How does a 6v 4a boost driver affect the amp draw from the battery? CDR awareness!

Batteries and Chargers Rechargeable Batteries
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Hi all! As I’m continuing to learn more about the fine art of flashlight life, and using the right battery for the right application, and doing potentially weird things… I’m wondering how different drivers affect the application of CDR ratings.
Primarily this curiosity applies to my 18650 batteries as they don’t have as high of CDR’s as 21700.

I put an SFT70 with a 6v 4a driver in a convoy S3 host (I tried it first with a 6v 5a driver but that was just more than was necessary for the small host and usage) and by golly, I’m really loving it! It has become one of my favorite edc lights.

I want to make sure I’m using the right battery for this light, and so I want to understand better if there is any conversion necessary to know how many amps are being drawn from the battery with a 6v driver as opposed to a 3v driver. Am I still just looking at a 4 amp draw? Or would it be an 8 amp draw if it’s twice the volts?

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A 6V4A driver will draw around 8A from a single 3.6V 18650 NMC(A) 18650 cell.

What truly matters is the power draw from a driver. A 6V 4A driver will ask around 24W from a battery, or around 8A if we’re conservative with our calculations.

My recommendation would be to pick a cell that has a continuous discharge rating (CDR) of 1.5x to 2x more than the max current draw of your light if you want peak performance, keep your cells healthy and keep full output down to lower voltages.

For your battery, a 12-15A capable 18650 would be your best bet, so something like the EVE 30P or Molicel P30B would be a great choice.

1 Thank
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Groovy, thanks!
I have an M35A in it now, and was thinking that perhaps it should have a P30B instead, thanks for confirming that!
I rarely use it on high, but it’s good to have full potential available.