to be the king of flashlights, but replacing those pesky D-cell batteries is kind of ridiculous in this day and age. So [Travis] decided to upgrade it to make use of the ever-so-common ...

At 900 cycles, 18650 batteries made with Novacium’s GEN3 silicon-based anode materials are still delivering more than 3,100 ...

The same holds true for battery power. [Andreas] wanted to use protected 18650 cells, but didn’t want to buy them off the shelf. He found a forty cent solution. Not only can you see it in the ...