Why does battery affect performance?

[delinx32]

I have an aerotank running a 1.8ohm dual coil.

When I run it on my Itaste VV at 8w, it tastes burnt, poor vapor cloud and it gets hard to draw over time.

When I run this tank on my new evic supreme at 8w, i get an incredible vaping experience. Good flavor, great cloud, easy to draw.

When I run it on a standard ego 3.7v battery, there is a cold tinny taste to the vapor.

Why would the batteries at the same wattage cause the atty to perform differently? I would think the tank/coil would make a difference, but not the electricity delivery device.

 

[Rizzyking]

Its usually to do with how the power is regulated or if its regulated as to why the supposed same power setting delivers such variable results. Evic is regulated device as far as I know so supply's a steady even stream of power allowing the vape to be consistent. I'm relatively new into all this I'm sure you'll get better answers soon.

 

[cobaltxblue]

There are multiple possibilities here. First, you cannot rely on a power setting on a mod being correct let alone synced up in the power that they are delivering to a coil when talking about multiple mods/batteries. Another variable that is in play is the cleanliness of the contact between the mod and atomizer. Along the same lines is how strong/thorough the connection is, for example are they touching completely or just barely.

 

[GeorgeF]

It could be how each one handles the output voltage.
The itaste may by providing mean (or average), the evic may be providing RMS voltage. and the standard 3.7v battery is only giving you 7.61w (at least that is what the wattage calculates out to using ohms law).

 

[Sgt.Rock]

Don't trust the settings on your devices without verifying actual voltage output using a multimeter or some other measuring device.

Also, some batteries hold up better under load than others...

 

[rusirius]

I have an aerotank running a 1.8ohm dual coil.

When I run it on my Itaste VV at 8w, it tastes burnt, poor vapor cloud and it gets hard to draw over time.

When I run this tank on my new evic supreme at 8w, i get an incredible vaping experience. Good flavor, great cloud, easy to draw.

When I run it on a standard ego 3.7v battery, there is a cold tinny taste to the vapor.

Why would the batteries at the same wattage cause the atty to perform differently? I would think the tank/coil would make a difference, but not the electricity delivery device.

I'll just clarify a few points here. There are all sorts of things that can vary how much power is REALLY being delivered to the coil. One mod may have smaller gauge wiring (more resistance), one may have a different 510 connection that makes better or worse connection, etc. All of these things create resistance, and where you have resistance in a circuit you have voltage drop. So even if the mod is tuned perfectly to deliver a perfect 3.8V to your 1.8Ohm coil at 8W, the voltage that the ACTUAL coil sees could vary a fair bit. Let's say your Evic has a .1V drop, and the itaste has a .5V drop... That means the Evic is delivering 7.61W to the coil, while the itaste is delivering 6.05W to the coil... Now let's say that little old ego had a very bad 510 and you were seeing a .6V drop... If the battery is at 3.7V then it would only be delivering 5.34W... All of which are going to give you a different vape.

And that's not all. Your Evic might be calibrated to account for it's internal drop... So it may be delivering say 3.9V, which drops to 3.8V giving a solid 8V, or it could over-deliver and be giving you a vape higher than what you dial in. All just depends...

And yet it runs deeper. When you regulate DC there are different ways to do it. One way is to use a voltage multiplier. I won't go into details as to how this works since it's not important for this discussion, but the end result is a DC voltage that is solid. Just like a battery... In other words, if it's outputting say 5V, then the voltage is a CONSTANT 5V with absolutely no variation. Another way to do it is to use PWM or Pulse Width Modulation. So you ramp up the voltage to it's maximum value, for simplicity let's just say we ramp it up to 10V. Now we "pulse" the voltage in a square waveform to achieve the voltage we want. So if we leave it on 100% of the time, we are outputting 10V... If we pulse it on and off so that it's only on 50% of the time it's 5V... etc... So it's switching on and off really quickly and the longer it stays on versus off the higher the "effective" voltage your coil sees. But depending on the frequency the pulsing occurs at, the resistance and heat capacity of the coil, etc this will cause the vape to be quite different from a constant voltage source. 5V of constant DC is going to vape quite different than 5V of PWM at 20Hz and quite different from 5V of PWM at 20kHz, etc...

So the long answer is, yes, the power delivery device can certainly make a big difference on the performance of the vape.

 

[USMCotaku]

It could be how each one handles the output voltage.
The itaste may by providing mean (or average), the evic may be providing RMS voltage. and the standard 3.7v battery is only giving you 7.61w (at least that is what the wattage calculates out to using ohms law).

I don't know what the evic uses, but the itaste does use pwm, but doesn't use mean. In fact, the output frequency on the itaste vv is higher then most other pwm mods except for provari's, its one of the reasons the itaste vv and MVP are so popular, providing an incredibly smooth vape for the price point.

 

[DaveP]

rusirius nailed it, but I'll add some comment.

