Sorry to be stupid newbie but I have tried to read as many posts as i could find on this subject and still don't understand.
So what is the difference between a black AW Protected 18650 2200mAh and a red AW IMR 18650 1600mAh
I am using a Provari around 4.8volts mostly.
Yeah can be confusing. The black are the IC (integrated circuit) protected kind, and the red are "safe chemistry" unprotected "high drain." Your next question will probably be which is best...
Read this again...
See full posts Originally Posted by AriM in http://www.e-cigarette-forum.com/forum/requests-opinions-reviews/255646-aw-vs-trustfire-18350-battery-battle.html
* "AW batteries are not made in the USA. All AW branded batteries are assembled in China, using mostly Panasonic (Japanese) Cells and Japan made protection PCB's (unles they exclude PCB protection). I have tested Virtually every brand of battery on the market, using proper lab equipment (charge discharge load tests as well as oscillograms under switching and constant loads) and the AW batteries I have had in the lab test far and above any other brand I have had on the bench. To be fair I should mention that there are some custom/exotic cells and packs I have tested that are head and shoulders above anything AW offers, but they are not readily available...and certainly not in the realm of sanity (in terms of cost). Also many of the more exotic battery chemistry/compunds are HIGHLY dangerous when they go into thermal runaway, and you most certainly would NOT want them anywhere near your mouth when they explode.
Now it's safe to say that the TrustFire, UltraFire, Tenergy brands are adequate and acceptable. They will work, and you will get vapor, but they all suffer from varying degrees of drop out voltage (parasitic voltage drop under load). Of course ALL batteries suffer some form of drop out (at least anything that will fit in a PV and is in the realm of sane cost). My testing shows, however, that AW batteries (generally) have FAR less drop-out voltage...when comparing apple to apples.
I am dramatically understating the varying chemistry/compound of each unique cell....but I can say that as a rough generalization,
AW's outperform the other common brands. I can also say that generally "IMR" AW's are NOT worth the hype they are built up upon. I much prefer the AW IC line. There is no real benefit to the "high drain battery". Yes there is a nominally "better" discharge curve over the life of the cell, but it is hardly noticeable on a HV mod and you do give up the benefit of under-voltage protection. Which, IMO, is the single most important characteristic of a Lithium Chemistry battery. Over discharging a Lithium battery will degrade it's life, and in most cases destroy the cell. All of the above holds true for ANY Lithium chemistry....including "LiFe", "LiION", "LiPO", "LiCo", "NNP" (you get the idea)...
Also you ask which cell "holds charge the longest". The answer is not so simple. Holds what level of charge? Some batteries will give you a specific voltage over the life of the cell, which will dwindle down to virtually "unusable" current availability...even though the cell is showing a nominal voltage of 3.2-3.4 volts. What really matters in a cell/battery is what will give you the most consistent performance over the longest period of time. If that is your concern then I can tell you that you will be best off with the AW IC 18500 (if you are looking for the best balance of size, capacity and potential discharge current). I am staring at a few of them right now (there is technically no IMR 18500...it would be an 18490...since it's a bit shorter). I personally wouldn't recommend or use anything else for a small 3.7v PV (unless money is no object).
Also...all of this information is splitting hairs, because to really answer the question truthfully a person would need to test a specific cell on a specific device in a specific situation. I suppose there is no "best", just what is more appropriate for your needs.
Hope the onslaught of information isn't too lengthy, and if anyone does bother to read through it...I hope it helps.
P.S. I was able to test a MASSIVE difference in drop out voltage between trustfire/ultrafire/tenergy 14500's and aw IC 14500's. A difference of 1.72 volts under heavy load (running a pair on various electronics packages).
* "The are some other key factors in battery performance (that I left out, for the sake of brevity). Like recovery voltage.
Most of the "high drain" batteries are design to sustain HEAVY loading for long periods of time (think high wattage flashlight). Keep in mind, most of us don't fire an atty coil for longer than 3-10 seconds (yes I know, I know....MOST of us). So the parasitic draw of a decent cell is minimal. Then when you let go of the button, the cell "recovers". I wish I could post an oscillogram so you guys could see this happen in real time. It's fascinating to watch what happens on the scope when you fire an atty. The level of complexity that is occurring is phenomenal."
