An Idiot's Guide to 18650's - Under Construction

It would almost appear the CPF opinion that the 18650’s in your bike light is more dangerous than riding. Better invest in a blast containment chamber for the battery pack rather than a helmet.

That’d be hard, but you can buy a car powered by Li-Ion batteries - the Tesla Roadster has ~7000 Panasonic 18650 cells!

Hello again, thanks all, and thanks sintro, Gimpy and torchythebatteryboy for the replies…

I don’t think the batteries I ordered have protection, I ordered them to use with TrustFire T1 (uses 2 x 18650 in serial connection)

I checked all the ebay and other websites they all sell flashlights that uses multiple li-ion with cheap batteries without protection (they even claim 4000 mAH) in bundle with real cheap chargers. If it is dangerous how and why they sell these?

Because they’re not.

Cheap doesn't necessarily mean that they are bad. My beef with Ultrafires is that they are so inconsistent in quality. You might have a decent charger and cells in your hand, but without the right testing equipment you will never know. Not everybody has the equipment, time, money and endurance that HKJ and old4570 have, to really test out the pro and cons of cells and chargers. If you want to continue to use those cells and charger, I would at least invest in a cheap but good DMM so that you can check voltages to see if cells are overcharged or too empty to use them safely. In a dual set-up like 2X18650 the same charge level is also important. My biggest pet peeve with unprotected LiIon cells is that something like leaving the light on and forgetting to turn it off can already change the chemistry to the point where it would be unsafe/ not recommended to recharge the cells at high amps. That is something that non-technical people still have a hard time to wrap their mind around ("When it's empty, I simply recharge it. Where is the problem?")... and when I do try to explain the effect on the chemical level, they look all funny at me.

The best overview of the potential risks that I found so far is at Battery University. But like other people already mentioned, these articles already are more for tech-savvy people or "beginners that are willing to learn". I don't like the thread title in particular, because "Idiots", or people that won't bother to invest some time in reading about battery safety simply shouldn't use LiIon cells in the first place. They need electronics that do all the thinking for them, like in cell phones and notebooks.

My gawd man, just give it up !

You’re like a dog with a bone. You’ve made your point eight times, now please move on and let the OP do what he wants to do.

So when are you planning to get around to criticizing the CPF + wannabe crowd for repeating ad infinitum blatant ignorance on this topic well before I was even around? Perhaps one reason why I might need to repeat a point is that apparently some have poor memory, such as when I said OP can write what he feels is right. I only hope others such as yourself can find the basic courtesy to extend the same to me.

I gave one of my friends a 14500 for a UfH2. I told him when it goes flat tell me and I will charge it for him or he will need to buy a charger. He said he will charge it in his nimh charger. I told him not to and explained why. He looked doubtful so I took the battery back of him and told him to stick to nimh. Even reading a thread like this he would still try it.

Yup, there’s very little in the way of safety information provided by the sellers of this stuff. I don’t know why. Some sellers will mention a few safety precautions, but might not give you everything you need to know. I guess most sellers assume that the people who are buying this stuff actually know what they’re doing, and will take responsibility for it themselves. I suppose, also, that some of them just don’t care.

Agenthex can stick to his conspiracy theory regarding CPF, but here’s what an ACTUAL manufacturer has to say about their product:

In general, it’s considered poor marketing to claim that your product can explode and catch fire if, in fact, it will not. And somehow, I doubt Panasonic was heavily influenced by propaganda on CPF.

Gimpy, I hate to burst your bubble, but the same dire warnings on product safety and misuse can be found on almost any consumer product sold in the U.S. Why? They have lawyers working for them and somewhere, at some time, someone got sued.

Li-ion batteries that we use in lights, like many other chemistries, can be dangerous if misused. Learn about them, respect what they can do, treat them well and life will be good. Agenthex has a point: I ride my bike 5-6,000 miles per year on the road. Believe me when I say I am much more worried about the guy riding 1 foot off my front wheel or the 2 ton car following behind us than I have ever worried about the 18650 battery in my flashlight.

By all means, keep writing and definitely have a section on battery safety, but try to keep it in perspective. You know if you drop a few Mentos in a liter of Diet Coke it will explode.....

I am sure about the danger of all li-ion batteries, if you google you can find news everywhere exploded phones or other devices also 18650s…

I don’t know anything about the electricity or electronics but I am totally agree now after some research, if they are used in serial connection without protection the danger I guess doubles or maybe more.

I want to use this flashlight while cycling so I don’t have time or equipments to test them all the time, I just want to use them charge them again and use again, also I see myself really stupid (or idiot like the title of the topic:) so I really do not want a bomb on my bicycle near my face.

