If the FET Richard uses is too high in resistance I have several options I can go to.
Some firmware does not use the 7135 chip. I’ve built a LOT of drivers and can’t recall 7135 chips giving me any issues. No matter, I have those as well.
What I didn’t have was a 30mm pcb to build my own. Lots of others, both bigger and smaller. Of course.
I don’t have that Lishen cell, but the new P45A is en-route as we speak. The 40T just made a serious showing to set the bar… 30.3A in a Sofirn SP70 with the SFH55 emitter producing 8590 lumens at start-up.
I’ll have to try and find that Lishen.
FAIW, I changed a lot on the driver I bought. New ATTINY85, Anduril, stacked 7135 chips from a 380mA bin, and an Vishay-Dale SIRA00DP T1-GE3 MOSFET. Also 115 strand 18 ga silicone wires and a nickel plated Hornady 9mm casing for the positive contact. 
Get some SIR178 next time you make an order, SIRA00 and other FETs used in these DD driver are often 4.5Vgs rated (logic level) and the ON resistance increases quite a bit below that at 1S li-ion voltages, SIR178 (2.5Vgs rated) has very low RdsON even at 2.8Vgs, on top of not costing much.
The A00 is rated at decimal point levels in the area I use a flashlight. (3.5-4.2V)
I am out of 404 or I’d have used that.
Still, the A00 is cranking out some serious lumens, especially considering the heavily diamond faceted reflector I’m using.
Thanks for the heads-up on the 178, will check into it. Not modding lights much anymore as there are new interests gobbling up my time. Although lately my buddy has been asking a lot… lol. Bored old men. Whatareyagonnado?
Edit: Wow! That does look good! I see that it came out while I was AWOL. 
Might have to try a new Ledil and tack a handful of these on! Thanks!
Lishen 21700 cells ordered from Neal. SIR178DP FET’s and a 70mm Ledil reflector coming from DigiKey.
I just ordered some Lishen 21700HP cells from taobao, same seller that sells the NS59v2 (for half of Neal’s price). Fingers crossed they show up, even if it takes many months. If it goes well, I will share results from lux testing (don’t have a lumen tube).
Great and best of luck; I can’t stand waiting on vendors once I’ve paid. When the P45B grade A from Liionwholesale comes out I will order and measure with my TA lumen tube, just for the sake of completing my list below.
I think have one of the most consistent battery testers around, the Nightwatch Chaos 
What is the IR and date code for the P42a you tested? It’s unusually low.
Also I ordered a Nightwatch Chaos as well, but from taobao.
Don’t know IR. How could I tell date code? It’s in the picture below. I got it from Neal for my Haikelite HK05 just a couple months ago.
Long story short: The Haikelite Neal sold me has a defect. The red button light is always on unless I tighten the body to the head just so, not too tight not too loose. It continues to be on/off and drove me crazy but Neal wouldn’t send replacement. Right now I am at the perfect spot and don’t want to undo to test battery.
I wasn’t impressed with it. Test all 3 batteries with TA lumen tube in various lights. It’s about same as 40T, and not as current-discharge strong as 30T or Neal’s LR2700HP
It doesn’t look like genuine Molicel, I had it happen before that some “P42A” batteries I bought from chinese sellers ended up at less than the minimum specifications from Molicel, likely were rewrapped 4000mAh 35A lishens.
The font size doesn’t match up with the Molicel P42As I bought from li-ionwholesale and illumn, and the wrapper is supposed to be slightly shiny. I recommend getting a different one to be sure it’s legitimate.
The date code for Molicel is LYMDD SS (discard the 1st digit “2” - not sure what it means)
A=2010, B=2011, C=2012, D=2013, E=2014, F=2015, G=2016 etc. If it was genuine, the cell is from 2022-03-03.
Thanks. In real life it looks pretty close to this one from li-ionwholesale. Neal’s after-sale service not exemplary but I don’t think, and hope, he’s not selling counterfeit. If true would be disappointing.
It is possible he doesn’t know it is counterfeit, I bought some suspiciously cheap “P42A” batteries from the aliexpress store of a popular brand on here (do not want to name them) some time back and they were way worse than the datasheet minimum, likely being Lishen LR2170LA batteries where the typical capacity is 4000mah (the batteries were between 3894mAh and 4051mAh).
I would recommend using a battery analyzing charger to test the capacity and internal resistance and report back, most XTAR chargers can do both and are pretty cheap.
In my Sofirn SP70 equipped with the very hungry SFH55 emitter the new Molicel P45B makes 7390 lumens as compared to a 40T producing 8590.
Awaiting Lishen 21700’s from Neal.
Interesting; that seems way too low if it doesn’t even match 40T. In my lights P42A matches 40T when it comes to output, and P45B is much more current capable than P42A.
BTW that SFH55 LED is a great battery current “tester.” I have Mateminco PD90S with SFH55 and outputs always sag big time 1 minute after Turbo start, regardless of what battery I use. Not sure whether it’s thermal stepdown or not, but I believe it’s the battery saying if you draw any more current I’m going to die.
I thought I did something wrong until I see the 1lumen review. Exact same sag, to same output, at same time. From Mateminco PD90S review | 9,300 lumens and SFH55 | 1Lumen.com
It could be thermals, does it still happen if you’re cooling the head with something? Otherwise it could be a programmed stepdown.
I have Anduril running it, set thermal step down very high.
I have never seen an instance where any cell can match the 40T. Especially Molicel.
You could try running the tests again using the “momentary turbo” as it bypasses thermals.
It’d be a good idea to include where the batteries were from, as the performance is very inconsistent between each person’s testing (not doubting you, but the battery sources), with Mooch (afaik uses only grade-A for Molicel) tests were showing the P45B equal to the 30T, and better than the 40T, while the 40T slightly beats the P42a in initial voltage sag. Perhaps some counterfeit P42As got in the supply chain, or there was a bad batch at some point that didn’t get caught by QC.
I typically buy cells from 18650Battery in Georgia or LiIonWholesale in Houston.
liIon Wholesale states…
“ AUTHORIZED MOLICEL/NPE US DISTRIBUTOR - GUARANTEED TO BE GRADE A, UNUSED, AND MANUFACTURER APPROVED.”
P45B from Liion-wholesale is here. Looking forward to the shoot out vs Neal’s Lishen.
