Are you looking for ones that have USB port built-in? These are usually repackaged cells, so it's hard to tell what is truly inside, another words, it's a c_r_a_p shoot. They also typically have less capacity because the charging circuit and port take up some of the available space. Also, most of these don't handle high current well, which would be the main reason for one to use li-ion cells in flashlights. Otherwise, if you're not going to utilize high current, then just stick to NiMH cells as most of these flashlights support both Li-Ion and NiMH.
With that said, these ones tested reasonably well:
Keeppower 14500 950mAh P1495U (Blue-white) 2020 Official specifications: Voltage: 3.60V Rated capacity: 950mAh Minimum Capacity: 900mAh Discharge cut-off voltage: 2.50V Charge voltage: USB 5V +/- 0.5V Standard charge current: 330mA Maximum constant discharge current: 2A...
budgetlightforum.com
Vapcell INR14500 950mAh P1409A (Black-red) 2020 Official specifications: Nominal voltage: 3.6V End-of-charge voltage: 4.20V End-of-discharge voltage: 2.50V Typical capacity: 950mAh Minimum capacity: 880mAh Standard charge: 500mA, CCCV, 50mA cut-off Quick charge: 1000mA...
budgetlightforum.com
They are slightly longer than usual, so make sure you have room in your light to accommodate them.
If you want reliability from a reputable manufacturer, Sanyo makes good 14500 cells, but they don't have a built-in USB port, so you need an external charger.
