Mag-Lite 2-Cell C Size Adapter for 18650 Lithium Batteries

thingiverse

For this adapter, you will need to machine the front and rear spacers from aluminum or brass according to the drawing specifications.\r\n\r\nThe two C cell alkaline batteries are replaced by one 18650 button top lithium battery. I have used an unprotected type. The 18650 provides 3.7 volts compared to three volts from two C cell alkaline batteries. I am currently using a 4.5-volt Mag-Lite bulb which works quite well, but I intend to replace it with a LED bulb. LED bulbs are available on eBay and are expected to be the preferred choice.\r\n\r\nThe following video explains the design, demonstrates assembly and installation into the Mag-Lite flashlight. https://youtu.be/6BcD2K7EjpE\r\n\r\nThe 3D printed adapter holds the battery and spacers in the correct position and acts as an insulating sleeve. The adapter, with front and rear spacers, provides positive contact with the Mag-Lite switch contact and the tail cap spring.\r\n\r\nC cell alkaline batteries are rated at 8000mAh. Alkaline batteries are expensive, tend to be unreliable and are known to leak, which can ruin your flashlight.\r\n\r\nThe single 18650 battery is rated at 3000mAh. It will last longer than C cell alkaline batteries when running a LED bulb and I expect the 18650 will hold its charge (unused, sitting on the shelf) six months or longer.\r\n\r\nI have designed adapters for two C, three D and two D Mag-Lite Flashlights. The three C and three D adapters hold two 18650 batteries. To avoid confusion, each adapter is listed separately on Thingiverse.\r\n\r\nOther available Mag-Lite adapters include:\r\n\r\nMag-Lite 2-Cell D Size Adapter for 18650 Lithium Batteries\r\nhttps://www.thingiverse.com/thing:3473302/edit\r\n\r\nMag-Lite 3-Cell C Size Adapter for 18650 Lithium Batteries\r\nhttps://www.thingiverse.com/thing:3473408/edit\r\n\r\nMag-Lite 3-Cell D Size Adapter for 18650 Lithium Batteries\r\nhttps://www.thingiverse.com/thing:3473442/edit