Regulated battery drain infograph

Also remember in series a .5 ohm coil with fresh batteries will get you 140 watts. Enough watts to power a 42" tv.

Eek!

You are right - I didnt do the power calculation in my example above.
8.4 volts and 0.5 ohms
P=Vsquared/R = 141 Watts

It's highly unlikely I will ever be attempting that!
 
Don't forget you can also time volts by current :)

But yea I don't see how anything above 50 watts can be enjoyable if I'm honest. Also I find the difference between 10 and 15 watts to be bigger than the difference between 15 and 25 so it's also a huge sacrifice in terms of battery life even if you do enjoy it.
 
Yes @Andre, you are correct, to explain; power (P) is the product of Voltage (V) and Amps (I), therefore the equation: P = V x I

For illustration purposes we will use 4 Li-po batteries fully charged at 4.2V and each have a discharge current capacity of 10A

when batteries (B1 to B4) are connected in series, only the voltage increases; Vtotal = V1 + V2 + V3 + V4 = 16.8V, but the total current is limited to 1 battery's capacity, due to the fact that this current flows through all 4 batteries. Thus, in this example we will have a total power of 168W [ 18.8V x 10A] at our disposal.

when batteries (B1 to B4) are connected in parallel, only the current capacity increases; Itotal = I1 + I2 + I3 + I4 = 40A, but the total voltage remains as that of one battery. Thus, in this example we will also have a total power of 168W [ 4.2V x 40A] at our disposal.

The main difference between our series and parallel connected batteries example are:

Reference // Series connected // Parallel connected

Voltage // 16.8V // 4.2V
Current // 10A // 40A

* If the same resistive load (coil) is connected to both circuits, the batteries connected in parallel will theoretically provide 4 times the vape time than those connected in series

e.g: Coil resistance (R) = 2.0 Ohm

Series connected: I = V/R, = 16.8/2 = 8.4A
Parallel connected: I = V/R, = 4.2/2 = 2.1A
 
Am I understanding this correctly? The Heatvape Invader, if in series, will provide more power but the battery life (mAh) as if just one battery? If in parallel the power will be as if one battery, but the battery life of all the batteries? Does not sound right if @GerharddP got 4 days of vaping from it?
vqyQpLk.jpg

Ok im going to try and explain this, we in the energy efficiency industry regard pwm as the san grial of energy saving. So what happens in the heatvape is that the power to the coil is "made" and "broken" at a steady frequency. Think about it this way, your energizing the coil and switching it of very fast but the coils physics allows it to stay at "vaping" temp in the off times because it hasnt had time to cool down. This means that a 1 second vape at what we call a "50% duty cycle" the coil has only "seen" a half second of active power. Thus the true power usage has been halfed yet a full 1 second off apparent power was used by the user. This means that for every second of a true power usage you are only using half of that so you effectively double the bat life by doing that. Add the fact that i used low drain and high capacity samsung bats from a laptop battery and i could vape for that amount of time.
 
Don't forget you can also time volts by current :)

But yea I don't see how anything above 50 watts can be enjoyable if I'm honest. Also I find the difference between 10 and 15 watts to be bigger than the difference between 15 and 25 so it's also a huge sacrifice in terms of battery life even if you do enjoy it.

I agree fully, with my new sig at 100w its like sucking a active volcano, BUT you buy a ferrari because you have the abbility to go fast then. Whether you enjoy it or not is peronal opinion but i bought it because it allows me to vape at "mech" power safely and to cloud chase with zero nic unflavoured 90vg/10pg juice and 100w wich is almost impossible with a mech by the way.
 
100w wich is almost dangerous and silly with a mech by the way.

Fixed :) Would you say that vaping at 100W is twice as good as 50W though? ;) For half the battery life, IMO it's not worth it
 
Fixed :) Would you say that vaping at 100W is twice as good as 50W though? ;) For half the battery life, IMO it's not worth it

No like i said, I dont enjoy it hence the volcano comment but i do love clouds. I actualy use it to test smoke detection systems sometimes that i integrate our systems to. So for me its fun not pleasure and i never said its safe in a mech, exactly why i went the regulated route
 
I wasn't suggesting you meant it's safe - I've just seen folks fire 0.15ohm coils on VTC5s. Pretty brave - don't think it's smart though.
 
