Anyone know a good source of Ni MH D cells. This looks good to me: http://www.batteryjunction.com/1dni10reba.html .
I can tell you a not-so-good source of D and AAA cells — cheap Tenergy NiMH, light blue with a dark blue band at the negative end.
Lots of those were for sale cheap for quite a while last year and longer ago, around the time Tenergy took them off their website.
You can still find them for sale here and there. I bought several batches — they’d either aged out on the shelf or been stored too hot somewhere in the sun, low capacity and didn’t hold charge very long.
Cheap though … they’re Ok if charged right before they’re used, for a day or two.
Dang. Got mine today, N&K Trading, North Brunswick NJ.
Lights up, but the zoom does nothing but make a brief little gritty noise when the silver button is held, then silence. No sign of any change in the actual light pattern, no movement inside the head.
EDIT: slight twitch inside the head, in and out, maybe a millimeter, not enough to affect the beam spread at all.
Motor pulls enough that the emitter dims slightly while the motor’s trying to zoom/focus and failing.
The amount of the twitch varies a bit, definitely feels like something’s jamming the zoom mechanism in there.
And it doesn’t open up, dammit.
The zoom button doesn’t depress noticeably at all. Should it?
EDIT -no, that’s how it’s meant to work
The silver button feels like it’s just an electrical sensor/contact.
The power button is usual black rubber cover over a clicky switch.
High, low, strobe as expected.
… contacted Tmart “chat” ….
They will email me after they “contact the relevant department”
Well, perhaps this is why the gray ones are on sale (but the other colors aren’t).
There’s a little twitch inside, feels like it’s got something jamming the zoom.
Sorry that happened. It seems I was lucky. Yes, the silver colored button does not move. It must be an electrical sensor of some sort. Maybe it senses capacitance at a high frequency.
I see now, in addition to black and grey with no brand at $23.13, there are ones branded TangsPower for $42.64 in black and bronze. The descriptions are all wrong, but in different ways. I don’t have experience with Tmart, and I don’t have much idea what postage back to New Jersey would be. You should send them a video of trying to make it work.
I finally ordered three Tenergy high discharge NiMH D cells from Battery Junction for $30.54 with postage. These are old “tech” cells that no longer appear on the Tenergy Web site. Nothing is said about self-discharge.
My alkalines are already down below 1.5 V from me and two three year olds playing with it. At 1.44 V from each of my alkaline cells, it is down to 0.6 A on my cheap meter.
I ordered 2 and received them today. I received one black one, and one grey one. But had ordered 2 grey. No biggie. Amazingly both work despite having slid out of their boxes in the shipping bag.
Not particularly bright, loud, and a fair amount of drift in the zooming mechanism if trying to stop between flood and zoom.
Despite all of that they’re fine for the price paid, and if I can get one of them apart safely it’ll make an interesting host.
I heard from Stupid (not her real name) today — the chat support bumped me to them two days ago.
I sent them a video with audio so they can see and hear the problem and asked for a RMA and shipping label, or a replacement.
Here is a listing that actually says something bout the mechanism (3*AA/3*14500): 
And a 18650 version:
And another 18650, but the mechanism is not clear:
Tmart tried to repay with points instead of money — to be credited only many days after return of the problem light
and
in the fine print
“A2: 10% of the order amount can be paid by Tmart Points. When you check out, the system will show you available points in this order.”
No way.
Waiting for a return label and a refund.
I would love to see how the zoom moves
You can hear at the end that it retracts when turned off.
now that’s interesting (though I expected it to be noisy gear grinding zoom)
thanks for the video 
My Tenergy cells came. They are charged to 1.29 V, though nothing in the description said anything about low self discharge. Perhaps they charge them before shipping them out.
I get 1.0 A with the rechargeables and 1.25 A with the Alkalines. Very disappointing! I had expected a big increase. Either the current is not as sensitive to the battery resistance as I expected, or else the NiMH cells have high internal resistance.
