"Smart batteries" - is this how they work?

[Papa Lazarou]

I've seen some companies (mainly on the M4xx series) claiming that they have "smart batteries" which don't allow the atomiser to operate when the cartridge is empty. It seems to work - my Evo and M401's when they are very low on liquid seem to only allow the LED to light up for a second or two before shutting off the power.

I often wondered how this worked. This is just the way I am, it's not a big deal or anything but I like to know how stuff works!! There is no obvious "sensor" connection or anything else that would control this. So how does the battery "know" that the atomiser is dry?

The other thing that got me thinking on this is I've seen similar behaviour with other e-cigs - some DSE models and the Joye 510. The common thing about them is they all have these "electro magnetic" switches, which as I understand it are basically just some sort of microphone.

Now we know these types of switches are sensitive to sound and this brings some problems. These e-cigs are sensitive to deep bassy sounds which can cause them to switch on in your pocket in some situations.

My theory is that this is exactly how the sensor "knows" when the atomiser is dry. Basically, I think that the sound produced by drawing through a dry atomiser is different to drawing through one thats wet. Its very obvious in extreme cases (flooding) because the atomiser makes an audible gurgling sound as you draw through it. But even when its not flooded, its still going to be gurgling in a small way which is going to be detectable by a sensor. I would guess that the sensor could be tuned to shut off when the gurgling sound stops.

Does this sound likely or can anyone think of another explanation?

Thanks

 

[Vince1]

Possibly a sensor that detects increased resistance for a wet coil opposed to a dry one.

 

[spradling]

I don't think it would work that way (hearing for dry atomizer), but I have no idea how it would work.

The electro-magnetic batteries have a very nice draw, but the sensitivity is a pain, you have to unscrew it when not using it so it doesn't active (not when it's laying on a table, but when your walking or in the car). And in a club it's unusable! Battery doesn't stop flashing, even in my pocket, until I step outside away from the loud music. It's hard to smoke in the club because it's activated all the time, you have to screw, puff, unscrew or else the atomizer is going to burn.

 

[puff-puff-pass]

Possibly a sensor that detects increased resistance for a wet coil opposed to a dry one.

Thats where i would put my money.

 

[bizzyb0t]

Possibly a sensor that detects increased resistance for a wet coil opposed to a dry one.

I believe this is the answer as well.

 

[taz3cat]

Those new battery's are so smart they don't work worth a hoot. It's not how they work, but do they work.

 

[jimgman]

yes, i also beleive it is resistance, and also why so many had problems with the em-901's which is why they fell off the map. they had such little resistance they they were extremely hard to get lit or keep lit. i got it to work decent with some tweaking and flooding, but the draw was so light that they wouldnt activate for more than a second or 2 often. i also think they got better as they broke in(gunked up for lack of a better word), but most people instantly wrote them off as bad/defective.