* "I have been testing high performance batteries for the better part of 15 years. Way before there was any commercially available PV's. I can tell you, without a doubt, that the hype is well deserved. I have seen some catastrophic failures of poorly designed batteries....and it ain't pretty. I have watched thousands of dollars of electronics go up in flames. Thankfully I have never seen anyone get hurt....as we all knew what was going to happen when we were doing these tests, and when we weren't sure...we stayed FAR away from the test area.
ANY...I repeat ANY battery can become dangerous. If a cell is handled poorly, designed poorly, or it's protection fails...it basically becomes a bomb. At the very least you get off-gassing, and let me tell you breathing in fumes from a battery venting is not at all pleasant.
So here comes the part that is relevant. If you abuse a battery (some people are just asking for trouble) it will fail. The level of severity of that failure runs the gamut....from a battery that ceases to function...to quick limb removal. Again it all depends on the power of the cell, and how much stored energy needs to be released when the cell goes into thermal runaway.
On that note, I do have to say that the "battery industry", as a whole, has done a remarkable job in designing proper protection for cells. Am I saying that it's impossible to get hurt? NO!!! However one could argue that an idiot with a butter knife can be dangerous. It's like anything else. Treat the battery with some common logic...do your homework...and don't stab 4kw lithium cell array with a fork (just to see what will happen).
ANY battery can be dangerous, and well designed, well protected batteries can be very safe. To answer bluntly...there is NO "safe-chemistry" battery. Some chemical make-ups are just "safer" than others.
It's so difficult to make blanket statements or generalizations with batteries/electronics. It's all so specific. I can assure you though, that the laws of physics remain constant on Earth (at least for now). If you try to defy those basic laws, you will get hurt...or at the very least learn an expensive lesson.
I for one don't worry about the safety of the batteries I use in my PV's...as I have done my homework and have raw experience and data to predict what should and should not happen. I do have great concerns over others safety though...especially people who are sold "fake" xyz cells. It is utterly shameful for someone to go out and sell unprotected Lithium-Ion (and let's not even get started in Li-Poly) batteries as "protected". That is a REAL danger and it's very hard for the general public to know what is and what is not safe.
Man talk about me being on a soapbox. Sheesh. I am really glad you brought up the issue of battery safety though. It's very important (in my opinion) and I am more than happy to lend any information I may have about the subject. I hope I don't come off as a know it all in the process...because I am still learning about these things everyday. I am always open to ANY legitimate data that shows a conclusive result. Science begins with an open mind....
P.S. I am doing an AW LiFePO vs. Tenergy LiFePO shootout over the next few days. If anyone is interested in the outcome feel free to PM me."
* "AW's are also assembled in China....and also use Panasonic cells. Not trying to ruffle anyone's feathers, but you can get good cells from the same company that gives you "crap" (and Vice-Versa). Trust me I have seen some pretty interesting problems with certain AW cells and some astounding results from $1.79 Alibaba special generic cells. Each cell is unique, what sets the standard is the quality control and care in selecting the cell for a premium brand.
The problem I have found with trust fire, ultra fire, Tenergy, batteries is not the cell itself, but the protection PCB, and not so much the protection PCB, but the anemic wire they use to connect the PCB to the positive terminal.
Surprisingly the raw cells are only made by a few manufacturers and everyone just re-brands them.
If you want truly astounding cells....go buy a pallet of Panasonic NNP Lithium cells, and then run each one through a 10 cycle charge discharge load test, record the data, and pick the cream of the crop. Add a $1 protection PCB and put gold shrink wrap over them, and sell them as the greatest thing since sliced cheese. The problem is that you will wind up with a few thousand lesser quality cells, that have no place in your premium brands shrink wrap. You could just go sell those ("binned" cells) to Braun, for use in electric razors. At least that is what everyone else does."
* "What load are you presenting to the batteries?
What is the rating and quality of the switch/wiring in the mod?
What kind of charger are you using?
What are you vaping habits? I.E. how long is your average "drag".
Do you take more than 2 long drags in a 10 second period?
What I was trying to get across earlier, is that there is no way to generalize and say this or that is "better" or "worse". I would have to do some math, and calculate the load/discharge current needs of your situation.
Voltage drop off is not really relevant, when it comes to batteries. Especially in an unregulated electronics package. What is relevant is "drop-out" voltage under loading, as well as the ability to deliver a specified current over the charge life of the cell.
This is a VERY complicated topic. I am happy to help explain it (to the best of my abilities and level of education), but it is very specific.
