A question for the ECF foljs.

[SpectralWolf]

So I use sub ohm coils, I ordered some really nice 0.5 premade coils I check them all before I use them to make sure what level they are at and it is always in the 0.5 range. Now my batteries I use are AW IMR 18650 2000mah 10a is this battery Ok to use for my 0.5 ohm coils? I read a lot on them and as long as its 0.5 and no lower I'm at a safe level I just want your guys opinion.

 

[roxynoodle]

Ohm's Law: voltage/resistance = current

4.2v/0.5ohm = 8.4A

Technically you're within limits, but pretty close. I would rather see you use a 20A battery or higher.

 

[nyiddle]

Ohm's Law: voltage/resistance = current
4.2v/0.5ohm = 8.4A
Technically you're within limits, but pretty close. I would rather see you use a 20A battery or higher.

Yep. I'd recommend leaving plenty of "headroom" just to be safe.

 

[MrPlink]

Yep. I'd recommend leaving plenty of "headroom" just to be safe.

Especially if you are using a mech or regulated device that is capable of drawing much more than 10a.

Hypothetically, you really should be fine.
10a is a continuous rating, burst rating should be much higher, but they call them accidents for a reason.

 

[SpectralWolf]

I agree, I just ordered aw imr 18650 2200mah 3.7v 20a discharge. Will those be ok?

 

[roxynoodle]

I agree, I just ordered aw imr 18650 2200mah 3.7v 20a discharge. Will those be ok?

That should provide a good safety margin.

 

[SpectralWolf]

Thanks for the info

 

[kickflipsnnollies]

What kinda percentage do you guys recommend to leave for headspace?

I'm running a 0.5 ohm build on my Stillare and I only own 2 batteries - a MNKE 30 a and a red Efest 2000 mAh rated for 10 a. I try to stick with my MNKE as much as possible mostly because there's a very noticeable difference in performance, but it doesn't last all day and I have to switch to my Efest at some point while the MNKE charges. I know I should buy more better batteries, but cash flow is low so I'm stuck with what I have for now.

 

[MrPlink]

What kinda percentage do you guys recommend to leave for headspace?

I'm running a 0.5 ohm build on my Stillare and I only own 2 batteries - a MNKE 30 a and a red Efest 2000 mAh rated for 10 a. I try to stick with my MNKE as much as possible mostly because there's a very noticeable difference in performance, but it doesn't last all day and I have to switch to my Efest at some point while the MNKE charges. I know I should buy more better batteries, but cash flow is low so I'm stuck with what I have for now.

Again, if 10A is the continuous discharge rating you should be fine outside of prolonged auto fire or a short. If 10A is the BURST discharge rating (unfortunately efest isn't very clear or honest with their ratings) then you are really begging for trouble.

 

[JeremyR]

I recommend 50-40% headroom if possible for extra safety. With a max of 70-75% of amp limit.

Things will always happen... One way or another.
If there would be a short and your coil dropped to .04 you would be at 10.5amps. Coil ohms can fluctuate under high power, and your not monitoring the ohms like on a vv/vw. Testing on a meter will show cold ohms, under power it can change. It could actually drop to .48 or .45 under fire.

If it dropped to .03 by a short you would have 14 amps load.

If it's ready made with nores legs it's probably more of a risk they pop in an auto fire and possibly short lower than .5