You may never have an issue, but the fact remains, with four cells that connect all the positive contacts together, and all the negative contacts together, it is a safety issue. Even with the switch off, and internal short in any one cell becomes a 0 ohm load and starts drawing maximum power from the other 3 cells until the batteries vent, of burns through the shorted cell until it opens. In either case the condition can and has burned peoples house down. I will give you the fact that such a short is a somewhat rare occourance, and if it happened while using the light it would be apparent, and the light would be too hot to hold. Having had a major house fire due to teenagers breaking in and catching my house on fire, I will err on the side of caution. The protection circuits on batteries does not engage until 10-12 amps, so the batteries can supply between 40-48 amps to the light.
Well the 21700 Thrunite modified batteries are now showing on their website, and they are now 5000 mah. They are a very high price of 25.95 each. I will stick with the Orbtronics 5000mah protected 21700 that sale for 13.95. Using those requires removal of the plastic insulator head in the light. It also requires use of insulators that cover the unnecessary negative post on the positive side to use the thrunite batteries that came with the light also. So thrunite is selling their batteries of the same capacity for 12 dollars more, but includes a negative post that is not needed for any function in this light. The negative post on the positive side only contacts the insulator ring that also prevents the orbtronic cells from working. The insulator ring is held in the head by three screws that also hold in the PCB, so they must be re-installed after removing the insulator ring. A simple fix to save 48 bucks for 4 extra batteries. I have bought many batteries from orbtronics, and they use high quality cells.
Strange as it may seem, the actual feel of the added thickness of the base over the feel of a 4x18650 base is not a problem for me. I know the added diamater must be there, unless the carriage also adds that much in a 4x18650 carrier. I doubt that, but have not measured. I just know when in my hand, I am not thinking of the extra tube diamater. With the mods completed on the head and the batteries, I actually like the light much better. My next target is the Acebeam K75, if only I can someday find a sale or discount code to get that one in my light budget. That is just a very expensive light. Does it ever go on sale? I have been lusting over that one a while. If I can ever secure one in the 200-225 dollar range I will likely pull the trigger. Go figure, as an avid gun collector, 300 bucks is a low starting point for a decent sidearm. A few years back, I would never have even imagined spending 200 bucks for a flashlight though. I need cheaper hobbies.
I have been seriously looking into lights of this size for the first time since I started this hobby in the last month. I just bought a MF02s v2 sbt90.2, and I have been plotting my acquisition of the k75, which when all said and done seems to be the best in class after ouch research (which seems can be attributed to its reflector & driver 4 batteries in series I believe!?)
Anyway, I also am having a hard time with the $275 price tag.
But also - the WildTrails WT90 group buy which is only weeks away from fruition, which is also led by TexasAce! Tom E has been testing the Prototype, and looks like a clear winner in the same size as this Tn42, but with more throw.
I’m buying one, definitely. Oh and it comes in clear aluminum anodized. Check it out
The proprietary batteries from thrunit are the only option that I know of that will work without modifying the light. If others will work I have not found them.
I made an economic effort and bought both the TN42 V2 and the WT90 but I already had the K75, I can tell you that the latter is certainly superior to the other 2 but compared to the TN42 V2 the difference is minimal! I tell you that despite its 100 mm head, which is smaller than the K75 and the same size as the WT90, the Thrunite has performances in relation to the dimensions and weight of a higher category very close to the K75 instead the WT90 does not reach what the specifications promised and is inferior to TN42 V2. I believe it was really well designed and I also believe that much of the credit is due to the high quality standard 4x21700 battery pack although I also use the Molicel P42A which also give something more than the stock batteries.
I see your concern and it is possible.In the 10 years of using high powered stock and mostly modified lights, I have never had an LED or driver fry because of using max output 80% of the time and low 20% to cool the lights. Actually in late fall and winter they can stay on max until battery depletion.
I enjoy using my lights that way…if one does fry well I will accept it.
