1.4A Boost Driver Runtime with 16340 Battery?

So I purchased two of the nice, compact MS-V4 hosts from Sinner and have been planning to make one a 520nm laser and the other a 635nm laser. And while I think it could handle the heat from the Mitsu 500 (Sinner said it handled a 1.2A M140 diode easily), I have begun to worry about the runtime.

On the surface, (mAh/current)=Hours

The mAh rating on my AW 16340 batteries is 550mAh. So (550/1400)=0.39

.39 x 60 = 23.5 Minutes

But, during a fast discharge, I have read that you are looking at roughly half the capacity, so

23.5 x 0.5 = 11.78 Minutes.


Is my math correct? Would I be looking at an 11 minute laser? Maybe worse? Should I go back to the drawing board?


Thanks,
Isaac

It is correct if the driver draws 1.4A from your 16340 cell. The small cells can't maintain the high current draw for long. These are not 26650/32650 cells.

the math looks ok isaac. are you going to put a multimode red into that nice v4? i see you don't own a mm red by your sig. have you seen how horrible (imo) the beam looks with these diodes? such a nice sleek host cries for a single mode diode.
edit: just saw it was a boost drive, so it will draw more than 1.4A from the battery.

That is true, maybe I will get a 635nm single mode for it. I love the beam on the multimode diodes but I want a decent runtime. Also the conical shape of the focus adapter would look better with a single mode.

wannaburnstuff said:

That is true, maybe I will get a 635nm single mode for it. I love the beam on the multimode diodes but I want a decent runtime. Also the conical shape of the focus adapter would look better with a single mode.

Click to expand...

The single mode 635s are surprisingly bright, a really great beam, mine at 120mw is very bright, and you can see the dot on objects farther away than any other laser I have owned. Just an awesome tight beam and low divergence, I can easily see the dot on a stand of trees over a mile from my house around dusk. Any earlier than that its too bright out too notice.

I think my 120mw single mode 635 looks almost as bright as my 450mw Multimode 635 honestly, with a way nicer beam.

with a boost, you will be pulling more amps towards teh end of your discharge. Be mindful of the maximum safe discharge for your desired cell. :san:

I didn't think about it, but it isn't a boost driver. IIRC DTR uses a Linear driver with them and recommends one cell. But still....too short of a runtime.

My 1.5A Xboost M140 build runs perfectly fine for about 4-5 minutes with fully charged AW 18350 Battery.. Then the boost driver kinda struggles to get the full current draw and the output falls from 1.5W to just below a ~1watt and after a few second starts rising upto 1.35W thats when the little sink is a little too warm..

What 16340 you're going to use?

AW 16340 batteries 550mAh

It would work, like i said.. not stable for long !