Are you done stocking up?

[englishmick]

Yup. The inconsistency of opinions regarding storage temperature is why I decided to do my own testing. Some people say there's no benefit to cooler temps, others do. Who are you gonna believe?

Looking forward to your results. An actual test would make your opinions more convincing than other opinions.

And if you put it on YouTube I would know it was true.

It's not the expense of batteries that worries me; it's availability. Most of the big-name manufacturers are trying hard to keep loose cells out of the channels that we buy them from. I don't want to be in a position a few years from now where I need some "fresh" ones and the only ones available to buy are re-wraps of uncertain quality. I'd rather stock up on known-good cells when they're available and determine the best way to store them.

Actually I bought a bunch of batteries a year ago and stuck them in the fridge, partly based on something you said about it.

Bit of anecdotal "evidence". I got a couple of 18490 AWP's many years ago for my first Provari. Stopped using them shortly after when I got extended caps for 18650. Last year I got a battery tester and dug out those 18490's, they seemed to be in really good shape. So did the 18650 AWP's which were also old. I had quite a few 18650's and they got lightly used, the 18490's didn't get used at all.

What I take from that is batteries can potentially last a long time. To some extent it's use not time that degrades them. Those AWP's weren't even in the fridge. If the fridge makes them last even better I'm in on stocking up.

 

[Rossum]

What I take from that is batteries can potentially last a long time. To some extent it's use not time that degrades them.

My observation is also that use degrades them much more than age. That's not to say that there isn't some degradation with age alone; I believe there is, but that it is relatively minor, particularly if care is taken regarding storage conditions. There's also a possibility that degradation with age isn't linear; i.e. that it worsens after some number of years. I am keeping several pairs of older, "unused" cells around instead of putting them into service in an attempt to find out if that becomes a factor after some number of years.

And if you put it on YouTube I would know it was true.

I'm not much into making videos. But if I were, I would put them on a less censorious platform than YouTube.

 

[UncLeJunkLe]

It might be even worse than that UncleJunkle. As of May 1st, all manufacturing and exporting of vape related devices may end coming from China.

China Set to Prohibit Sales of Flavored Vapes

It was bound to happen

 

[CMD-Ky]

Yup. The inconsistency of opinions regarding storage temperature is why I decided to do my own testing. Some people say there's no benefit to cooler temps, others do. Who are you gonna believe?

Well, I think that I am going to believe you based upon your history.

On another note, I bought an iPhone the other day, my first. Of course it came without a plug in charger. I ask the guy what was the slowest charger he had and he looked at me askance. He told me Apple recommended this super high rate charger. I declined the offer and wanted to know what else did he have. I took one that charged at about 40% of the 'recommended' charger. Sometimes the tortoise beats the hare.

 

[UncLeJunkLe]

I'm not much into making videos. But if I were, I would put them on a less censorious platform than YouTube.

Although this is OT...but putting non-political videos anywhere else but on youtube is suicide. YT is the king of videos, like it or not. No one but political content creators are affected by youtube policies surrounding political content. For instance, try looking for useful (or any) how-to videos on any other platform and you'll run back to youtube. And the uploaders know this so they upload to (drumroll, please)....youtube.

 

[Rossum]

No one but political content creators are affected by youtube policies surrounding political content.

I disagree. YouTube censors plenty of things that are not at all political. In any case, it's a matter of principle for me.

 

[BillW50]

The big no-no is charging them while they are cold. That is indeed dangerous.

I also heard draining them at those temperatures can also cause them to become unstable.

It has been speculated that there is a sweet-spot for charge rate. Not too fast, not too slow. But I absolutely do not buy "the quicker you can charge the better". Fast charging generates heat, and heat is bad.

Of course, that is why I added "(up to a point)" above. The Samsung INR18650-25R datasheet (from 2013) for example, says you can charge them at 4A max. But did you ever try it? I have. Using one of my RC chargers, I can set the max current say at 4A and the cell won't take 4A at 4.20v. It will be something less, more like 2.5A. Same deal with my variable power supplies. Dial in 4.2v @ 4A and they will only still take only 2.5A tops. I'm guessing it's the internal resistance that limits the cell from taking a charge too fast.

