I just got 21700's. I have Efest and Pila chargers. Either ones, the bar is 100% extended and then even must pop in place. I was concerned if this could cause chargers to malfunction? The box for either says 650 series is largest and no mention of 700 although these are about 5 years old. So maybe 21700 just was not out then. I was just concerned if the "maximum" length stuffed in there could cause a catastrophic malfunction? I know LI-Ion is nothing to play with which is why I ask. If I do need a new charger what do you folks recommend(top of the line)? Thank you
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21700 safe in charger?
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Rooster Cogburn
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I don’t think it’s exceptionally dangerous but over time it may cause problems. I had that problem with my old charger which was a pain being so tight and ripped a few battery wraps in the process.
For a new charger the Miboxer C4-12 is an excellent choice. I love mine and it has plenty of room both length wise and between cells. It makes it very easy to get your fingers between cells to remove or insert the cells in their slot. It also has the ability to charge up to 3 amps across all 4 bays which comes in handy if in a hurry with the biggest batteries. It monitors cell temperature and can automatically pick a charge current or you can set your desired charge rate anywhere from .2-3 amps giving you the ability to safely charge any size cells you have including NiMH or Liion. It’s an excellent charger and keeps your cells cool while charging ensuring a safe and fast charge while treating your batteries with care to get a long life from your cells.
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Here is a list of chargers with slot size and other information
http://lygte-info.dk/info/roundCellChargerIndex UK.html
By the way the miboxer c4-12 is 33mm wide X 73mm long slot. Which is plenty for the 21700, like I said I have one and it’s roomy with 21700’s
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I got mine because my LiitoKala Lii-500 charger was so tight with my 21700’s. The spring on that one was super strong also which ripped a few wraps. The Miboxer is nice and roomy, easy to get the cells in and out. By the way that link I put in my other post is handy for charger reviews. Might be worth a bookmark for future reference.
Battery Mooch lists the Efest Luc 4 as 21700 compatable. But as I stated "a tight fit". As I said watch your battery wraps. Replace as needed. A short term usage as others are designed to fit better. Again Golisi 4 bay. An excellent product at a good price.
I decided to cancel Amazon. I got a Folomov A4 locally. It said '700 is a tight fit but mine fit fine. That chart says 70mm but I would say more like 71mm. What I liked is it can charge up to 8A! I am not sure if that is begging for an explosion. Or if it will be charged so fast it's over before any damage. Of course I would not do that regularly. I have it on 2A. I have a question for you folks though. My understanding is 1A per 1000MAH. So these batteries are 3,850MAH I can charge at 3A? Or that is unsafe and will not last? I got the thing for $13.50 because I know the guy so I figured why not? It does not tell temp. Although I am not sure how accurate that feature would be anyways. Temp of charger or battery? If battery I doubt that is very accurate since it is not actually measuring the internal plates. 2A gets to like 27C. With laser temp. Just not sure 3A is okay on these? Anyone have data sheet? They are Sangtung. I believe a rewrap of something. It says 26A continuous.
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I sometimes charge my 21700’s at 1.5a and my 18650’s I charge at 1a tops. Are you sure your charger can charge at 8a!!!! That’s unheard of and I think you have been misinformed. My goes up to 3a on all 4 slots and I thought that was one of the highest.
Edit: I’m seeing up to 2a on all 4 slots and 3a on slots 1&4 only on two
Yea the max charge rate on a lion battery is 4a or at least they rate them that way. My charger the whole charger won't charge more than 1.5a yours using 4 slots charges as fast as mine using 2 slots
8A on one slot. Stupid. However this thing is actually very smart. It starts depleted cell at 250ma. then 500ma. Then it determines best rate for each battery. Then once again slowly trickles down to 250ma as it tops off. Takes longer than overriding it to 2A but cells probably last much longer this way. I never knew this charger but does not seem bad. Has all the usual protection and then some like thermal protection. I figure it was good for what I paid.
