What are the pros and cons of these configurations? Assuming the light is identical otherwise, which configuration would you choose and why?
21700 I guess :
- the diameter is not much larger with 3x21700, 45.4 vs 43.5mm, the additional length doesn’t mater too much for a soda can light.
- one less cell to handle
- a bit more capacity and current handling
- it seems that 21700s are receiving more development than 18650, more power and cycle life, e.g. Samsung 50S, 40T3, Molicel P45B.
So is there any performance benefit to the 4x18650 configuration at all?
Some newer generation 21700/26650 single battery lights are catching up, or overtaking previous generation 3/4x18650 lights in terms of performance. So I’ll vote for single battery 21700 lights 