01 CAt Man Do

Pretty much depends on your personal opinion on whether cost is a motivating factor. Since in my case I know well ahead of time how I generally use my cells, cost was indeed the major motivating factor. I typically use my 18650's in standard single XM-L or XM-L2 LED torches that use only one cell. If I'm using ( for example ) a torch for a helmet light; I only use the torch when needed for either twisty or fast sections...Or if I'm riding road and using a helmet torch the torch is usually only used for moments at a time and only for moments on boost. Either way for most of the rides I do with torches the rides are generally within two hours. If I'm using the torch full time it's mostly being used on the medium mode and I always carry a spare. The battery is rarely ( if ever ) majorly tasked. Not unusual for me to finish a ride just using the one cell. ( *Note; I've tested cells when run on typical medium output and been able to run the torch 3hrs continuously on one cell. ) In order to do big time damage to a unprotected cell ( from a discharge point of view ) you would have to do a very deep discharge and likely do it more than once. Now if you start killing cells than yeah at some point you need to realize that you should be using protected cells. Up to the user to decide whether or not saving that $6-$10 per cell is worth rolling the dice on. If you know what you're doing and know how to safely use unprotected cells you can buy those unprotected cells and whistle while paying the bill...

As for charging I don't see a safety issue as long as you have a charger you know charges to 4.2 volts and is reliable. Now if you say a charger could fail; yes, that could happen. Any electronic circuit can fail, even the ones used on the cells themselves for protecting the cells. Stuff like that happens but really it's rare. That's why it's always recommended not to charge Li-ion cells in an environment that has flammable elements nearby. When I charge mine I'm always there to monitor just in case something bad were to happen. All of this said; "If you're a novice and haven't used 18650 cells much than I highly recommend buying protected cells and using them for a couple years". Very important to get an idea of how the cells you buy are going to be used before you decide to buy unprotected cells.

reppans

Get quality Li-ions and charger from a reputable vender, these things can turn into toxic road flares if mistreated. Stay away from anything named 'xxxx-fire' batteries, AKA 'startfire' cells.

HKJ of the flashlight forums is the ultimate battery/charger tester and guru:

18650 Comparator

lygte-info.dk

BBassett

There is a little difference between charging a single cell and a 17 lb. triangle pack that holds over 30Ah. This isn't the place to save money even if you are only using a single cell in some high-speed hand torch. If you are using Li-ion cells in an ebike battery pack use a Cycle Satiator made by Grin Tech. (The Satiator, Programmable Battery Charger) to charge them. My Satiator is programmed to quick charge at high amps until the pack approaches 70% then drop to 2 amp and slow charge as it tops off the individual cells to 80%. I don't discharge past 20% in the hopes of getting significantly more charge cycles out of each battery. When a massive ride is expected, the press of a button and the unit will quick charge the pack to 100%... quick is a relative term. Before everyone starts in... yes it is heavy, yes it is expensive, but also 100% water/dust and shock proof. The MJ1 cells Are only slightly better than the last round but give me over 2Ah of additional power capacity in triangle packs of the same weight. 28.2Ah vs. 30.6Ah and I will take every bit I can get.

01 CAt Man Do

I have to admit I'm a little confused by the entirety of your post. Not sure what point you are trying to make. That said I have to disagree about the first part. A single cell is about $6 and a 30Ah Li-ion e-bike battery is usually in the $900 range. With this fact as perspective I can duly understand someone wanting the best charger to charge an e-bike battery. On the other hand I can understand the person who just buys a couple cheap Chinese cells and then buys a cheap Chinese charger. I say that because when the first good torches were first coming out many people ( including myself ) were using the cheap Chinese batteries ( and chargers ). Eventually the cost of good cells came down and I decided that it was just worth buying better quality cells. Not to mention more safer as well. That said I never had any problems with any of the cheap Ultra- or Trustfire cells that I owned. The only down side was that the cells were likely only in the 2000 mAh range even though the labels would say *2600 mAh. ( *Actually the red XLS Ultrafire 2600 mAh cells I had and the Black/red/fire Trustfires..2600 mAh I had were both rated fairly well over on CPF during the years I was using them ) I did have one cheap charger go up on me but also have three others that work fine and have worked fine for many years.

