Oh, you mean unrelated to what fits in this light?
Most name brand are around $10 to $14. A good deal on a 4000mah would be the Sofirn. It’s about the same as the Samsung 40T. High amperage and true 4000mah. They are $6.28 each or 2 for $10.22. The price gets cheaper as you order more.
Another good bargain 21700 is the LISHEN LR2170SA which is the same as the yellow Liitokala lii-40A. Both 4000mah. I think these are also around $6 to $7 each.
If you want a high capacity cell, like a 50E, you’ll have to spend $10 on it.
I am wondering how would this light compare to the Lumintop ODL20C, almost the same specs except for battery and a better UI, I am interested in a beamshot comparison, that would make me decide if to buy it or just keep my ODL20C.
If you see a review or comparison online let me know.