Which specific models/versions of each? If you started a thread on those already, pointer please — knowing for sure what’s proven to work would be very helpful.
Buzzing Bulb, I think your battery storage methods are just fine. Actually kind of impressive the way you have it all organized. And like Sig Shooter and a couple of others have said… we are surrounded by “potentially” hazardous & dangerous things and situations all the time in our daily lives in & outside our homes.
Look at the things Sig Shooter mentioned. Add to that cell phones, battery packs for cordless tools, even flashlights. Plus don’t forget the Battery ReCycle Bins in many stores such as Lowes & Home Depot, those things look like a disaster waiting to happen to me…. yet one rarely if ever hears of a problem.
I think you are good to go on your nicely done storage methods, exemplary in fact.
Could anything go wrong in your method of storage or any other of the things that have been mentioned??? Sure, stuff happens no matter the precautions taken. You could have a METEORITE fall through your roof tonight and hit you while laying in your bed. Chances are pretty astronomical that is not gonna happen to you though. Same as your well stored batteries are not going to spontaneously combust.
I mean check out below how they are pack and shipped when they are manufactured…………
It’s a subjective call and there is never a “totally safe” without there being a cost or loss involved. I wouldn’t worry much myself as long as I had somebody else who is both smart and reliable to deal with them in the event I couldn’t. An external fire would be overwhelming before it affected the ells, but a cell venting with flame could begin a cascading effect of large proportions. So at least you need a smoke detector near them and the door to that room needs to be always closed when not in use. And everyone in the house needs to know that when that smoke detector triggers, do not open that door and leave the house immediately, being sure to stay upwind of that room thereafter.
My relatively few cls aren’t stored in nearly as safe a manner, but they are relatively safe and I’ll upgrade my storage soon.
Regards silica gel packs, they do what they’re supposed to do well- absorb moisture- but in that, they are also concentrating moisture in that one spot and if they are in contact with anything, that moisture can transfer to it. They can also get dripping wet in a worst-case scenario. So keep that in mind when using them. I like mine to be in plastic containers with lids which have a few small holes in them. Moisture will still be collected but any excess can’t affect anything else. I’ve seen beautiful gun bluing jobs destroyed through rust caused by contact with silica gel packs because the user didn’t know any better. Don’t let that be you 
Phil
One last try. Base your family’s safety on something some guys on the Internets tell you??
Seriously, you can look this stuff up.
Those illustrated close-backed boxes of li-ion cells are the ones banned from passenger aircraft, and the cargo air pilots are petitioning for protection too.
Google for why.
Potential Hazards at Both Ends of the Lithium-Ion Life Cycle
IEEE Spectrum Mar 1, 2013
“One problem is that many lithium-ion batteries today contain fluorine, which … In accidental battery fires, HF is noxious, dangerous to the touch …”
“A battery recycling plant in Trail, B.C., went up in flames in November 2009….”
“In the European Union, containers of used lithium-ion batteries are filled with sand or the silicate material vermiculite to prevent the jumble of batteries from forming a circuit and sparking a fire en route to the recycler ….”
https://www.americandisposal.com/blog/lithium-ion-batteries
“…Lithium Ion Batteries are one of the leading causes of recycling truck fires.”
If you do have a house fire, for any reason, your insurance company is going to be interested in this topic.
Not directly but some time ago a helicopter of the Dutch army flew into a powerline and the village that was connected to it had no power for 3 weeks.
The worst thing people noticed was boredom, so I got serveral tomo powerbanks and 2 128gb flashcard with tons of movies, music, games and series that I enjoy.
I calculated that with 500 batteries I can power my phone for 10 hours a day for a month.
I also bought 10 of these empty powerbanks and 10 of these usb leds for lighting.
That is a great idea I just ordered 50 of ebay.
Thanks!
Started with my first sky ray king and me taking apart an old laptop battery of a friend of mine, when I saw 6 perfectly fine sony 18650’s inside.
You can say that at that moment I saw the light…… click me
Ammo cans is a great idea, gonna be looking into that, maybe even bigger aluminium boxes or a steel crate.
My living space is quite limited and I don’t have many places to put these batteries.
Only other option is to place them outside or digging a hole in the garden with a steel crate in it to put the batteries in, with a steel lid?
Do you really think such a 18650 can just pop his top by sitting in a plastic box?
Also thanks for the reading material!
I know what you mean lithium cells together with 9v batteries, thats the stuff of nightmares.
When I dispose of my dead 18650’s I always wrap them in duct tape from top to botom making sure when a 9v touches them nothing will happen.
Just put a lithium button cell on both + and - contacts of a 9v and watch the Bang.
Creepy
Yes. Crystal growth doesn’t always get initiated, but once it begins, from over- or under-charging or physical damage, the crystal growth progresses.
That’s why throwing them in the trash is a bad, bad idea. It can take a long time before the problem becomes obvious and dangerous to someone else.
https://www.google.com/search?q=lithium-ion+separator+crystal+growth
And, again, you don’t know what’s actually inside the shrinkwrap, don’t know whether the materials were well chosen or properly handled for longterm stability.
https://www.google.com/search?q=lithium-ion+separator+china+battery+fire
Thermal runaway caused fire and explosion of lithium ion battery
bbs.sciencenet.cn/home.php?mod=attachment&id=18661
by Q Wang - 2012 - Cited by 316 …. A separator is necessary … bus catch fire, Shanghai, China.
ok, really, I’m unsubscribing, I’ve said more than enough about this and I know people will want to argue that it can’t happen and won’t be a problem.