Like I said before though, no need to buy cheap low capacity cells now as the good stuff is now very affordable. Turns out I will be getting a new charger for my 18650's but only because I want a charger that will identify bad cells and give a capacity read-out. I've found a couple that will do that but I'm waiting to see if I can get a better price. Sometimes it pays to shop around. ( although this time probably not ) Right now just looking for a USA seller.

Interestingly that during my discourse on the use of unprotected cells, I just so happened to have an incident with one of my unprotected cells. Sometimes stuff happens that you don't see coming. Turned out the torch I was carrying inside my work bag somehow found a way to turn itself on. That torch had a fully charged unprotected cell in it. I figure now that somehow the push button on/off switch must of been activated by contact with some of the other junk I carry in the small bag. Since I don't use the torch at work much I haven't had to take it out for over a couple weeks. I only took it out today because I thought I might need it for a bike ride. That's when I discovered that the battery was stone cold Dead. Dead as in a door nail. Completely drained, will not recharge. Lesson learned; It's okay to use unprotected batteries. Just make sure that if used in a torch, that the torch is both set on the lowest mode ( mine was ) and that you have protection ( box, cap..etc ) for the power button "IF" you store the thing inside something that might accidentally hit the power button and turn the damn thing on. Of course if I had used a protected cell the worse that would of happened would have been that the battery had drained to cut-off...in which case the battery is still good and rechargeable. Looks like Mr. work torch gets a protected cell. At least until I find a better way to store the torch..which...is still an issue.

KD5NRH

I charge in a dirt-floored, rock-walled garage. Gas cans and such are 15-20 feet away from the charger, and ventilation is good enough to prevent fume buildup from those. Unless it flares high/hot enough to set the wood ceiling on fire, the worst that could happen is the pack for my Trek's headlight (which I usually charge on the bike because I've forgotten it a couple times when I took it off to charge) might trash the frame.

noglider 

@KD5NRH, it sounds like you handle the risk reasonably. It is here on BF that I learned the risks of cheap lithium-X batteries, so I'm not an expert. But some people here are.

BBassett

As always, you get what you pay for. Buy cheap crap and you have to be willing to pay the consequences, however large or small, from a cell that is depleted at an inopportune time, to a raging fire that hopefully will be covered by an insurance plan.

KD5NRH

Really? Because I've got 10 Ultrafires I'll sell you for $150. That should make them better, right?

vol

I unscrew the flashlight if I carry it in a bag, just loosen it enough so it would not be able to be turned on, originally because otherwise it leaks the charge, but now I see another reason to do so from your experience.

Layman question: So is a completely drained (or very undercharged) battery more dangerous than an over-charged one? Should I regularly partically charge the batteries not in use, say every month or so?

A0X0M0X0A

I just bought these from amazon, I like them a lot and the work great.

I use them in my Cree flash lights and some green lasers.
Search AMAZON for

2 Efest Purple IMR 18650 2500 Mah 35a 3.7v Rechargeable Flat Top Batteries

01 CAt Man Do

Yes, this is true. Just keep in mind that a chance that a cheap Li-ion cell is going to go up in flames is rare but yes it can happen. If the cell gets damaged somehow It could cause a soft short that could eventually cause the cell to vent or to ( worse case scenario ) go up in flames. Just remember that this can happen to any Li-ion cell, not just the cheap ones. That is why it is best to charge your cells in a safe place and only when being monitored. When it comes to cheap 18650's the most likely thing to happen is you just get a cell that has a lousy storage capacity. If I can buy a cell, spend $3 more on a good brand name battery and get a real 3200 mAh capacity vs. 1800 mAh, I'm gonna do that. Like I keep saying, no good reason to buy so called xxxx-fire cells anymore unless you just don't care about actual capacity ( which is the dominant issue ).