You have to feed it something higher than 4.2v to get them to charge faster (highly not recommended). And even at 2.5A, the cell isn't even getting warm. But why should it? That is only charging them at 1C anyway. And charging at 1C always has been the sweet spot for charging for as long as I can remember. Not only for lithium, but for NiCad and Ni-MH too.

Yup. The inconsistency of opinions regarding storage temperature is why I decided to do my own testing. Some people say there's no benefit to cooler temps, others do. Who are you gonna believe?

That's a tall order. Since you have no idea what the secret additives that were added, you are just going to get different results from different batches from each manufacture. They can and have changed the additives from batch to batch. So some you won't notice any harm stored at room temperatures while some will show signs of degrading.

If one were truly preparing for vapocalypse and assumed the supply of batteries were going to be nonexistent, I'd highly recommend those LiFePo4 cells. They would work fine in mechs (you have to build lower resistance coils) or using them in DNA200, 250, or 250C mods. As those DNA mods can be configured to run LiFePo4 cells. As they are highly stable in a huge temperature range, highly forgiving against abuse (almost impossible to get them to explode), and will last at least 10 times longer.

 

[UncLeJunkLe]

I disagree. YouTube censors plenty of things that are not at all political. In any case, it's a matter of principle for me.

When something goes wrong in the home and I need to either fix it myself or pay a plumber $1K, principles be damned, I'm going to youtube. I fixed my furnace late this fall and saved almost $700 all tolled. I didn't have $1K, but I did have $3XX...and time. Unfortunately, I didn't have the knowledge...but I did have youtube . I don't have the luxury to decide to shell out $1K just because I don't ideologically or politically see eye to eye with Google. That doesn't make me any less principled, but it does make for a sad world.

 

[BillW50]

Although this is OT...but putting non-political videos anywhere else but on youtube is suicide. YT is the king of videos, like it or not. No one but political content creators are affected by youtube policies surrounding political content. For instance, try looking for useful (or any) how-to videos on any other platform and you'll run back to youtube. And the uploaders know this so they upload to (drumroll, please)....youtube.

Back OT, even some vaping videos have been pulled from YT. And I fully expect only FDA authorized products will be allowed in the near future.

 

[UncLeJunkLe]

Back OT, even some vaping videos have been pulled from YT.

Well sure, vaping is a political topic in the USA and other countries.

 

[CMD-Ky]

Well sure, vaping is a political topic in the USA and other countries.

And here, all this time, I thought that vaping was a public health and children's epidemic of death topic, silly me.

 

[CMD-Ky]

With the youtube, all things become possible (except free expression). I would like to avoid all things google but it is not possible in the internet world. Some sites won't work if you "ad block" google. It is quite an avaricious organization.

When something goes wrong in the home and I need to either fix it myself or pay a plumber $1K, principles be damned, I'm going to youtube. I fixed my furnace late this fall and saved almost $700 all tolled. I didn't have $1K, but I did have $3XX...and time. Unfortunately, I didn't have the knowledge...but I did have youtube . I don't have the luxury to decide to shell out $1K just because I don't ideologically or politically see eye to eye with Google. That doesn't make me any less principled, but it does make for a sad world.

 

[UncLeJunkLe]

With the youtube, all things become possible (except free expression). I would like to avoid all things google but it is not possible in the internet world. Some sites won't work if you "ad block" google. It is quite an avaricious organization.

I tried using DuckDuckGo for about 4 months and I had to just stop. What a waste of time that was. I use Yandex a lot these days, especially for image searches, but I still use Google. I'm not fully Yandex'd yet, but I like it a lot.

 

[Rossum]

The Samsung INR18650-25R datasheet (from 2013) for example, says you can charge them at 4A max. But did you ever try it?

No. Unless I'm in a hurry, I charge my 18650s at 500 mA. I generally get no perceptible temperature rise at that rate. On those rare occasions when I'm in a hurry and charge at 1 A, I do notice a small temperature increase.

And even at 2.5A, the cell isn't even getting warm.

Perhaps my fingers are more sensitive to temperature differences than yours?

So some you won't notice any harm stored at room temperatures while some will show signs of degrading.

