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Discussion Starter · #1 ·
I've closely followed the discussion regarding Li-ion and Li-Po batteries for some time. Now that we're seeing the commercial versions of these batteries having recharge cycles measured in thousands, the affordability of these batteries is becoming very attractive. So too do we see the advances in the charging safety technology through the introduction of the cell balancing pig tail and balancing devices that cost under $10.

But, unlike the RC plane folks which have been the leaders in causing the batteries to get safer, we rarely remove the battery pack from the engine when we charge them. The RC plane guys I know, remove the battery pack, plug in the charger and balancing device, put the pack in a ceramic jug that has a lid, and turn on the charger. That way, if a cell shorts, you contain the fire inside a fireproof "vault". And, to make the charging process even safer, many are putting their charging jugs outside the house...with the charger in the jug too.

Now, given all that, has anyone thought about what an outdoor charging station would/could look like for a engine with batteries or a car with Li-ion/Li-Po batteries in it? Anyone got any examples?
 

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My Li-Ions are charged inside the loco (tender or railcar). I charge them in my garage on the bench. I built a little crib for them to sit in made of Hardi-backer-board. I figured this cement-like material is probably more fire resistant than wood is. ??? I may be wrong, but I think the majority of the concern with fire is with the Li-Pos? I'm no expert here.
 

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Discussion Starter · #3 ·
OK...a crib...is there a top? The reason I ask is that I've seen 5' tall flames come out of a Li-ion/LiPo battery being charged...and it is those flames that get the house burning. But, HardiBacker sounds good...and perhaps an outdoor GRR building lined with HardiBacker would make a good place to run the loco's into for charging.
 

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Strange. The first post I made never appeared.

Oh well.

I make all installs with removable batteries now. That way I don't have to worry about a charging plug on the tender. If I want a longer run, I can always just put in a fresh battery, although I've never run out yet. ;)
 

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Posted By Mike Reilley on 03/13/2009 10:51 AM
OK...a crib...is there a top? The reason I ask is that I've seen 5' tall flames come out of a Li-ion/LiPo battery being charged...and it is those flames that get the house burning. But, HardiBacker sounds good...and perhaps an outdoor GRR building lined with HardiBacker would make a good place to run the loco's into for charging.

So, I'm still trying to learn about Li-xx's. Was it a Li-Ion battery you saw flaming or a Li-Po? Are they both equally dangerous? And, I am assuming they are only dangerous if the protection circuitry fails. If you are using cells without protection circuits, I think you are probably taking a big risk, correct?

No top to the crib. I was only concerned with the underlying surface. But obviously, this may not be enough.
 

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Any and all Lithium technologies have the same potential for thermal runaway (a Thermal run away situation refers to a FIRE or a condition where an increase in temperature (poor cell construction techniques and or materials, physical damage, shorts internal or external, high discharge et al) changes the conditions in a way that causes a further increase in temperature leading to a destructive result). Yes charge/discharge protection devices minimize the risks associated thereof outside sources (shorts and charger/user shortcomings), however other considerations exist such as physical damage to the cell and or battery, internal shorts and elevated operating temperatures to name a few. So be careful, there are many documented cases of Lithium cell failures ultimately with fire ensuing.

Lithium-Ion cells also incorporate a mechanical device known as a PTC, this device helps protect the cell by opening the electrical path and venting gases much like a safety release or pop-off valve. The PTC affords protection from internal cell failures or shortcomings and outside influences such as temperature.

It’s a GOOD idea to have a fire extinguisher present and near your charging and operations area just to be safe! A Halon extinguisher is recommended to quail the fire, while water based fire fighting methods are used to cool the cells to help prevent additional cells from disintegrating.

An ancillary electronic protection device cannot stop disintegration once a single cell or cells are in a thermal runaway mode. Nothing can stop thermal run away once triggered a small explosion is not uncommon either.

A charging station vault or enclosure is well suited to protect your home/shop. There are many materials that would serve well; Hardie Board is one of them since it’s comprised primarily of sand with some cement and fiber. The idea is to completely enclose the battery, locomotive or trailing car.

Regards,
Michael Glavin
 

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I charge mine in a hardiboard box, sometimes, but it just sits overtop of the loco/tender to prevent flame spread and spray. To be honest I wouldn't be heart broken if my garage burnt down, but thats another story. My question is this; I just read through the charging instructions for my new laptop, which has a Li Ion battery. Nowhere does it state that it needs to be charged in a flame proof box. The battery is in a small plastic case which can't be anymore fire resistant than the shell of my tender. Same thing with my cellphone, Li Ion battery no flame proof encloser recommended. Granted the cell phone battery is smaller but the laptop battery is darn near the same thing. So, why the difference? Do they think us DIYers are gonna kill ourselves? Or are they just being over cautious? Just about everyone owns a cellphone lots of people own laptops you can't tell me they all read the instructions and charge them exactly the way they are supposed to. My wife leaves her cell phone and once in awhile the laptop plugged in for days. The actual number of fire related incidents compared to actual number of devices owned is very low. As far as mishandeling, my poor cell phone has been through **** and back again, it's been dropped from high and low heights, (by high i mean over 60') it is out in the freezing cold and rain and has had the front screen melted off. The screen was replaced but it has the same battery, and no problems. I am by no means saying that this is right. I would assume that Lithium technology is the same. My phone doesn't have some "special" expensive battery in it, I would guess it has the cheapest battery that would pass their standards. So why can one battery be abused and the other need to be treated like gold? Again, I am not saying to do this, I still (usually) practice safe charging methods with my trains, but it just makes me stop and think.

