DNA Battery Life: Kanthal vs Ni200

[liquid_strat]

I've noticed that nickel builds provide a satisfying battery life. I can get through most of the day without needing to change batteries. With Kanthal builds, battery life is considerably less. As an example @ a 30 watt setting with the DNA40 showing a full battery charge: I can remove the atty built to 0.15 ohms using nickel and replace it with a Kanthal built atomizer and see the battery indicator drop at least a 10 - 15% after the first fire. The Kanthal build will continue to drain the battery in a similar fast manner.

What I'm looking for is information on how the dna 40 in temperature mode distributes power or uses available battery power. From what I have come to understand, regulated chips like the dna devices, for a given wattage setting, draws the same amount of power from the battery regardless the resistance of the atomizer. The chip's power requirements, at a given wattage setting, being independent of what is going on inside the atomizer.

(reddit explanation)
http://www.reddit.com/r/electronic_...nk_its_time_to_bust_a_myth_about_the_battery/


So at 100% chip efficiency this would be 30watts / 3.7v (nominal battery voltage) = 8.1amp draw (always, regardless of coil resistance).
DNA40 @ 92% efficiency 32.6watts / 3.7v = 8.8 amps (battery drain)

Something else must be going on with nickel and temperature mode.

 

[dr g]

Well the reason for the immediate dropoff is the change in draw on the battery at end of firing (when the battery is polled). TC is likely throttling back at that point while non TC is still firing at full wattage.

After that it's a question of the performance of the respective builds. In general it does seem that you can save energy when TC automatically throttles back power significantly. But if you have a really power-hungry build, it won't get much more life since it will be running at max wattage all the time.