I’d suggest faking up a holder for three good Eneloop AAs and see how they do, albeit briefly.
And try putting the Tenergy cells through break-in cycling if you have a charger that does that.
The blue Tenergys are pretty old. But after cycling a few times in a Maha break-in mode, mine are anywhere from 1.31 to 1.39 a day after being charged.
I did have several DOA (0.0something voltage, and “High” in the charger) when I bought batches of them, and that was a year or more ago.
My charger will cycle them, but it has only two slots, only one amp. and it will take magnets to use both slots, so cycling three 10 Ah cells will take some time. It discharges at half an amp. which is almost a day!
I still don’t see any of the more recent grey ones for sale anywhere. The other choices are the white and blue ones, or rigging 3 x AA substitutes.
This is the size of NiMH cell my car uses. I don’t suppose it would miss three, lol.
aside, don’t bother trying to reply once Tmart’s chat bumps your problem to one of their departments.
Their email is write-only:
well, I got a rather mangled return label in email (misaligned text overlapping the border, and coarse pixels — low resolution PDF). Will try sending the thing back tomorrow.
aside, don’t bother trying to reply once Tmart’s chat bumps your problem to one of their departments.
Their email is write-only:
well, I got a rather mangled return label in email (misaligned text overlapping the border, and coarse pixels — low resolution PDF). Will try sending the thing back tomorrow.
I ’oogled: tenergy nimh D
and then image search — finds an awful lot of the outdated blue cells, a couple of images of the gray (which I’d never come across before)
but the few I checked were labeled “Out of Stock”
Seems only the white ones (regular and LSD variety) are current.
Didn’t poke through the rest to see if they’re valid sellers, might be worth looking.
Doesn’t hurt a thing. Light works fine. And these are with Eneloops.
Four AA cells will just fit in the tube. A dozen white Eneloops from Battery Junction is $32.95 plus shipping, just a little more than the three D cells cost. It would then need conducting spacers at front and back to make up the length and contact the spring and center connector.
Or 4 AAAs is shorter than 3Ds by 4.7 mm. 4 S x 8 P AAAs would fit at around $2 per cell + $20 for four 8 cell chargers. The extra voltage would make it brighter and stay bright longer.
Or if one can get it open and do a heavy mod. it could take a buck driver and 2 x 26650, with some padding, or whatever other sizes one had from battery pack pulls.
I am now charging the Tenergy D cells, then I will cycle them. The positive contacts on my charger are not iron, so I am using cork to hold thin contacts against them.
After penetrating oil, the head still doesn’t screw apart with my hands.
With the cells charged to about 1.4 V by my LiitoKala, I get 1.4 A, similar to with nearly fresh alkalines.
I am starting to cycle them.
I came across 4xAA adapters recently — searching, I see Garrybunk started a thread here: 4xAA Battery Carrier now at CNQG (Near Fit into Maglites)
The ones I got almost but don’t quite fit this 3xD zoomie, but probably could be carved down (the end disks are a bit too large diameter)
Oh, and in packing the 3xD to send back to Tmart, I notice a hole punched through both the mailer bag and the crushed white box at one end.
I suspect the head of the light got stepped on badly; looking closely, the red ring on the lens end is a bit squeezed on one side.
Tmart has really terrible packaging — a thin plastic mail envelope with no bubblewrap or anything, just plastic film.
The light comes in a thin white cardboard box — and they’d half-wrapped that — leaving an inch or so of the cardboard box at each end unprotected — with a slab of bubblewrap taped around the middle.
I’m going to pad it rather better for the return mail and keep photographs.
I cycled two of the three cells. My charger measured capacity on discharge. I got 8.4 Ah for one and 6.8 Ah for the other. These are supposed to be 10 Ah cells, so they do appear to have suffered from long storage. I will cycle the 6.8 one again while I cycle the third cell.
The second time I cycled the poorer cell it held only 5.5 Ah. The third one held 9.0 Ah. Maybe I will contact Battery Junction about the poorest one.