as I have previously stated more than once, RCR Li-Ion cells simply do not survive the "institutionalization" problem. "Institutionalization" means adapting flashaholic lights to a non-flashaholic work-a-day world. What will easily survive the normal consumer/use are primarily AA cells, or maybe AAA or maybe C and D cells. or maybe the non-rechargeable Lithium cells for police/military and firefighters. Who are we talking about? Plumbers, building maintenance personnel, mechanics, teachers, etc.etc.etc. This is most definitely NOT flashaholic territory where afficiondos and enthusiasts will willingly spend lots of $$ and time for an edge in light output or small size or some other esoteric feature (HID vs LED vs Quad-LED).
I have tried to educate many different people in many different user environments and reduce the flashlight and battery complexity for them - all attempts have eventually failed and the people went back to something that did not require any gung-ho techno-geek to tell them what to do. They all like the smaller size and greater brightness from an RCR flashlight system....until they run in to the charging and multiple cell problems of RCR cells. They do not easily manage the problem of matching the RCR cell and charger. and then there is the problem of an "emergency" battery replacement when they are away from their specialized charger and they have to purchase a replacement Lithium cell or 2 in brick/mortar stores - ehhhhhh, that nonsense ceases very quickly! The final incentive killer is an protected RCR cell that cuts off the current when the cell voltage drops too low for safety. Try explaining that to a plumber who lost his light 20 feet into a narrow crawl space. Let that happen more than once and they will drop the idea of RCR Li-Ion cells instantly. Graceful degradation to any flashlight system is important. a more engineering word is "robustness".
Bottom line: I have progressively pulled back or exchanged all RCR Li-Ion cells and flashlights from over a dozen typical users, even those that do understand the nominal needs of RCR Li-Ion cells. Nearly all of the flashlights left in the hands of non-flashaholics are stuffed with non-rechargeable Lithium cells. and as those fail, and they do fail, I am replacing them with AA or possibly AAA flashlights with Ni-MH LSD cells.
Also, FWIW, I really have to admit that the LSD NiMH cells solved a major problem - self discharge. Now users are asking for more LSD cells for their digital cameras - they can rely on adequate charge left after sitting on the shelf for a couple months and still have a standardized rechargeable battery. Even Nikon brought out the L20 with standard AA cells although their high-end digital cameras require too much power density for the small size and they switched to non-standard Li-Ion battery packs.
as for protected RCR cells, here is a good example of a problem: an EagleTac flashlight lost it's reverse-polarity bumpers - as usual. The problem was that a loose bumper bridged to cause a short in the head of the light. The protective circuit in the AW RCR123 cell sacrificed itself to protect the user. However explaining the idea of "protected" Li-Ion RCR123 cells and why the protection is needed was not easy. another case of back to AA cells. 'nuff said.
signed - an old engineer who has lost too many technology battles....
