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FrozenGate by Avery

Will my batteries handle my current?

IsaacT

IsaacT

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I have the parts for my first handheld build on the way. Due to not being able to find a good boost driver that fit my needs I am using a buck driver set to 2.1A powering a 9mm 445nm Diode.

Since my Host is 18650 sized, I will need to use two 18340 cells but I saw the current rating on my cells and they are 880mAh each. Will these be able to handle my current draw??? Have I wasted money on a driver that I will now need to discard?

Any assistance is appreciated,
Isaac
 





2.1A * 4.8V = 10W

Assume 90% driver efficiency means 11W draw from the batteries. 11W/8V = 1.4A
That's pretty much a 2C draw from the batteries. If you're using ultra fires they are likely around 500mAh so more like 3C which is way to much.

Get these: AW IMR 18350 700mAh LiMN Rechargeable Lithium Battery
They can handle a 5A draw.
 
Those are out of stock :/

What about these: AW RCR123a Protected 750mAh Battery? I think RCR123a's are 16mm wide instead of 18mm, but a plastic sleeve should solve that issue, no?

Thanks,
Isaac

Also, could you say what those numbers represent? 2.1A is obviously the current I want across the diode, but where did 4.8V come from? and what is 2C vs 3C? Sorry, I don't know a ton about batteries. :/
 
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The C numbers:
General rule of thumb for standard Li-Ion is 2C max discharge current, where C is the value of the capacity of the cell.

IMR vs. ICR:
These letters describe the battery chemistry, cathode material, and shape. I denotes Lithium Ion, M/C is the cathode material, Mn or Co, and R denotes a round cell. Generally speaking, Manganese cathode cells are inherently safer, and can often supply more current without sagging. IMRs may have more than a 2C discharge rating, some as high as 10C, although at the cost of less capacity.

I'm with ARG. Easiest solution is to find a pair of IMR18350s. RCR16340 are ICR chemistry, and also will only handle 2C, i.e. in your case, 1.5A max.
 
wannaburnstuff said:
Did you mean 18350's? I don't see 18340's on that list which is why I ask. So I should get the IMR 18350 AW cells and they will handle my current needs?

Thanks,
Isaac
Click to expand...

Whoops yeah I meant 18350. I don't think there are 18340's. The 18350/16340 AW IMR cells will handle your current needs :beer:
 
I got the Titanium Ice host for 35 dollars shipped and after paying 130 bucks for diode+driver I just plain cannot afford to buy a new host. All the hosts that size I see are upwards of 50-60 bucks.
 
I have given up on the Titanium Ice host. I have a 2x 18650 being made by ehgemus and that will work splendidly methinks.
 
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