yes, all that you have said is 100% correct, it would be better. . . BUT
these mondo leds will take an overvoltage without any problems when heat synced, and i am using the 3W ones that not only want more voltage, but will run at a lower voltage too. when the pack goes down, the light NEVER really dies, the current drops and it should run for a long time on this pack i made.
The LEDS WILL indeed easily be placed in series, to use higher voltages, with the exact same effect. like a 14.4v series set of them.
i do run them banked in all the 12v type lights i have in them now.
but them darn LI-ION cells as you have pointed out will CROAK die fail miserably (thanks to the blasted goverment regs) when they go over the voltage , they wont burn or explode, because on a SINGLE venting they die, and i cannot get the venting disconnect to re-connect :-( although it would be fun to make them burn and explode :-)
so if they step to far over the 4.25 the whole pack will be dead, i have been testing a bunch of them that were thrown out from laptops and stuff.
MOST of a "Pack" of lithiums that was deemed bad was still good, just a few series cells vented. total waste.
in other words, most tossed lithiums are GOOD, and it was the pack problems that killed them.
so if i put them in series, instead of this mondo block i have to have charge circuits for every one of them, and that means some sort of reduced efficiency, as high as -20%.
with this ONE cell , i have none of the problems, no circuit stuff that i couldnt build anyways :-) no offset cells or reverse charging.
in other words other then the voltage MAX, And excessive currents, and line voltage drop, and , there would be no problems.
i would certannly not try and run or light the whole house with any type of system like this, but it is perfect for my testing.
also this block could be charged at 50AMPS, and drawn off at 100A and it would still enjoy it , it can be brought down to 1V, and it will love it, it can be left down for months, and still come back when charged, and its self discharge is very low.
its almost like nothing can go wrong
SO
i will tell you as soon as as it DOES go wrong :-)
if they can make it i can break it, and durn well put it back together again :-)