It doesn't matter if you want to build your own electric car, if you work with grid battery storage or even if you work for a power supplier in finance for the energy sector:

Understanding key engineering concepts will pay off in the long run, so I made this video to break down a complex concept with simple animations for you.

If you don't understand series and parallel layouts you might order wrong lithium batteries, destroy expensive equipment or mis-arrange lithium cells. Mis-arranging cells can cost you when undercharging cells or put capital and life at risk when overcharging and creating a fire.

But don't worry, it is important, but not too complicated, arrange a battery pack below with the sliders and watch the video where I go over it in detail and it will become clear fast!

This video is about the series & parallel connections in a typical battery pack in a car or as off-grid storage near a solar installation or even for a residential home.

Also, a Battery Management System is key to keeping your batteries safe. You must not charge them higher than 4.2V (4.15V really), and must not discharge them lower than as an absolute maximum to 3V or you damage your cells or risk a fire. I mention this at the end here, but you should watch the BMS/ Battery Management System video separately from this.