We all feel lucky. Almost all of us are, almost all of the time.
None of us bought a hoverboard, that I can recall. That was smart.
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How to Store Lithium-Ion Batteries for Lawnmowers
1 <> Place a lithium-ion battery in a climate-controlled storage structure, such as a shed or garage, or take it inside your house for storage. Lithium-ion batteries handle cold temperatures — down to 14 degrees Fahrenheit — better than warm temperatures. Extended time in a temperature above 85 degrees Fahrenheit can harm the battery’s performance.
2 <> Prepare a plastic or wood shelf to store the battery. Don’t place the battery on a metal shelf. If the battery’s terminals touch metal, the battery could overheat to a dangerous level.
3 <> Allow the battery to lose about one-half of its charge before storing it. Unlike older, nickel-cadmium batteries that function best when stored at full charge, lithium-ion batteries become stressed and lose functionality when held at full charge for long periods. Don’t store your mower’s battery on a battery charger.
4 <> Recharge the battery partially every two months. Recharging keeps the ions ready to work under a full charge when it’s time to mow again.
http://homeguides.sfgate.com/store-lithiumion-batteries-lawnmowers-96040.html
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Why lithium batteries keep catching fire
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For those who want to get really super serious about LI Ion Battery Storage .
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THIS would probably work also for the seriously safety minded hoarder of Li Ion Batteries.
I don’t recall even one person saying “that it can’t happen and won’t be a problem”.
Anything can happen, whether it be a cell phone, laptop, cordless tool, etc., etc.
That is helped by improper handling as well as improper disposal of Li Ion batteries. It appears to me the OP is doing things correctly. Does this completely eliminate all risk? Of course not. But as has already been stated, there is risk involved in most anything in life. Should we keep our cell phone stored in a fireproof metal box at night? Maybe, but how many of us actually do that?
There are more fires in gasoline powered cars with lead acid batteries (1 in 1300) than electric cars with Li Ion batteries (1 in 10,000). (if I remember those numbers correctly)…. So yes sir… stuff can happen.
How do you store your Li Ion cells ’hank’???
I store mine in little plastic storage boxes that either hold 2 or 4. Also in PowerPax holders and all of those are either on a shelf or in a cardboard box. It might all “fall apart” tonight… but so far so good.
When stored in metal it can SHORT out and the metal can become a pipe bomb which is much more destructive than wood! 
Wow. Great Scary Thread. Closer to Halloween it gets even Scarier.
_
POPCORN_
If anyone decides to use a Military Ammo Box, just remember you will need to drill some vent holes in it. Otherwise it would just be a bomb if things “went bad”.
Instead of drilling holes you could probably just remover the rubber sealing gasket from the lid.
I think most of us agree with what you’re saying Teacher. One can’t totally eliminate risk in many things that we do so all that can be done is to minimize it as much as possible. I understand where Hank is coming from but to eliminate all li-on risks means having no devices that use them or owning individual ones. From his posts it’s clear he has 18650’s, etc so in this case I think he’s disagreeing on the need to have so many batteries as oppose to having any.
Perhaps I’m misinterpreting his posts for which I will apologize in advance but coming across so stridently is the wrong approach to take.
I “think” I understand where hank is coming from also. I never read into anything he was saying not to have any Li Ion batteries.
He has presented the side of what can go wrong with Li Ion cells and there is no argument there from me.
I would not even say his approach was “wrong or stringent”.
He got his point across about Li Ion’s. Stuff can happen, and it can happen more readily when Li Ion’s are handled carelessly & stupidly.
Prime example being the picture in one of his links of the trash truck that was on fire because someone carelessly disposed of some batteries in their household trash. That would have never happened if they had been disposed of properly.
And no argument from me that if someone has 1000 batteries the chance of something going wrong is greater than with someone who has 10.
My point is that the OP told us how he “handles” his batteries and showed us how he stores them. He does not come across as a careless or stupid person. He comes across very credible in how he handles his Li Ion Batteries.
So personally, I think he is doing a stellar job with the whole thing… from testing them to storing them.
I doubt we will ever read about him in a Li Ion horror story. 
EDIT: The one thing I would personally not do is store them all fully charged, I would implement a rotation schedule.
Storing lithium ion batteries is like storing any other combustible substance; there is always risk. Danger can only be reduced.
The best safety feature is our frontal cortex and how we store and recheck safety precautions.
Thanks for your input people :+1:
I am gonna look for metal ammo boxes in which I can put 4 or 6 of my plastic containers with 18650’s.
Meanwhile I have mounted a smoke alarm on the inside of the wooden cabinet above the plastic containers with 18650’s
I have ordered silica packets and tiny glass bottles in which I will put the silica packets, one bottle per container.
I have chosen the 5ml bottles which are 18mm in width so I only have to take away one 18650 per container to replace with a bottle with a packet inside of course without a cork.
This will surely set my mind at ease.
Cheers!!
Time for an update.
Put 1 glass bottle with 3 grams of silica gel in each container.
And bought a steel office archiver with 6 draws with 2 container per draw
I couldn’t fit a smoke alarm inside but I’m looking for a thermo alarm.
If anyone knows of such a device please let me know.
That is really nice ‘Buzzing Bulb’!!!
I really like that metal case too. I could use a couple of those myself to hold various things. Did you buy it local or on line??
Thanks for sharing………. :+1:
Got it from Ikea, it’s called a Helmer and costs 29,99 euro
Thank you! Just ordered one…… :+1:
I appreciate the info.