Can anyone please recommend me a normal priced (not very expensive, if possible cheap:) 18650 with a fully working pcb protection to use 2 of them in serial connection?

I found this: Boost - Buy In Coins

What do you think? Are they original?

Most of those sellers are in china. So they don’t really have a risk of getting sued like in the United States. I myself used to look at them, but they just seemed to good to be true, so I did some reading for a few weeks on CPF, and then found out about this site.

The highest capacity 18650 right now is the Panasonic 3400mah cell. You actually have to charge it to 4.2v though.

Basically, those sellers sell fake cells and bad chargers just to make some money! Now, they AREN’T super dangerous. I’m sure they would get alot more scrutiny from everyone if every single person bought those crap ebay cells and chargers, like they do aa alkalines. There would be many more injuries from them, and the lawsuits would follow.

Buyincoins has said to sell fake cells in recent threads, so I myself wouldn’t buy there. Probably the best bang for your buck would be to get some brand of Sanyo 2600mah protected cells. Tenergy sells them, GTL?, Marsfire, and a few other brands do. But the Tenergy’s have good quality control, probably the best out of the under $10 ones (Xtar has good ones too actually, a little bit cheaper too). But GTL and Marsfire are real cheap, like $5 bucks per cell, with Marsfire being the better ones.
*
Can someone give him a link to some genuine Marsfires?*

If someone can’t give a link, I would get [these](http://www.intl-outdoor.com/2-pcs-sanyo-ur18650fm-2600mah-protected-battery-p-516.html(If) I had known about them, and if they were out when I recently bought some cells, I woulda got them):
Here’s a review

What do you think? Are they original?
[/quote]

Erm. The Panasonic’s 3400mAh cell (NCR18650B) has charge termination voltage of 4.2V, just like their 3100mAh NCR18650A cell. Panasonic doesn’t produces 4.35V cells.

For sure! And they got sued because someone started a fire and/or blew themselves up when the manufacturer hadn’t performed due dilligence in informing the end-user.

Amen! My mother put alkalines in the charger the other day, and damn near burned the house down. Had my dad not been sitting right beside the charger, things could’ve been bad. It happened becuase:

  1. mom couldn’t tell the difference between the cells (in fairness, these alkalines kinda looked like our rechargeables)
  2. nobody had impressed upon her the importance of being ABSOLUTELY sure of what you place in the charger
  3. nobody had ever explained the potential consequences of getting it wrong.

Absolutely! The technology is safe, though, in large part becuase you are not an idiot (as opposed to, say, the people tailgating you on the road).

I just want to have a little guide to get people from zero proficiency up to basic competence. I don’t think you, or I, or Agenthex actually have any significant difference of opinion on the safety of the technology. But I doubt any of us would feel comfortable with someone like my mother using this stuff in the house. She could, though, if someone gave her a guide like this. Anyone can look like an idiot if they don’t have the right background information. I’d rather that, then to snatch it away and tell em they can’t use it. My mom DID eventually learn how to use a computer :slight_smile:

Moms are the leading cause of fire in the house together with kids... they should have a warning label. ;-)

LOL! Yeah, pretty much! :slight_smile:

Oh dear oh dear oh dear !

The most dangerous thing about Li-ion !

Is the user , and his or her lack of knowledge . Most battery mishaps can be traced directly back to user error !
And sure , Li-ion , Lipo etc , will flame from time to time , but again , if one were to examine the actual root cause , I would dare to say [ or claim ] user error !
Li-ion is part of our lives , flashlights , power tools and even powering cars , bikes etc .

I dont think the battery can educate itself , so it is up to users , to educate themselves , make themselves safe ! As Li-ion ATM is not 100% safe , but nothing is 100% safe , not even AA batteries , well they might be 99.999% safe but not 100% , and the most important factor with Li-ion , is the human factor !

My brother just gave up on Li-ion , he was simply too lazy to use a MM , or bother to check the batteries from time to time , even though I made him aware of the risks . Now he is back to AA powered lights , as he simply wants to run them down and not monitor the state of the battery . And I think average Joe and Floe probably feel the same way , their really not interested in safe procedures when it comes to batteries [ possibly from decades of exposure to AA batteries and the other sizes ] . There are people out there that never check tire pressure , there oil , or the spark plugs , they simply expect things to work without maintenance .

Sure there are cheap nasty batteries out there , but 99.9% of the time , they need a lot of help before they will flame out , and that help comes from the user !

Bottom Line :

Worry more about people and what they do and dont do , than the battery itself :

My sentiments exactly.

This is a good example of what happens when people take CPF seriously. Tens of thousands of these supposedly “super dangerous” items have been sold, and yet nary a whiff of the wholesale destruction they’re predicted to cause.

In science, we call that a failed hypothesis, the domain of cranks and their adherents.