Resin several times to make a sense of hierarchy of gradual change, and the bubbles produced during the process can be retained as decoration.

Step 3. Solder the LED Lamp Beads on the flexible PCB and assemble the circuit board.

The program is omitted here. This is my work.

After plugging in the lithium battery, this special dice will measure the percent of the battery’s capacity. If the capacity is above 80%, the dice will light up in the sequence of 1, 2, 3, 4, 5, 6. There’s a 400ms pause between the on-state of two sides’ lights. All sides’ lamp beads of the dice will be on if there is enough power in the battery. If only the 6th side is off, it represents that there is 60%-79% capacity in the battery. The 6th and 5th off... 40%-59%. If only the first side is on, the battery needs to be recharged.