For example. I build my own VV mod (and so do a few others). Which use current sense technology, to compensate for loading. So in that case a battery is a battery. Just as long as it's safe and the pack voltage never drops below 5.5 volts. I use a 2 cell configuration, at 3.7 volts per cell. So each cell would have to drop to below 2.75 volts, to see any current limiting in my electronics. That is well below the threshold of my lockout (which is 5.5v +/- 5%...with a time delay of 60ms). For anyone having a question about those numbers...yes my electronics package delivers greater than 95% efficiency. Please don't take that as a rude or snide comment (maybe a bit boastful), as it's not meant that way (us engineers don't have great people skills).
Now as far as a "mechanical mod" is concerned. As long as the wire/switch used in the device, is not limiting current (trust me they all do to some extent) then battery "quality" does become an issue. When you fire the coil, the battery begins to suffer from voltage drop out. Meaning that as the load is presented, and the cell is asked to provide on demand current...the voltage must drop to compensate for the requested current. There is no way to make a battery small enough, and cheap enough to fit in a PV (yet) that does not suffer from this phenomenon. So let's say you have a 3100mah AW nnp 18650 (great battery by the way). Even such a robust battery can really only provide around 3 amps of current, at FULL peak voltage. That amount dwindles as the nominal voltage goes down. So each time you fire the coil, the battery will be able to provide less and less current. Since ohm's law is a fixed ratio, the current availability MUST drop to compensate for the drop in voltage (it's called parasitic loss). Therefor 3100 mah is a useless figure. It only states the current availability of the cell at peak voltage (roughly 4.1v). Since a LR 306 (1.5-1.7ohm) is asking for around 2.3 amps (2300 ma) at 3.7 volts....well you can see the issue. The available current will begin to drop the nominal voltage as load is presented. The same atty is asking for 2.5 amps at maximum capacity (4.1v).
To answer this you would have to plot the voltage discharge curve over the current demands of the atty over the charge life of the cell. This is extremely complicated non-linear algebra. There are machines that do this for you (it's how I test my cells). Doing the numbers by hand, or trying to explain how to do the equations here on ECF would be a futile effort. Not because you guys aren't smart, but because I am a bad teacher (engineers curse).
Voltage stability is a myth. You simply will not get it in a "mechanical" mod. I mean you could, but you would wind up with a NASA sized bill, and the device would have to be suspended in liquid nitrogen. There will be voltage drop out at every point in the device. The spring, the body, the switch, the wiring, the connector etc....
The quality of the connections is crucial, and so is the material make-up. This is really why AW cells are "better"....
1. hand selected "cream of the crop" Panasonic cells.
2. Quality protection PCB
3. Properly isolated wire connecting the pcb to the cell (this is the most important part).
The wire that AW uses is wrapped in Kapton tape, and uses a silicon dielectric to isolate it from the body of the cell. I know it sounds simple, but it's always the simple things that make the biggest differences. This wire is puncture resistant. Which makes the cell that much safer. I can go into more detail if anyone is interested....and yes I have a stake in AW batteries, as I recommend and sell them. So take that for what it's worth. (Trust me there is a reason I choose to sell AW and recommend them....I have done the testing, and have the data to back it up).
Is AW never going to give you a "dud" cell? No way. You will get a few "crappy" cells per lot. That is just the nature of the beast. I personally verify all of the cells I use/sell...by running a charge/discharge/load test, and graphing the results.
Is trustfire/ultrafire/tenergy always going to give you "crap" cells? No way. I have some of these brands of cells in front of me and they are just fine on the scope. HOWEVER....these brands use an anemic wiring methodology to connect their protection PCB. I have seen some ultrafire batteries fail just touching the wire (under the shrink wrap). Does that make them less safe? I don't know....how abusive are you towards your batteries?
What I am getting it is that the raw cells are the same (or pretty darn close). However if the PCB/wiring is limiting the cells performance, that is a problem. That is why you will see higher drop out voltage on the non AW brands. It's not the cell, it's just the fact that they are trying to put 3 amps of current through a 28ga wire. Sorry but UL/CE electrical specs say that the minimum wire gauge for 3a is 17ga. (
American Wire Gauge table and AWG Electrical Current Load Limits with skin depth frequencies read for yourself).
I could go on and on about this for pages and pages.....I hope my explanations are concise and usable. If not I will try my best to revamp some of the points. Like I said I am an engineer, not a teacher....and my people skills are "crap" So if I am not articulating these topics well, please let me know. The scope of this topic is HUGE, so it will be hard to give fair answers....
Thanks for reading and I am always happy to lend whatever knowledge I can....."