I suppose then it's a good thing I keep adding new, different cells to the test.
Currently it's VTC5As (3 years) and P26As (2 years). This year, I'm adding P28As. However, I see no way to account for variations in the recipe of the secret sauce within a type of cell.

Bottom line: I don't know of anyone else who has ever bothered to do this kind of testing over a period of years.

 

[CMD-Ky]

Bottom line: I don't know of anyone else who has ever bothered to do this kind of testing over a period of years.

And I am looking forward to the results.

As far as charging, I am a low and slow guy. I have several batteries in circulation. I don't go from device to charger, I always go low charge, I never go from charger to device.

 

[BillW50]

No. Unless I'm in a hurry, I charge my 18650s at 500 mA. I generally get no perceptible temperature rise at that rate. On those rare occasions when I'm in a hurry and charge at 1 A, I do notice a small temperature increase.

Professor Jeff Dahn is highly involved with lithium cell testing and does it for a living. And he has clearly shown, each cell has a fixed charge hour clock and once it is reach, due to the lack of cell capacity quickly degrades and becomes useless. So charging them at 500mA burns up that clock up twice as fast as 1A does.

Perhaps my fingers are more sensitive to temperature differences than yours?

I use IR temperature probes and 2.5A only increases the cell temp by 15°F (feels only slightly lukewarm). And if you plot the graphs, it is still a gain in longevity against the charge clock vs. lower charge currents.

I suppose then it's a good thing I keep adding new, different cells to the test.
Currently it's VTC5As (3 years) and P26As (2 years). This year, I'm adding P28As. However, I see no way to account for variations in the recipe of the secret sauce within a type of cell.

That's the problem. Sure you can test each batch from each manufacture, but change the batch and/or manufacture then all bets are off.

Bottom line: I don't know of anyone else who has ever bothered to do this kind of testing over a period of years.

Well Professor Jeff Dahn and others have been doing this for years. Without the big bucks of EV sales, none of this research would be possible. And I don't believe any one of us could do a better job then what has already been done. Well not at least with a few millions of dollars worth of lab equipment. And having a SEM (scanning electron microscope) would be a huge plus.

 

[Rossum]

Professor Jeff Dahn is highly involved with lithium cell testing and does it for a living. And he has clearly shown, each cell has a fixed charge hour clock and once it is reach, due to the lack of cell capacity quickly degrades and becomes useless. So charging them at 500mA burns up that clock up twice as fast as 1A does.

Since he's a professor, I would imagine he's published a paper with those findings. Got a link?

Well Professor Jeff Dahn and others have been doing this for years.

Really? They've put cells in storage for years at different temperatures and then tested 'em? Again, got a link?

 

[CMD-Ky]

Interesting discussion, please do not stop. Inquiring minds (without much knowledge, such as mine) want to know.
Battery longevity and the conditions under which it is maximized is an important topic.

 

[gloopdegurp]

I stopped at a new (to me) shop earlier this week and picked up another Arbiter 2 for my stash and will probably visit again next week to add another Arbiter Solo.

Some others there that I'm considering include the Kylin Mini V2, Kylin M Pro, Profile (RDTA I think, it was rather big), and Ammit 25.

They also had some older RTAs including the Lemo and Lemo 2, which are more the point of this post.
I was looking to see some of your thoughts as to whether either of these might be good to add to my stash as well.

I am not really set on any particular style of draw or vapor production for my stash, just hoping I pick some nice solid options.

Thank you for any thoughts!

 

[hittman]

I stopped at a new (to me) shop earlier this week and picked up another Arbiter 2 for my stash and will probably visit again next week to add another Arbiter Solo.

Some others there that I'm considering include the Kylin Mini V2, Kylin M Pro, Profile (RDTA I think, it was rather big), and Ammit 25.

They also had some older RTAs including the Lemo and Lemo 2, which are more the point of this post.
I was looking to see some of your thoughts as to whether either of these might be good to add to my stash as well.

I am not really set on any particular style of draw or vapor production for my stash, just hoping I pick some nice solid options.

Thank you for any thoughts!

The Ammit 25 is an old tank. I’ve got one in storage somewhere.