Hi Rishi, and welcome to CPF!
I don't own a BC-10, but do run "3 Volt" rechargeable cells, both LiCo/ICR with diodes incorporated to lower the voltage closer to 3 Volts (which is what the Tenergy 900mAh "3 Volt" cells are), as well as LiFe/IFR (LiFePO
4) "3 Volt" cells.
Neither of these type cells are actually 3 volts, but run in the 3.2-3.4 Volt range when under load. I only use these cells in single 123/16340 lights, and while they often run a bit brighter, as well as warmer than when using a CR123A primary cell, they seem to be OK.
No guarantee in your BC-10 though, as JetBeam specifies only CR123A cells for this light, unlike my RRT-0 XML which will run on CR123A, RCR123/16340, or AA/14500 cells. Oddly enough, it does not run well on either type of "3 Volt" cell. It flickers annoyingly with these type cells, I assume because the driver can't determine whether the cell is a 3 Volt CR123A primary, or a "normal" 4.2 Volt Li-Ion, and as a result, the drive voltage is unstable.
And just as info, JetBeams are "Chinese lights", as well as Nightcore (a sister company, under Sysmax in Guangdong, China), along with, Olight, Fenix, TrustFire, UltraFire, XTAR, 4Seven's (a U.S company, but lights are made in China), Thrunite, Sunwayman (who'd have ever guessed!), Lumapower, as well as just about every other light mentioned on the Forums. It wasn't always this way, as CPF was started by SureFire (a U.S. company) fans/collectors, custom light builders, and modders from around the world. But, anyway, things change.
Dave