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Yea I’ve heard good things about Folomov chargers and for the price you paid it’s basically a must buy. If for nothing else, then a backup, it’s nice to have equipment to fall back on in case of emergencies.
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Enlighten me on what "actually depends". Because I didn't hear anything in the video that says over 2a (on a regular basis) is ok for battery life.
From what I have heard from various sources is to charge at 2a seldomly or preferably not at all. I may be right I may be wrong but I personally never charge at over 1a. Even if I have to do without a vape for a bit. I mostly do .05 so I try to make shure I have extras on hand.
Well what you say is very interesting. this is the newest technology of "smart" charger. It will very rarely select to charge at 2A. You must over ride it. As if it were saying to me, no, no you idiot. Now if I put in 5500MAH 5A 26650 it does go right to 2amps but not 3! This thing is obviously smarter than my own good.
Well this thing is smarter than me I guess. If you put in a cold depleted battery and set it to 2A it immediately sets it back to 250ma. even at 3.7V I put it to 2A and it restarted at 1A. Not until over 4V will it start at 2A or 3A(if you are really stupid). Therefore I do not know how it can do 8A "quick charge" in one slot. I would not try that stunt anyways. Yes, it takes longer to charge than some older ones that you can set right to 2A. However it is saving the batteries. Moreover it is saving my ass. It charges exactly to 4.20V. Other chargers I have charge to 4.22-4.223V, It also monitors them thermally and if too hot will ramp down amps or shut off. I think this is a pretty good charger. Only one thing. When brand new the sliders were very stiff. Broken in already. It also is designed so they do not snap back and break! When I remove a battery it travels back slowly. This was worth what I paid. Since Amazon has it for 3 times that much. I gather you guy's do not know anything about it? It has not been reviewed yet. It just came out 3 weeks ago. My guy told me it is the most advanced charger made yet. Chinese company, to be expected but made in Malaysia! The 21700 is a bit tight but I doubt enough to rip the wrappers. Overall even though it takes longer I am pleased with it.
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Here’s a review of that charger and like @Vape Fan said, it came out in 2017. https://lygte-info.dk/review/Review Charger Folomov A4 UK.html
That link I provided earlier in this thread that lists all the chargers and some specs. If you click on the name of the charger you will see the full review with curve charts and his thoughts on the charger. Best charger review info I’ve seen, very comprehensive.
Also that charger is not the “most advanced charger made yet”. Just for an example this charger came out recently and it’s quite a bit more advanced then your A4. https://lygte-info.dk/review/Review Charger Efan Lux S4 LCD charger UK.html
Your charger is nice and I’m not trying to give you grief. It’s just some of the information in your post is suspect so I was trying to show you what’s out there.
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Check out that link and base your choice from the reviews. My pick would be the Miboxer C4-12 or the Miboxer C8 if you want 8 slots. I love my charger, every other charger I’ve used gets the batteries pretty warm while charging but when I charge with the Miboxer the cells hardly get warm at all. It monitors the temperature while charging and will lower the charge rate if they get too hot. They do this if you just put the cell in and let the charger decide the charge rate (based on internal resistance) or if you pick a charge rate. Even charging four 21700’s at 2 amps, they stay surprisingly cool. Best charger in my opinion and it’s only around $30-40 if memory serves me.
With this link at the top it lets you choose the type of charger you want (li-ion only, nimh only, universal, analyzer) to narrow down the list if you want a particular type. Otherwise just look at them all and at the right he gives smiley face ratings. Find one he likes and click on the name to see the full review. Decide which charger works best for you based on this.