@Vol; In answer to your questions about batteries completely drained or at very low voltage; No, I don't think there is a danger. An unprotected Li-ion cell that has completely drained just won't charge. Low voltage cells will still charge in most cases but might not retain it's original capacity. Once the cell loses all voltage though the battery forgets which end is positive / negative and doesn't charge. I read somewhere once that there are special chargers that can sometimes revive dead cells. Don't know much about that though. FWIW, I took the drained/dead cell I had and tried to charge it. It sat in the charger at least 3-4 hours..never got warm or anything. I took it out and measured the voltage on the battery and it came up zip. Just to be sure my meter was working I measured another cell and the meter was working fine.

I have a new charger on order and should arrive by the end of the week. I can't wait to measure the capacity on some of my old Ultra-fire cells that must be almost 10 yrs old. About the storage or stand by charge issue; Always best to keep the cell on less than a full charge if not being used regularly. That said I rarely do this myself. Once the weather becomes nice enough and I start to use my torches ( or bike battery packs ) more and I generally like to keep the packs or cells charged and ready to go. Then once I use them, I'll not charge them again until I think a ride is possible the next day. Regardless of what you do with your packs ( and or loose cells ) your batteries are going to age and lose capacity. You can slow the process but you can't stop it. Of course this doesn't mean they aren't usable just because they are older. I don't think about replacing mine unless I really start to notice a significant loss in run time. With Li-ion cells being cheaper now, I can do this every three or so years now and not worry. Older cells I keep for "around the house" use.

Damn, why didn't I think of that... Thanks for the advice!

01 CAt Man Do

UPDATE FROM MY LAST COUPLE POSTS!

Lucky me! I just found out I didn't kill my unprotected battery. It seems my voltage meter had some really old batteries in it. I just found this out by trying to measure my good cells and nothing read a voltage. I opened the battery door on the meter and yep, one battery was so old it was leaking and corroded. I put new batteries in and damn!...measured my so-called dead cell and it has a 4 volt charge on it. It's possible it might not get up to 4.2 but when the new charger arrives I'll put a really slow low charge on it and see if I can milk it back up to over 4.1. The real question now is, "Was it completely drained? Don't know since I did try to charge it. Likely it was near dead

Oh, and Vol...If I do unscrew a torch and store it my bag I have to mark it in some way or likely I might forget about it being unscrewed...and then cuss and wonder why the damn thing doesn't work...lol.

vol

Thanks for the comments, CAt Man Do.

It will become a habit

01 CAt Man Do

Just got my LG MJ1's ( 3500 mAh ) in today. These look like nice cells. They are undoubtedly heavier than any other brand cell I own including my Panasonic NCR18650A's. Can't wait to test their actual capacity.

BBassett

I hope you are as happy with your's as I am with mine. Happy Riding.

noglider 

Do you folks really measure your cells' capacities? Man, I thought I'm the most obsessive one. How do you test them?

01 CAt Man Do

Personally I've never been able to do that. You need a charger or other set up that allows for that. I always wanted one but up until recently I never saw something that would do a discharge / mAh read-out unless it was a hobby charger. There are some nice compact chargers out now that will let you adjust the charge level, charge different types of batteries, do discharge tests...etc. I should have mine by the end of the week. I wanted the Opus C3100 but settled for the AccuPower IQ338. Just didn't feel like waiting for shipping from China.

seeker333

There are a few li-ion type chargers that totalize milliamps as you are charging cell. If you deplete cell fully before charging, then you will basically measure it's capacity. I link the charger plus a good battery supplier here.