I wasnt gunning you. Just clarifying. I would never go below .3 on a mech because people put to much trust in the 1 in 1000 bats tested at the factory. You might have a dud or a internaly floating short bat that only needs a bump to set it off. People unfotunately believe what they read without using common sense. The fact is that i use bats to about 75% of their rated achievements as and when i can. Plus i test each bat even if new with some sofisticated equipment before using or charging them.
 
@johan
Everything I read last night whilst trying to find an answer to runtime on series vs parallel made the claim that supposing you using two of the same batteries in each configuration you will get twice the runtime on parallel. For example 2x18650 Parallel
vs 2x18650 Serial = double runtime.

In your technical post you worked out 4 times runtime over serial, why is this?
 
@johan
Everything I read last night whilst trying to find an answer to runtime on series vs parallel made the claim that supposing you using two of the same batteries in each configuration you will get twice the runtime on parallel. For example 2x18650 Parallel
vs 2x18650 Serial = double runtime.

In your technical post you worked out 4 times runtime over serial, why is this?

In the example of my post 4 batteries were used.

your question/example:

if all is even (exactly the same coil resistance), in parallel mode you have twice the "runtime" (i.e battery 2 x 2000mAh = 4000mAh). In series mode, you have double the voltage but only 1 x 2000mAh - because current flows in series through both batteries.

This guy illustrates serie & parallel differences very well imo:



Hope this address' your question.
 
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Thanks that helps.
In the example of my post 4 batteries were used.

your question/example:

if all is even (exactly the same coil resistance), in parallel mode you have twice the "runtime" (i.e battery 2 x 2000mAh = 4000mAh). In series mode, you have double the voltage but only 1 x 2000mAh - because current flows in series through both batteries.

This guy illustrates serie & parallel differences very well imo:



Hope this address' your question.
 
@johan
please can you explain if stepping down 7.4v to 4v will help the heatvape to last longer than half of a patellel setup?. Thanks
 
need to find max output current on this CNA30 chip, I think? That will be load right?
 
@johan
please can you explain if stepping down 7.4v to 4v will help the heatvape to last longer than half of a patellel setup?. Thanks

Yes it will if the coil resistance is the same, however I must ad that I don't know the "heatvape's" circuit topology - lets look at it this way:

  • Batteries = 4.2V // 2000mAh
  • Coil resistance = 1.5 Ohm
  • Supply voltage (Series) = 8.4V & 2000mAh
  • Supply voltage (Parallel) = 4.2V & 4000mAh
  • Watts if Series connected: P = V2 / R .... (8.4 x 8.4) / 1.5 = 47.04W ... (I = 5.6A)
  • Watts if Parallel connected: P = V2 / R .... (4.2 x 4.2) / 1.5 = 11.76W ... (I = 2.8A)
  • Approximate continuous vape time when Series connected: t = Ah / I ... 2/5.6 = 0.36h or 21.6 minutes
  • Approximate continuous vape time when Parallel connected: t = Ah / I ... 4/2.8 = 1.43h or 1 hour and 26 minutes

If we however vape at exactly the same wattage, i.e 20W
Approximate continuous vape time when Series connected:
  • I = W / V ... 20 / 8.4V = 2.4A
  • t = Ah / I ... 2 / 2.4 = 0.83h or 50 minutes
Approximate continuous vape time when Parallel connected:
  • I = W / V ... 20 / 4.2V = 4.8A
  • t = Ah / I ... 4 / 4.8 = 0.83h or 50 minutes
It seems complex, but it is not - just print this ohms law formula wheel out and work through your own examples.

Ohms-Law-Formula-Wheel.png
 
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need to find max output current on this CNA30 chip, I think? That will be load right?

No, load is your resistance placed on the DNA 30 output (the coil resistance). The maximum output current (A) will give you one of two numbers/values to calculate your minimum coil resistance within a given voltage range - look at the Ohms Law formula wheel.
 
If we however vape at exactly the same wattage, i.e 20W
Approximate continuous vape time when Series connected: 50 minutes
Approximate continuous vape time when Parallel connected: 50 minutes

This is why I stick by my opinion of good batteries are key to a good vape! Devices can only be so (in)efficient but a good battery can add 20% extra battery life.
 
This is why I stick by my opinion of good batteries are key to a good vape! Devices can only be so (in)efficient but a good battery can add 20% extra battery life.

I agree 100% and must add, that those calcs are pure theoretical, in real "vape" life we only utilize approximately 25% at most of the battery's capacity, as we replace them long before they are depleted.
 
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