Battery 9V

I've constructed a 12v battery out of 3V Lithium Coin Cell Batteries (CR3032). A stack of four 3V batteries would be 12V maximum charge, but my knowledge of batteries means this is actually a 9V Battery, as the minimum charge would be 9.3V thus for a 12V battery you would need a maximum charge of 15V. Every component within the battery has is there, feel free to learn from the model and use it in your own.