Tailcap measurement

Ok I know someone can answer this for me, a flashlight in parallel (2 18650’s) to get the tailcap measurement, you test one side then double it? or test one side then the other and average? ORRRRRRRRR……???

i would bridge both cells because a single cell has a higher voltage drop as 2 which leads to different results

always try to measure as close as working contitions…

for example (rough numbers from mind ):
i played with (not so good) laptop pulls…
1 cell delivered 4 A
2 was good for 7A
3 or more topped the driver at 8A

It considerably depends on the emitter that your flashlight uses. Maybe you could give us more information on what flashlight/batteries/emitter do you use?

it is a side by side configuration, T-6 emitter and side switch

Are you absolutely sure the cells are in parallel electrically and not only side-by-side but infact they are in series?

no I am not absolutely sure, it is this light though…….


Alright that is indeed in parallel electrically. You will need a thick copper wire to unite/bridge both cell ends to a proper reading, but if the cells are weak reading will be low.

ok will try that, thanks

Can you unscrew/disassemble the tailcap? There must be some kind of a wire bridge connecting the batteries.