HaikeLite MT07 Buffalo mod to 8 batteries

Hi all, sorry if is a dumb question. Is it possible to add 4 more Samsung 30Q 18650 3000mAh 15A Batteries to my MT07 without making any changes to the driver or other electrical devices? I was going to maintain the 6v configuration by placing them in parallel. I’m considering making a longer battery tube to accommodate the extra batteries. It will require some re-wiring in that area, but I’m not sure about the extra mah and or volume accessible to the circuitry. Any thoughts are greatly appreciated :slight_smile: . I don’t want to damage it or me ! LOL ……

The flashlight is a little short to handle for me. And that would be 8 batteries total 2 in series x 4 = 6v.

I’m not a modder, but I have thought about this as well. From my understanding, all the current of this light (MT07) runs through the batteries, so there is no current running through the battery tube. The latter is the case for example with the Convoy L6 or Noctigon M43.
If you build an 8x18650 tube, then yes all the four rows of two cells in series must be parallel to maintain the original max 8.4V voltage. So this means current must run through the battery tube, and near the head the battery tube must be connected to the shiny ring which is the original negative.
Also, all four negatives at the tailcap must be wired to the battery tube. So the original rotating tailcap must be altered somehow.
I think this is ok, but you might want to check this info.

I forgot to mention something important. Haikelite should be releasing an 8x18650 tube soon as well. It’s delayed a bit because of problems with their new light. There should be two variants, one with max 8.4V and another with max 16.8V.
You might want to check this out first.

These are initially designed for the MT09R and MT07S which have a slightly different contact plate, but maybe it’s just a matter of a different board attached to the tube; the tube should fit the MT07. Of course you need to check this out as well.

Thanks, just checked it out. If they can supply the tube, I will just order one and make necessary changes to it.

Guessing there are no other issues with the stock flashlight accepting an additional 4 batteries wired to match stock 6v ?
That extension was for the MT09.

The driver is not going to notice anything differently. Well as long as the wiring is ok of course; this seems to be the only thing that requires modding.

I have a sample of one that I should have between the 17th and the 19th. Once it arrives I can hopefully answers some of the questions that we all have...

hIKARInoob

Thank you for that info, I checked it out and the MT07 I have is a 4S 16v. I will get the extended tube when it becomes available.

That’s interesting. The 4S variant of the MT07 and MT03 were only offered during the group buy over a year and a half ago along with the 2S2P (8.4V) variant. Most of the driver problems were found in the 4S variant, therefore Haikelite ditched this variant (I assume this is the reason) and continued with the 2S2P variant only.

Edit:

The MT07S reintroduced the 4S configuration again not too long ago. I just checked the Haikelite site, and it says that the MT07 is also 4S. Interesting shift.

Thank You :slight_smile: hIKARInoob
Crap, I did not know this or I would not have purchased it. I did not know about the 2S2P / 4S variants or driver problems until after buying it. I will search this here at BLF and email HaikeLite to get some clarification about driver problem fixes they have made. If i do not get a satisfying reply, I will request to return the MT07 for refund.

BTW, is there a season for wanting the 4S version in the group buy ?

The returning to 4S for the MT07 should be a fairly recent move by Haikelite. About half a year ago they released the MT07S with the 4S battery configuration, and apparently Haikelite is satisfied with the performance so they went back to 4S for the MT07 as well. So the current 4S design for the MT07 is most likely not the same as that of the first generation MT07, so you don’t have to worry about that.

4S means max voltage is 16.8V. If batteries are depleted to 3.0V each, then total voltage is 12.0V
2S2P means max voltage is 8.4V. If batteries are depleted to 3.0V each, then total voltage is 6.0V

The voltage for the emitter required to produce about 5000 lumens is roughly a bit under 7V. You also loose a little bit of voltage for the driver.
This means that with a 2S2P configuration you’re only getting max output with freshly charged cells. At a certain point when batteries are depleting the max output cannot be achieved anymore because you don’t have sufficient voltage.
This is not a problem with a 4S configuration where you always have sufficient voltage. You can check out the runtime graph here (scroll down) where the output remains constant over time (as long as there is sufficient cooling): https://www.banggood.com/HaikeLite-MT07S-XHP70-4500LM-Super-Bright-Long-Range-LED-Flashlight-500M-p-1186558.html?rmmds=search&cur_warehouse=CN

Thank You :slight_smile: .
And that is good news. I looked the run times and Thanks for explaining the voltage and why the 4S was desired, I understand now. The 4S configuration will never drop below 12v and the 7v ’ish required by the emitter to produce 5KL will always be supplied. There is so much to learn about LED’s, batteries, flashlights, etc… We are enjoying this very much :beer: Also, when I get a reply from GearBest, we will post it here for you.

That is Great news, I’m a Happy Camper now :slight_smile:

Now I can move fwd with design and building of the 8 x IMREN 21700 4800mAh 30A battery tube for it. :slight_smile: .

If you decide to build a 4 x 21700, I would be interested in buying one. The eight cells would be too long for my use but I sure can use the increased runtime.

If Haikelite would build either the 8 or 4 cell 21700 tube option for the MT09R and MT07, they would have a huge hit. Maybe you should contract with them like TA did for the drivers of the MT09R :wink:

Wish you the best of luck and look forward to your results.

JHBUDGETLIGHT

I’m just starting the design now on the free version 2D cad. Siemens Digital Industries Software Online Store

I will make it from some scrap aluminum at work during lunch time. The battery tubes HaikeLite uses are extruded so if you think they may want to make some, it will likely require them to have dies made for this bigger battery and still fit the stock flashlight head. I will check to determine if it is dimensionally possible in a production environment, for cost purposes.

I will let you know later today here. :slight_smile:

I had some drawings done and have a fair idea how to make the tube but I’m having trouble posting the images smaller from Imgur.
Out of time now, will try later. I’m also not sure about the stock threads, they have to be a modified TR 48 x 3 mm. It checks 48.8 mm on the diameter and is neither metric or standard thread. Or at least I have not found it yet…

Here is the end view of the stock tube with dimensions. Still have not located the exact thread type yet.

Here is a draft of the minimum size for the 21700 battery. I do not see it going into production
because of manufacturing cost to make it fit existing threads. I’m looking into other possibilities
than taking a solid chunk of aluminum and machining it. Let you know how this goes.

I have contacted GearBest and Haikelite and unable to obtain any stock battery tubes to modify ( lengthen )
by cutting in half and adding the extension in the center of the stock tube for a 18650 extension.
We will continue this adventure……