Your various VV and mech devices will all deliver a slightly different vape for all the reasons rusirius listed. There's the difference between regulation formats that can be DC voltage in a mech or PWM (pulse width modulation) in a mod by using MEAN (average) or RMS (root mean square) calculations to produce a voltage. Those are just high tech terms for how a variable mod using a regulator can deliver a variable voltage from a DC source using frequency pulses to vary the waveform, amplitude, and on-off time to achieve something that's similar to turning the voltage up and down. There's 33hz PWM, 66hz, and 800hz variable voltage implementations that I'm aware of.

The bottom line is that you can't really go by the number you see in a display. You just have to vary the power or voltage according to taste and remember which works for each mod. It's all about creating heat.

My Provari, my Sigelei Zmax V3, and my Eleaf iStick all work best at different settings. They aren't broke, just different in the way they produce the voltage or wattage output.

Phil Busardo explains it best by using o-scope pictures of the output from different mods. It's worth 11 minutes of your time if you are interested in why different mods work differently on the same settings. At the end of the day, all you need to know is how to set each to produce the vape you like. He ends it by saying that varying the voltage or wattage to get the taste you like is all you need to know how to do.

 

[IMFire3605]

The iTaste VV and MVP which use similar boards, only the VV is a stripped down version of the MVP board, Pulse Width Modulate at 33.3Hz like most of the Innokin products excluding the SVD 2.0 and the future MVP 3.0, also the VV and MVP are not generally the best or easiest 510 connections to work with, wether they output in RMS or Mean to get their PWM is uncertain. The Evic Supreme being a newer model and design PWM in RMS mode at probably a higher Hz factor giving a smoother more consistent vape, example a unit at 33.3Hz PWM Mean at 4v could mean it is attaining its max output of 5v in the case of the VV longer in its on duty cycle compared to the Evic Supreme which outputs a flat straight voltage, no PWM like the Provari does, the vape is smoother as the Evic Supreme puts out a straight 4v or whatever is set, the standard Ego battery, though it can handle the tank resistance, is just shy of the output the other 2 can attain.

Best advice is to manually adjust the iTaste VV to taste, probably going to have to set it into Voltage mode, start at 3.5v take a couple hits, to weak bump up to 3.6v take a couple hits, still to weak, up to 3.7v until you get it dialed in to not being scorched tasting, also remember in Wattage Mode, the VV goes in .5 watt increments compared to the Evic does wattage in .1 watt increments

 

[rusirius]

rusirius nailed it, but I'll add some comment.

Your various VV and mech devices will all deliver a slightly different vape for all the reasons rusirius listed. There's the difference between regulation formats that can be DC voltage in a mech or PWM (pulse width modulation) in a mod by using MEAN (average) or RMS (root mean square) calculations to produce a voltage. Those are just high tech terms for how a variable mod using a regulator can deliver a variable voltage from a DC source using frequency pulses to vary the waveform, amplitude, and on-off time to achieve something that's similar to turning the voltage up and down. There's 33hz PWM, 66hz, and 800hz variable voltage implementations that I'm aware of.]

You know, you popping in here just made me think of a perfect analogy...

Let's say Dave here is getting ready to play a song... Now as he's setting up his stack he realizes he has 3 different amp heads he can pop in there... One is an old fender tube amp, one is a new bogner tube amp, one is a marshall solid state amp. Now let's say all 3 of these amps are 100W... He plays the song 3 times, each time turning it to 11. D) Just because all 3 amps are 100W amp heads doesn't mean it's going to sound the same each time! Each time he plays it's going to sound different depending on which amp head he's popped in. Just because the power output is the same doesn't mean it's going to provide the same experience!

 

[DaveP]

You know, you popping in here just made me think of a perfect analogy...

Let's say Dave here is getting ready to play a song... Now as he's setting up his stack he realizes he has 3 different amp heads he can pop in there... One is an old fender tube amp, one is a new bogner tube amp, one is a marshall solid state amp. Now let's say all 3 of these amps are 100W... He plays the song 3 times, each time turning it to 11. D) Just because all 3 amps are 100W amp heads doesn't mean it's going to sound the same each time! Each time he plays it's going to sound different depending on which amp head he's popped in. Just because the power output is the same doesn't mean it's going to provide the same experience!

Yep! And in some circles the Fender tube head would win because it's Fender, tube, and old!

And there always the difference in biasing, preamp tubes, and tone circuits and effects loops. I remember reading about an extensive test where musicians and recording engineers were seated in a studio and were told to listen to the same guitar player behind a half wall through three amplifiers and determine whether each were tube or solid state. Almost all missed the mark on the one they determined to be a tube amp.

I play through a hybrid guitar amp these days. It's a Peavey Vypyr Tube 60. The front end is digital, with a 12ax7 preamp followed by a dual 6L6 output stage. I swapped out the 6L6's with a pair of KT88's. Both sound good, but I've convinced myself that the KT88's beat the 6L6's on presence, overall tonal balance, and feel. That may be hogwash, but it makes me happy when I play it!

Oh, and a clean car drives better.

 

[shortdraw]

That's a good analogy rusirius.

 

[USMCotaku]

Anyone got an old pioneer sx-1980 laying around to give me? No one wants that old 70's receiver anymore........
Sent with one hand, the other is busy vaping.

 

[DaveP]

And then, there's the common issue where some variable mods have only boost circuits and no buck circuitry. The Eleaf Istick is one of those. It can only boost voltages above the battery voltage level. It has no buck regulator, so you can dial down the voltage or wattage, but it will always deliver battery voltage as its lowest setting. If your battery charge level is at 3.7v, you can't get a vape less than 3.7v until the battery loses some charge. You can always boost it above current charge level, but not lower the output.

The other caveat is that it measures its output in MEAN (average) rather than RMS (root mean square), so you actually get a hotter vape than you dial up no matter what you expected as compared to RMS mods.

 

[rusirius]

And then, there's the common issue where some variable mods have only boost circuits and no buck circuitry. The Eleaf Istick is one of those. It can only boost voltages above the battery voltage level. It has no buck regulator, so you can dial down the voltage or wattage, but it will always deliver battery voltage as its lowest setting. If your battery charge level is at 3.7v, you can't get a vape less than 3.7v until the battery loses some charge. You can always boost it above current charge level, but not lower the output.

I'm not disagreeing with you, I've seen this said many times, but to be honest it just doesn't make any sense to me. I don't have an Istick myself, but I'd love to throw one on my scope and see what's going on. The part I don't understand is the istick is PWM. It doesn't need buck circuitry. With pwm I boost the voltage to whatever I want my max top be, lets just say that's 8V. Now I can generate any voltage I want between 0 and 8 by just varying the duty cycle. At 0 percent duty I have 0 volts, at 50 percent I have 4V (duty cycle is a little off if I'm doing rms because of the wave crest, but still I can generate any voltage I want from 0 up to my max. It just wouldn't make sense to not be able to go below battery voltage with a pwm device.

 

[USMCotaku]

A lot of the pwm devices lack the ability to "down step" below a certain level. The istick won't even let you set it below it's lowest setting based on what coil you are using. For instance my current kayfun build won't go below 6 watts/3 volts. It's a 1.5 ohm build.
Sent with one hand, the other is busy vaping.

 

[DaveP]

Phil Busardo explains it well and uses his scope to explain what's going on. The scope pictures of the voltage waveform with data start around 26 minutes into the video. When you see voltage on the iStick display, it's calibrated in MEAN rather than RMS, so if you are expecting an RMS approximation the vape will be hotter on the iStick at the same voltage compared to an RMS device.

 

[93gc40]

for the same reason a bigger or better motor affects the performance of your car.

 

[rusirius]

Phil Busardo explains it well and uses his scope to explain what's going on. The scope pictures of the voltage waveform with data start around 26 minutes into the video. When you see voltage on the iStick display, it's calibrated in MEAN rather than RMS.

No, I get it, I just don't understand why they wouldn't allow it to go slower. It's max voltage is close to 6 watts. In the first scope image shown you can see the duty cycle is close to 50% meaning it's on half the time and off the other half. But you can lower the duty cycle below that. If for example you set a duty cycle of 25% that would put you close to 1.5V.. doing so you can go all the way down to 0V. You see what I'm saying? That's the beauty of pwm. As far as mean versus rms, that's just a difference of how you calculate the duty cycle based on the voltage you want.

 

[DaveP]

I'm not disagreeing with you, I've seen this said many times, but to be honest it just doesn't make any sense to me. I don't have an Istick myself, but I'd love to throw one on my scope and see what's going on. The part I don't understand is the istick is PWM. It doesn't need buck circuitry. With pwm I boost the voltage to whatever I want my max top be, lets just say that's 8V. Now I can generate any voltage I want between 0 and 8 by just varying the duty cycle. At 0 percent duty I have 0 volts, at 50 percent I have 4V (duty cycle is a little off if I'm doing rms because of the wave crest, but still I can generate any voltage I want from 0 up to my max. It just wouldn't make sense to not be able to go below battery voltage with a pwm device.

I spent decades servicing complex machinery that used multiple point of need power supplies with multiple outputs. I'd just troubleshoot down to the board level in a failed PS and change the FRU. My initial electronics school taught us how supplies work and made us build and explain the circuitry during the learning process. In reality, all we cared about was that we could find the bad component and replace it.

Most of those were AC fed supplies with AC and DC outputs. Now, we are seeing battery operated devices with buck boost converters to compensate for varying input voltages. No longer can we count on a supply having a fixed input voltage if the voltage source is a battery.

Buck-Boost Converters

Buck-Boost Converters

A Buck-Boost converter is a type of switched mode power supply that combines the principles of the Buck Converter and the Boost converter in a single circuit. Like other SMPS designs, it provides a regulated DC output voltage from either an AC or a DC input.

The Buck converter described in Power Supplies Module 3.1 produces a DC output in a range from 0V to just less than the input voltage. The boost converter will produce an output voltage ranging from the same voltage as the input, to a level much higher than the input.