Quick question on voltage,

[georgini]

Building something that looks like a juice box (radio shack black box) with 4 AAA batteries. If i put 4 new batts in (alkaline) will i fry an atomizer?

It's been working fine with 4 "almost dead" batteries. At rest they measure about 5 volts and then when in use about 3 to 3.2 volts.

The 4 new ones measure about 6 volts at rest.

Also thinking I should go with 3 AAA batteries?

I guess I'd like to know the best combo of AAA or AA, alkaline or rechargeable options.

There's so many threads ont his and I've read hundreds, hard to decide! thanks,

 

[secondson2929]

In my magnum I run about 7v fully charged. I have not had a problem. Just make sure you keep the atomizer wet. Lots of voltage and a dry att is asking for trouble.

 

[georgini]

thanks, I'll try out the 4 new AAA alkalines and report back. Right now I'm waiting for some jbweld to dry on it.

 

[Rubberjohnny]

I have made quite a collection of "battery box" mods over the last few months and tried a whole range of battery options.
Three (4.5v) or four (6v) in series alkaline battery models have both performed well, the four battery option (irrespective of being AAA, AA, or C) giving more vapour and lasting longer.All variants were "safe" with atomizers.
Results from re-chargeable NiMh batteries have been mixed to say the least.All sizes of NiMh batteries are rated at 1.2v so four in series should (and on meter does) give 4.8v. Now since atomizers are made to run on a similar voltage this should be the perfect set up. However, many burned out atomizers later I now only use three (3.6v) in series to be safe. Interestingly you can make four battery mods "atomizer safe" by using three re chargeables and one alkaline.Hope this helps.

 

[georgini]

That does help quite a bit. I put 4 fresh alkalines in this AM, didn't fry anything, Seems to drop down to about 5v when using. Glad you mentioned about the 4 rechargables killing atomizers because I would not have even thought twice about trying that setup.

 

[kinabaloo]

Rubberjonny - Interesting. I want o doubt what you say as it sounds illogical, and the sample size is small. But there might be something in it. And my guess would be that the NiMH batteries can provide high current more instantly; this heats the coil too fast (faster than necessary, 0.2 secs to reach 1 amp would be fast enough) causing greater mechanical stresses through expansion. This being so suggests we might add a capacitor across the load to dampen this as a measure to extend atomiser life, regardless of batteries used this could be a useful thing to do.

 

[georgini]

I wish I had a schematic withe a capacitor in it. I think it would help smooth out the performance of the unit. I believe you are right about the NiMH batteries. They perform better in high current applications, i notice this with cameras and using a flash.

 

[Vince1]

Has anyone tried the 4 battery setup with 1.2v lithium batteries? It's my understanding these have been used successfully.
http://www.batteryspace.com/index.asp?PageAction=VIEWPROD&ProdID=2970

 

[Rubberjohnny]

I agree with your thoughts regarding immiediate high current from NiMh since the "burn out's" are instant and invariably the break is where the coil is conected to the posts either side of the ceramic pot. I have had success fitting a resister in series on the positive side of the circuit but a simpler way of making a 4 battery system safer is to use 2 or at most 3 NiMh batteries and 1 alkaline. This combination seems to dampen the immiediate load and certainly saves atomisers from instant burn out.

What we all need is a much more robust wiring circuit within the main body of the atomiser with the nichrome wire coil being a replaceable (say "push fit") item.Not only would this greatly reduce cost but would allso solve the problem of continuing to use a bad tasting atomiser due to burnt/degraded coil filling.If the contact points within the ceramic pot were reasonably sturdy posts then a replacement coil, together with mesh bridge would be the only disposable part of the e-cig.

 

[kender]

a small induction coil might be good for limiting the current flow but keeping the voltage the same.
If anyone wants to try just take the + wire going to the atomizer and wrap it around a small nail or screw about 5 times and that will limit the power draw.
I only have one atomizer right now (please don't break) but when I get some extras I'll try it.

 

[ratfink]

I wish I had a schematic withe a capacitor in it. I think it would help smooth out the performance of the unit. I believe you are right about the NiMH batteries. They perform better in high current applications, i notice this with cameras and using a flash.

Basically what you would be doing it decoupling the line. A couple uF capacitor running from supply to ground would do what you are looking for.

 

[ratfink]

small induction coil

The problem with induction coils is that when the magnetic field breaks down you get a voltage surge across the load, which is probably not the healthiest thing for an atomizer.

 

[kender]

Ratfink your right about that. I normally put a diode in reverse to handle any back emf that occurs.
I wish I had some atomizers to spare to see what is causing them to fail. It does sound like full power to quickly. The cap would work also, anything to slow the initial power flow.