http://lygte-info.dk/info/roundCellChargerIndex UK.html
Thank you. The Folmov is either busted or sucks. At 2a battery got pretty warm in it but did not in LUC. Although LUC charges to 4.22V. Since you folks concur to charge at 1A. Right now I am using my old Xtar VP4. The slots are 73mm. It had served me well for a long time. I se nothing wrong with it for now? I used the Folmoc cord set with it because that part at least is much nicer. It is the proper rating for the Xtar. Although it seemed to charge faster with it. Perhaps my imagination. It takes about 1 minute per .10 amp and about 5 minutes for the last .10 amp. so If I put in a battery depleted to 3.2 going to 4.20 takes only it should take 10 hours but that does not seem right. Since it seems to charge in about 3-1/2 hours. Big difference unless I did the math wrong plus I did not actually time it. With plenty of batteries of all sizes on hand I might as well treat them right and charge at 1A. That charger was fine back in the day so I imagine it is still fine for now? I will certainly be getting a new one after I read the reviews. Although if I am only going to charge t 1A do I really need to even replace the Xtar?
Efan is just a "good" charger. It has some issues. Not really "smarter" just has probes. Folomov is junk after all. I just reordered Miboxer. The weird thing about my LUC is one slot is much longer than the others. That is very strange unless wire is just stretched out. This is taken care of though. Thanks folks.
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I was gonna say just stick with the Xtar. Even though it’s old it’s still a really solid charger. Anyway that point is now moot, I hope you like your new charger and the Xtar will be a nice backup. Always gotta have backups for your vape gear so when something breaks you don’t run out and make a hasty purchase.
The sweet spot is what actually depends. I usually charge the Samsung 20S at only .75A, vs 1.5A for the Samsung 30T.
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Not to hijack the thread, but I'm getting batteries for dual parallel unregulated. I'm not lower than about .12Ω and am thinking VTC6A [x2=40A+] would be a good choice for the [added 2000mAH] run time. Any thoughts?
Yes but nobody has them in stock AFAIK, and the same applies to the Samsung 24S and 25S. So unless you can find them, your best bet would be the Vapcell green 25A 2600mAh, which is a rewrap of the Molicel P26A 35A 2600mAh that has a CDR of 25A.
40A is like the biggest batteries with any decent MAH so yeah those are good I think. If you need 60A and I am not sure if you do you are only getting like 1000mah batteries then. Mech can draw huge power. Hopefully someone that knows better tells you but those are very good batteries. I am all set so go ahead and help him. Wish I could charge at 2A but better to save batteries and I have a bunch so not like I am waiting anyways.
I use The Nitecore Q2 for large batteries..... Works perfectly and it's cheap and cool looking....
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There are no 18650 batteries with a CDR above 30A. The Samsung 30T does have a CDR of 35A, but it's a 21700 battery, and, of all the 18650 batteries that have a CDR of 30A, right now the Samsung 20S performs best (for both regulated and mech).
I use a Nitecore NEW i4 and I keep my older Nitecore D4 (2016 version) for backup. The NEW i4 has a feature called "priority charging" that, when enabled, allows you to select a bay that will be charged first so it puts the other bays on hold until the selected one has finished charging or until you select a different one (or you disable priority charging), and, immediately as soon as only a single bay is left charging, that one automatically switches to 1.5A if it contains a high capacity cell.I use The Nitecore Q2 for large batteries..... Works perfectly and it's cheap and cool looking....
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I don't worry about priority..... I put the battery in and the first one that turns green.....Bam hit that bitch........
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Manny, I see you are charging at 2 amps? I once had a thread about charging amps a long time ago. The consensus was 1A per 1000MAH. In this thread no one agrees with that. Odd. Or has more information come to light recently? I have charged batteries 3000MAH and above over 500 times at 2A and still work fine? Unless they have reduced capacity and I have not realized it? One thing I kind of doubt at least is that 2A will cause venting on high capacity batteries?
Nope... My chargers are all set at .68 amps........
I have Sony VTC5 that are 3 years old and hold a perfect charge.....
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It Charges (6) at .68 and has the capability of charging (2) only at 2.0 amps......
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2 amps it's ok.... But instead of 400-500 recharge cycles on the cells you get 250
It just fries the long life of the battery...
Like a cell phone..... Let it drop to 10% and fully charge it every night and you get years of balanced battery life...... Charge it all the time or at 70% charge and all you are doing is killing the Li-ion battery life....