01 CAt Man Do

Follow up with the cell that I thought I killed;

I'm figuring now that perhaps I was wrong when I thought I had accidentally killed my unprotected Panasonic.
I just ran a discharge / charge test on the cell I thought I killed. Discharge ( @300ma ) measured 3155 mAh. The Charge ( @ 500ma ) took 2951 mAh. The cell is about two years old and I figure it's still in good working order.
I'll test the LG's once I've used them a couple times. Right now I'm doing a discharge test on the old red Ultra-Fire XLS I still have. Those must be 7-8 years old. I figure if they provide 2000 mAh or more they are still usable. Of course the U-fires were likely only rated for about 5A so they'll not see much use.

01 CAt Man Do

I finished measuring the capacity of the old 2600 mAh Ultra-fires I have. The cell accepted a 1700 mAh charge ( @ a 700ma charge rate ). Forgot to get the discharge rate. Anyway, not as good as I had hoped for but considering they are likely 8 years old or older, not too shabby. I was discharging at 500ma. I do know the discharge lasted more than three hours. Once again, not too shabby. If you had a torch discharging at that same rate, the output for a torch ( with Cree XM-L2 emitter ) would provide about 240-250 lumen. That's a decent amount of light and enough run time to get you out of most situations if your main lamps fail. Of course with a better battery you'd do even better.

Right now the only thing keeping me from doing Mt. bike rides with just torches is that torch beam patterns are generally more narrow than typical multi emitter type bike lamps. I like wider beam patterns when riding in the woods. Of course with torches you can't run the higher output modes very long either or else the emitter will over-heat as well. All things considered, if I only had torches I could still Mt. bike at night. The difference being I would have to run less output and have a less usable beam pattern. Doable but not preferable.

Fat Freddy

[QUOTE=vja4Him;18898805]I just purchcased the Magnum Innovation 860 Lumens USB Bike Light. Should arrive within a few days .....

Question: Which 18650 batteries would you recommend ? I will be cycling many hours at night, so I need extra batteries fully charged for every ride.

I have always had great success with the Ultrafire TR 18650, 4500mah.

01 CAt Man Do

[quote=Fat Freddy;19622457]You might want to check out on youtube. Then you might want to read this link that talks about the Ultrafire 5000mAh battery. The UF 5000 mAh cell only tested out to just over 1000 mAh when discharged @ 1A. The key to knowing what are fake cells is knowing what is actually possible to achieve with current technology. 4.5 to 5Ah listed capacity on an 18650 cell is not possible at this time. Once you know that you know not to buy anything that claims that much capacity in an 18650 cell.

If you want good batteries you have to buy good batteries. To buy good batteries you have to know something about batteries and who makes / sells good batteries.

01 CAt Man Do

I just did my first cell capacity test on the 3500 mAh ( listed ) LG-MJ1's I bought from Orbtronic. After discharge the cell took a 3351 mAh charge ( @ 500ma charging rate ). This is pretty much what I expected considering that no cell actually gets what is offically listed. I'm thinking that after using a couple more times I might actually get a slightly higher rating...maybe closer to 3400 mAh. ( test done on an AccuPower IQ338 charger/tester ).

I'm satisfied I've got some great new batteries. In the future I'll buy more of these unless of course someone comes out with a "real" 4000 mAh 18650 cell. Oh and BTW, no problem with fit in any of the torches I own.

BBassett

I'm glad they work for ya. No, I don't check each cell with the cheapest multimeter that can be found at K-Mart like some suggest. I study the data that is released by manufacturers and independent testers that have proper equipment that can test true fade and bounce back and then invest my money. As I have pointed out a couple times its different when you don't just use a single cell at a time. Congrats.

Brittney

Most of my 18650s have come from old laptop batteries that I pulled from the battery recycling bin at work. Breaking one open yields a bunch of 18650s, which I assume come from a relatively reputable source (last ones were Sony). There's normally one or two cells with noticeably lower capacity that results in the laptop battery giving poor performance. I use them for vaping and torches, carrying a bunch of charged ones is easier than carrying a chunky charger for a week or so on holidays