“A self powered 18650 Lithium-Ion battery discharge board.
When I designed and tested a Li-ion charging circuit I needed a discharged Li-ion cell and so I grabbed a few power resistors and from time to time I measured the voltage because I did not want to discharge it to deep, otherwise the battery may get damaged. But the risk is high that one day I forget it completely. I needed a simple self powered discharge tool, not an electronic load that requires setting up from a computer or something. In this project I am designing a simple and cheap 18650 battery discharge tool that discharges until 2.45V and then releases the load so that the voltage can recover to about 2.85V. The smart thing is that I use super cheap DW01 and FS8205 li-ion protection circuit that is present in so many battery protection boards to do the voltage cut out and release. This project logs all my designs decisions, testing, mistakes and redesigns. Now I consider the project finished. The BOM cost is only 1.70 euro. I plan to sell it on Tindie as a kit.”