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As long as it is not enough to make it vent I do not care about $8 battery. I do care about $1,200 Phablet phone. Places can replace batteries but never goes back together right plus leaves marks on case. Anyways as I said perhaps I am lucky. I have recharged big batteries at 2A over 500 times and still going strong. No loss in time. I honestly think 4200+MAH batteries can handle it. In fact in the data sheets it often says 4A quick charge is acceptable. So my feeling is yes, 2A is not good but shall suffice. Just like sugar is not good but most people do not get diabetes. It depends on your charger vastly as well. how "smart" it is. see mine start out at 250ma ramp up slowly to 2000ma and taper back to 50ma. All good chargers probably do. it is not starting a depleted cell at 2A. That would be very bad. It is not the greatest but should not cause imminent failure either. The issue is batteries are $8 and in my case have had great service life at 2A. Chargers are $30+ and fill up our landfills. On that note many people throw away batteries. It is just a fact as sad as it is. Do you really want to kill your hardworking trash person? I think maybe I am just lucky although these are big batteries. I would not do 1A per 1000mah on a 200mah battery but on 4000+ I "think" it is okay. Manny, you must run out of all 12 before they are charged LOL.
I try to keep the (15) I use the most with fresh batteries..... Plus the ones for back ups... Batteries are a must have.....
I also use flashlights that hold (8) 18650....... So I really use batteries....
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I dig flashlights too. We have a lot in common Manny. That is like 5000 Lumen light? I keep fresh batteries at float charge too. I regularly use one at a time in Stabwood Mods of course. Rotate 12 charging, plenty. Seeing as I have gotten over 500 charges at 2A maybe lucky but why not then? I keep 2 packs of 100 18650's and 4 packs of 50 CR123A for flashlights plus many rechargeable. We are certainly ones that should recycle and I always do.
You like LUC? I see unwrapped batteries in there!
You like LUC? I see unwrapped batteries in there!
Are you trying to tell me you own 101 batteries and you're still not a high wattage vaper?I don't worry about priority..... I put the battery in and the first one that turns green.....Bam hit that bitch........
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We are talking about the "sweet spot" that is the "ideal tradeoff" between slower battery aging and faster charging. Generally speaking, the sacrifices you're gonna make in terms of faster battery aging start to grow fairly big once you start going up the ladder from 1A, up to 2A charging. Whereas the further you go down, from 1A down to .5A charging, the smaller these differences will become so, below .5A charging, that's where differences fade into the distant landscape. So for a larger capacity battery the actual sweet spot might be typically somewhere halfway in between 1A and 2A, whereas for a lower capacity one it might be (again, typically) somewhere halfway in between .5A and 1A, and, some batteries it might be much closer to 1A. It depends on the characteristics of the battery itself. (The battery capacity is mostly just a raw indicator that can be used for this purpose if you haven't got a more accurate way to tell, but battery temperature is another useful indicator that tends to be more/highly representative.) Also it depends on how much heat the charger generates and transfers onto the battery, and on how much time and patience you have when you charge batteries or how much you dislike faster battery aging.
As long as it doesn't cause anything to start to overheat, it should still be reasonably safe. But it comes at a significant price called faster battery aging, and that can be VERY significant if you do that all the time, especially with the lower capacity type batteries such as the Samsung 20S, for example.
Yes, for the 4200+mAh ones, 2A charging tends to be very acceptable/reasonable. But that's assuming the charger doesn't heat up too much because if it does, it heats up the batteries significantly thereby causing the batteries to still age much faster than what most "pragmatist" (for lack of a better word...) people would consider fairly normal battery aging rates.
Man...... It's tough keeping up with batteries when you vape (15) mods at a time and keeping all in rotation.......... and some are (3) batteries some are (4) batteries are some 18650 some 26650 some 21700 some 20700Are you trying to tell me you own 101 batteries and you're still not a high wattage vaper?
Man what a nightmare......
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