I decided to test a 32650 li-ion cell today, so here are the data results I have gathered so far.
This cell is of the large-category (“long-D”) li-ion cell type, manufactured by Feilong, 32650, (gray) 6000mAH-rated battery. 3 separate cells have performed surprisingly well so far, each within +/-3.0% of another. Average capacity in this testing environment was between 5500-5700mAH using a constant-wattage draw method for drain. This method simulates actual buck or boost driver conditions, as the initial wattage at start-up setting is the wattage held through the drain cycle. In other words, as the battery voltage sags, the amperage draw is increased to maintain the same total power output. The cells were charged to 4.185V. That is the voltage where the tests begin drain from, and at 2.980V the test ends on the battery, which is a conservative voltage minimum for high-quality cells.
Not many lights use multiple 32650s, some use singles, but if you have the option to, these cells will perform. I use them in one of my personal favorite lights, the TR-J20 in 3S configuration.
I use a “battery-workstation” to perform cell testing. It is a FMA-Cellpro Powerlab 8 V2 model workstation. An FUIM3 USB interface is used for PC connection. It is a strictly DC powered supply, so to power it indoors, a 1200W AC->DC 60A converter is used.
More graph data will likely follow in coming days, or additional cell tests (if you have a test request, PM me). Next will likely be a 26650 MNKE test.
The testing setup;
Master 15-24V 60A supply:
PL8 Workstation ouputting data over FUIM3:
Test #1; 7.50A Starting Draw, 4.185V Cell Start, 31.4W constant (Total drain time = 38:20);
Cell Voltage Drop:
AH Total (5533mAH):
(TEST #2, will update soon)