Terry
 

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Terry,

Good questions, several reasons come to mind cell phones, laptops and the like have integral dedicated devices all of which are not necessarily user controlled thus eliminating end user interaction. That said there are many stories of laptop and cell phone melt downs out there (due a search on Google). The Lithium technology learning curve was pushed hard; many OEM’s had failure modes and massive recalls ensued… And cell phones use a single cell Li-Po’s, so the potential is reduced due to single cell count. Laptops as you suggest are similar to our uses in great numbers too. Something that’s not mentioned often like many things in our world you get what you pay for, in an effort to reduce cost some manufacturers use the minimal specified material quality and or quantity to reduce cost and possibly weight, the end result is cells with higher internal failure modes.

I suspect there are those out there that are represented in small numbers that simply don’t heed safe handling advice and ramble along with nary a worry, its these individuals that do it there way that know more than the Engineers that design and test this kind of stuff that present concern IMO. Stuff happens!!!

Lithium cell technology is safe; you just cannot become complacent with this stuff! We should all be aware of the proper safe care and feeding of our lithium batteries as well as the potential for failure modes.

Regards,
Michael Glavin
 

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I certainly believed you Mike. But yes, these videos are very enlightening! I guess I'll be building a box for my charging station. Better safe than sorry. In our situation (charging train batteries), who knows what combination of battery cells and chargers will come together. The little Chinese guy on the web page says its OK, but is it really?

But what about all the laptops laying around the house? Not really practical to charge them in a box. I guess they are in a more controlled environment, as far as mating the proper charger to the battery pack. And then it comes down to statistics ... yes it has happened in the past, but what are the odds now? Everything has risk associated with it. The question is ... how much?
 

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Posted By Michael Glavin on 03/13/2009 3:50 PM
{snip...}[/i] Lithium cell technology is safe; you just cannot become complacent with this stuff! We should all be aware of the proper safe care and feeding of our lithium batteries as well as the potential for failure modes. {snip...}


That's why every demolitions instructor I ever had while in the U.S.M.C. drilled it into our heads "Familiarity breeds contempt, don't take things for granted, else what's left of ya' gets planted"
 

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Just did a check on the Hardie board website and found this about fire resistance: Hardie Board

Looks like it is rated for 1-hour fire resistance. This should be a pretty good material to use on a charging box, especially since many of us already have this stuff and know how to work with it. But there may be better stuff out there. They mention Type X, fire-rated gypsum?
 

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Del,

Type "X" gypsum is fire rated gypsum board or sheet rock. Rated G.B. is resistant to fire not impervious. UL has "listed construction assemblies" that are designed to hold fire back for 1-hour. My company builds 1-hour rated equipment rooms regularly typically it requires two layers of 5/8 “X” G.B. sandwiched over wood or sheet metal studs or members much like typical wall construction.

I’d suggest the Hardie Board is a better approach in of itself…

Regards,
Michael Glavin
 

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Been charging all mine (6) on my work area desktop since they have been out. 2 Aristo chargers and 6 Aristo li-ion 22.5-volt batteries.
All my batteries are removable so I can just swap them out for loco when needed.
Most are set up in parallel for longer run times. I use the diode so they don’t back feed each other

Never had an issue.

KC
 

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Discussion Starter · #15 ·
How about using a rural mailbox? The jumbo ones (T3 sized) are 2' D x 1' W x 15" H so they'd hold a good sized car, tender, or smaller engine. Smaller mailboxes would easily hold the battery and charger. You'd have to put some kind of latch on the door to keep it shut if there was a fire.
 

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Mike,

A mailbox sounds interesting. But to be honest I like the idea of removing the batteries best… I got in the habit of pulling batteries and will likely continue with Lithium.

KC,

The “diode” is wired into a harness or on the batteries? Not sure why you’d need a diode, are you concerned about cross charging?

Regards,
Michael Glavin
 

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Diode is wired into each of the battery feed wires before parallel hookup, two or more batteries wired in parallel need to have same charge on each, if not the battery higher charged battery will try to charge lower charged battery an bring it up to equal charge, and this can damage the batteries.
Greg E did a lot of explaining about this.

KC
 

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KC

Thanks for sharing. I thought cross charging was likely the reason for the diodes... I've done a bunch of testing to validate or not cross charging myself, I'm going to ponder cross charging for train applications and start new thread with some questions.

Regards,
Michael
 

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In Re: Li-Ion laptop computer batteries catching fire.: A year or so ago (?) Toshiba issued a recall of some of their laptops because of a class-action suite against them claiming fires were not uncommon due to the Li-Ion batteries and the charging circuits. As I recall the Settlement was that Toshiba offered us $1000 towards the purchase of a new laptop (you had to return your old laptop to them) or a $500 check if you kept your old unit. I kept my old one. I do know that mine gets VERY HOT when I recharge the battery pack , so I keep it isolated from anything that might be flammable.
"Some more fuel for the fire, eh?"
 

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Posted By CapeCod1 on 04/07/2009 7:11 PM
I do know that mine gets VERY HOT when I recharge the battery pack , so I keep it isolated from anything that might be flammable.
"Some more fuel for the fire, eh?"





It sounds to me like you need to purchase a better charger. It sounds like it is charging at a very fast rate without the proper protection. Are you supposed to be using a temperature probe with it? What charger are you using?
 
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