14500's or 32650's or NiMH's or ??? 2D (P7) and 3D (HotWire) Mag Mods

[fneuf]

While having almost finishing sourcing parts, for 2 mods:

• A 3D which will host bulbs thanks to JM-PhD-D1 / Kiu socket solution
• A 2D which will host a P7 / D2flex+HipCC solution

I'm questionning myself about the energy source. For both of those setup, would 14500 be a good idea over NiMh (eneloops) ?

Considering a 14500 would rate 3,7V on load (what is your experience on that point, is this 3,7V realistic?):

• In a 9AA->3D standard holder (batteries in serie) that would go for 33,3V (so under the 40V limit of the JM-PhD-D1)
• In a 6AA->2D standard holder (batteries in serie) that would go for 22,2V (so under the 24V limit of the D2Flex + HipCC combo)

How does the 14500 handle current load?

• The 2.8A of the P7
• Up to the 7A of 66430 bulbs (I mostly plan to use 5761 (~5A), but 1185, 1164 (both 3/4A), and 64430 bulbs will be also tested)

Would it be more intelligent and useful to mod the fivemega holders to have respectively:

• 3s3p for the 3D
• 2s3p in the 2D

What do you think?

 

[fneuf]

Re: 14500's or NiMH's? 2D (P7) and 3D (HotWire) Mag Mods

Ok, I saw I did this wrong.

Here are new data based on theory+thought:
(I'm considering 85% of efficiency of the drivers)

1 - P7 mod on a 2D Host

• P7 : 3,5 x 2,8 ~= 9,8W
• D2flex + HipCC : 9,8 / 0.85 ~= 11,5W
• Source : 6 14500 in serie : 6 x 3,7 = 22,2V

Result : current draw on batteries => 11,5 / 22,2 = 518mA
Behaviour at protection treshold : 11,5 / (6 X 2,75) = 696mA

The 14500 batteries seem to be a great idea for this mod.


2 - Hotwire mod on a 3D basis

• 1164 : (10,6 x 4,5)/0,85 ~= 56,1W
• 1185 : (12 x 3,5)/0,85 ~= 49,4W
• 5761 : (7,6 x 5,7)/0,85 ~= 50,1W
• 64430 : (11 x 8)/0,85 ~= 103,5W
• Source : 9 14500 in serie : 9 x 3,7 = 33,3V

Respective results: 1,7A /\ 1,48A /\ 1,5A /\ 3,1A
Respective behaviour at protection treshold : xxxx / (9 X 2,75) = 2,2A /\ 2A /\ 2A /\ 4,2A

It seems more "extreme" to use 14500 in this mount.

What would be your advices ? Are there somewhere hidden some other chemistry battery in an AA size that could be used ? Other form factor pretenders for this app ?

 

[Hack On Wheels]

Re: 14500's or NiMH's? 2D (P7) and 3D (HotWire) Mag Mods

I would personally use eneloops (nimh) for the 2D for a closer match of Vin to Vout. I would expect that to be more stable and efficient. The high voltage of six li-ions would be pointless.

For the 3D I would use 3 or four large cells (D or C) which should have high capacity and good stability at a high current draw which I would expect with a high voltage incan. Less cells and possibly no adapter ( or just a simple sleeve adapter) would keep things much simpler.

 

[fivemega]

Re: 14500's or NiMH's? 2D (P7) and 3D (HotWire) Mag Mods

What is advantage of using 14500 over Eneloops for hotwire M*g?
3 parallel 14500 will have nominally 3.7V, 2250mAh, $27
3 serial Eneloops will have nominally 3.6V, 2000mAh, $12
Long time ago I made 3S/3P 14500 battery holder because LSD NiMH batteries were not popular.
There are many other applications such as 14.8V in 1D M*g which using 14500 cells are the only solution.

 

[fneuf]

Re: 14500's or NiMH's? 2D (P7) and 3D (HotWire) Mag Mods

I would personally use eneloops (nimh) for the 2D for a closer match of Vin to Vout. I would expect that to be more stable and efficient. The high voltage of six li-ions would be pointless.

For the 3D I would use 3 or four large cells (D or C) which should have high capacity and good stability at a high current draw which I would expect with a high voltage incan. Less cells and possibly no adapter ( or just a simple sleeve adapter) would keep things much simpler.

Thanks for your comments. So you think having between 7,8 to 5,4V is a better idea over 22,2 to 16,5V. When you speak about stability, what do you mean? The time the setup will run in regulation? Would using 2x18650 be another solution to consider?

Here the current draws on eneloop solution :

1 - P7 mod on a 2D Host

• P7 : 3,5 x 2,8 ~= 9,8W
• D2flex + HipCC : 9,8 / 0.85 ~= 11,5W
• Source : 6 eneloops in serie : 6 x 1,3 = 7,8V

Result : current draw on batteries => 11,5 / 7,8 = 1,5A
Behaviour at low-volt treshold : 11,5 / (6 X 0,9) = 2,1A

2 - Hotwire mod on a 3D basis

For the C, D cells are you speaking about NiMH or Li-Ion cells?
Would D NiMH sustain something like 12A to feed a 5761 (50/ (3 x 1,3V))?
Would D Li-Ion sustain something like 4,5A to feed a 5761 (50/ (3 x 3,7V))?

 

[fneuf]

Re: 14500's or NiMH's? 2D (P7) and 3D (HotWire) Mag Mods

What is advantage of using 14500 over Eneloops for hotwire M*g?
3 parallel 14500 will have nominally 3.7V, 2250mAh, $27
3 serial Eneloops will have nominally 3.6V, 2000mAh, $12
Long time ago I made 3S/3P 14500 battery holder because LSD NiMH batteries were not popular.
There are many other applications such as 14.8V in 1D M*g which using 14500 cells are the only solution.

My aim is to keep Mag mod in "usable form factors", for me it means 2D or 3D. Therefore I'm trying to put all powering solution in the equation to find the perfect one for my aims.

I already have a 9AA batter holder, and am using AAs in it. I'm just trying to see if there are not other options, as I would like to be able to light a 64430 in a relatively small package as a demo light. But still able to run 5761 as a more versatile hotwire. And all in the same light (the 3D host).
On the other side I would like to have a usable, multi-mode LED maglite, in a convenient package with an acceptable runtime (the 2D mod).

Would 3 x 32650 be a better solution. Would they fit in a 3D stock body? That would gave me around 3,7V and a max draw of 4,5A for 5761/1164/1185 (and... 9,3A for 64430).
Like http://kaidomain.com/ProductDetails.aspx?ProductId=2751 or http://www.bestofferbuy.com/protected-single-d-liion-3265032600-p-14495.html.

 

[fneuf]

If I stick with AA, is it realisable to power up a 64430 with 9AA in serie or should I forgot that option and stay on the 1185/5761 class ?
To go further, 18650 are clearly to big for unbored Mags, but 17650 or 17500 or even 16340 form factors are another option. In addition, new chemistries such as LiFePO4 or LiMn capacity to overcome high rate charge and discharge should make them pretty aimed for hotwire ?

 

[lctorana]

You're probably over-analysing this, and thinking about it too much.

First just make a Mag85 with 9AA, in your 3D, use it for a while, and then think about the next step.

By using a 9AA battery holder and a bi-pin adaptor, the mod is totally reversible.

 

[fneuf]

That step is already achieved :twothumbs

Am currently waiting to receive a couple of 1164 an 5761.

And for now, the next step would be to buy Kiu socket and Jh-PhD-D1 regulator. :candle: