When one looks at battery test charts, they don't even remotely support your claims that your arbitrarily-defined cutoff voltage is the right measurement. After that, you're just piling on nonsense.
SXmini Q Class Powered by YiHi SX450 chip
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When one looks at battery test charts, they don't even remotely support your claims that your arbitrarily-defined cutoff voltage is the right measurement. After that, you're just piling on nonsense.
It's simple math. To maintain any given wattage on a regulated mod, you must pull a certain amount of current from the battery based on its voltage. As voltage decreases, current increases. So, the lower you let the voltage get in your battery, the more current you need to pull to maintain the output wattage.
The mod's cutoff voltage is BEFORE FIRING. Even 0.01V above the cutoff voltage will fire on the SX mods. When you draw that much current, the battery voltage sags. I don't need to prove math, science, and physics to you - you can set your SX to 60W on a full battery, and watch the battery meter take a dive.
What you need to ask yourself is: If Yihi really thinks they can safely and consistently get 200 watts out of two 18650's. Then why aren't they able to pull 100 watts out of one 18650 in their SX Mini's? That's a rhetorical question, no need to answer.
So far as evaluating whether the product can perform what it claims, we only need to concern ourself with a charged battery and how it performs. So far as when the battery is below maximum charge, we don't know anything about how the product performs. For example, it may limit the maximum current draw below a defined voltage, just as other chips do.
Well, it's not so much a rhetorical question, as a statement built on false assumptions. A mod is not just its batteries, but also the wiring and the chip too. Those also have to be designed to handle the current draw at issue, which the SXM was not designed to do. It's no different than the DNA 40, which wasn't designed to handle as much current as one can obtain from an 18650. And lest someone tries to argue that the sx350j can handle 150W in dual serial 18650 configuration, so why can't it handle 100W in single 18650 configuration, that's because in serial configuration the voltage from the batteries is doubled - current draw remains the same.
That would have been a fair statement had YiHi not already stated multiple times in multiple places, their own math showing >30A draw, and "make sure you use a 35A battery" - I guess nobody let them know those don't exist, or they saw a photo of a "35A" Efest.
Don't you understand the chip has nothing to do with what the battery can supply it? The battery is the power source, it can supply what it can supply. The chips only function is either stepping up or down the voltage and current inversely. When one goes up, the other goes down.
Edit Another thing to keep in mind is chips aren't 100% efficient. Lets be generous and say the chip is 97% efficient. When the user dial up 200 watts, the battery would have to supply 206 watts to the chip (the other 6 watts are dissipated most likely in the form of heat by the chip)
Edit Another thing to keep in mind is chips aren't 100% efficient. Lets be generous and say the chip is 97% efficient. When the user dial up 200 watts, the battery would have to supply 206 watts to the chip (the other 6 watts are dissipated most likely in the form of heat by the chip)
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The sx350 is single battery or parallel only, or am I wrong? Pushing 3.2-4.2v to the voltages required for 150w+ might be difficult. I'm thinking that might be one reason, but I'm only guessing (and it's nowhere near an educated guess).
As for the pulsing over 150w, I really want someone to enlighten me on how that actually works and how/why it's safer.
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With some discussion we've had recently in the battery forum I'm really surprised that we haven't seen a serious accident with regulated mods yet. Put mismatched cells harvested from a laptop battery pack into a serious mod, push it into high wattages, and something bad is bound to happen. The mod can in no way know what the batteries are capable of so battery safety is equally important in regulated mods. I guess the magnetic battery doors will make outright explosions unlikely.Maybe people should wait and see what it is.
OMG, so much discussion with no knowledge of Design/intent.
Still waiting for a true report of a Quality Battery Venting in a quality Regulated Mod design.
Every report I have seen so far has been Mechanical + Stupidity = Boom!
So far
Honestly, Yihi ignoring Safetywe will see once they release Product and Details.
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My way of thinking is if a battery is rated at 20amp continuous current but 35 amp pulse current. Then pulsing at 35 amps won't be over the CDR of the battery.
The chip design determines the load on the battery, thus controlling the current draw. It then converts the power obtained from the battery to the appropriate power to be delivered to the atomizer. If the system is not designed to handle the current draw, such as with the DNA40, then it cannot use the full potential of the battery. That doesn't mean that pulling more than 40W from a battery is unsafe, it's just not what the DNA40 was designed to do.
Never met one vaper yet that vapes at 200watts. The power is nice because it ensures that you dont need to change your battery once a day. IF vaping a coil with Ni200, for instance, even at 40 watts, it lets you vape without feeling as if you are pushing that power.
Anyone know if or when this dual mod is due?
Anyone know if or when this dual mod is due?
Yeah, that's kinda what I was guessing. Doesn't seem all that safe though.
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That's correct. The main underlying issue is heat generated by the current within the battery. If you're pulling a constant current, then the CDR is the limit at which a sustained current draw won't overheat the battery. If you're doing pulsed current draw, then you can pull more current so long as your pulse is short enough to not overheat the battery beyond safe operating conditions. So long as your keeping the battery below a certain temperature, then you can do whatever you want within reason. If you want to stress the batteries beyond that, then you need active-cooling to keep the temperatures down.
I'm not talking about a DNA40. I was talking about how much power can safely be supplied by an 18650 battery. If they want to rate the mod on what it can do at 75% charged and above, that's their right. I just think it's deceptive at best.
It doesn't matter whether batteries are wired in series or parallel. When a two 18650 mod says it can supply 200 watts, that means each battery has to supply 100 watts (plus what's used as heat by the chips inefficiency). That can only be done safely if it has a certain charge remaining.
Example at 3.5V a battery has to supply 28.57amps to supply 100 watts (really more considering chips aren't 100% efficient, not to mention the voltage sag you get). That's all I'm talking about.
It doesn't matter whether batteries are wired in series or parallel. When a two 18650 mod says it can supply 200 watts, that means each battery has to supply 100 watts (plus what's used as heat by the chips inefficiency). That can only be done safely if it has a certain charge remaining.
Example at 3.5V a battery has to supply 28.57amps to supply 100 watts (really more considering chips aren't 100% efficient, not to mention the voltage sag you get). That's all I'm talking about.
Main thing I was saying is wait till the mod is released and we actually know what we are talking about before getting our undergarments in a bunch. Right now we have got virtually zero concrete information and we are arguing about it just for once it would be nice to wait and base things on fact.
We are all arguing here for nothing! A lot of people have been waiting for this, it's going to be a great mod. Just would have been nice if Yihi would have been a little more responsible with the marketing and made this a 150 watt mod. Witch would have been more than good enough for everyone looking to buy one After all how many people vape between 150 and 200 watts any way?
After all how many people vape between 150 and 200 watts any way?
No, that's not entirely correct. The pulse rating on batteries is very misunderstood. Every manufacturer has a different idea of what "pulse" means. What's the duration of the pulse, and how often over what time period? Heat is additive, and the more current you draw, regardless of the time period, the more heat is generated. Build up too much heat and the battery vents. I could make countless analogies to friction, objects through a flame, etc., but I think you get the idea.
Not only that, but if it takes up to 39A on a near-empty battery (at the mod's cutoff voltage) to achieve 200W, and the mod pulses, you're not getting 200W anymore! Let's say you have a 50% duty cycle - pulse ON time is equal to OFF time. Now you're only drawing 19.5A from the battery (which is 100% CDR on most 18650's). Your effective wattage is now cut in half, so you're really only getting 100W of constant equivalent power, not 200W. It's unlikely the duty cycle would be 50%, but it makes for a nice and clear example.
Mee tooI'll be watching this device but I'm pretty content with my measly 75W gear.
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