Absolute Noob question regarding E-Series SF and rechargeable batteries.

Hello, This is first thread here besides my intro a while back.
I Recently, picked a NIB SF E1e, (hex head) from a friend. I replaced the lamp with
a drop in purchased on CPFMP & found a couple minor issues in getting batteries
to work properly.

My question, is there a type of rechargeable 3.7v battery that fits a
stock E1? (The drop in is designed for at least 2.9V & cuts out with a CR 123)

Any advice would be great. I know of a boring service but rather not wait months
to enjoy/use my flashlight.

You simply need to look for an RCR-123 cell at 3.7 volts, find these and a charger and it should drop in.

Thank you! I have a 3.7 charger for 18350 cells which are too large. Sounds like a very simple fix.
Again-thanks!