Batteries the Focus of AT&T Investigation

An anonymous reader writes "AT&T is focusing on the batteries supplied by Avestor as the cause of its 2006 equipment explosion in a suburban Houston neighborhood. The carrier says it has 17,000 of those same batteries still in its network. Some photos of the equipment that was shredded in the blast are also available."

Comments

The real reason for the explosion?

[Lost Penguin]

All that NSA snooping equipment was designed to self destruct if proof was recorded that the Neocons were behind 9-11.....

Re:The real reason for the explosion?

[fataugie]

Shouldn't your tag line read:

"Resistance is Fertile; You will be inseminated"

Sounds alot like

[JamesRose]

"It's 1 year later, and we still don't have a clue waht the hell is going wrong, it could happen again any time, so what we're going to do is blame a relatively cheap component manufactured by a third party and replace it.

Re:Sounds alot like

[Anonymous Coward]

So going after the most likely cause, a rechargeable battery that vented hydrogen gas, is somehow wrong?

Cars blow up, too. And so do transformers filled with oil. And steam boilers at factories. Those are real disasters. I think this "reporting" is just a lame attempt at mudslinging AT&T.

Re:Sounds alot like

[JamesRose]

The cause of most explosions are explained before they've even been cleaned up (I don't mean, oh, its a bomb, I mean the actual chemicals invlovled etc) even if they are looking at the right thing now, they are shockingly slow at investigating.

Re:Sounds alot like

[Firethorn]

My thought would be: What else in the cabinet could cause such an explosion? I mean, the equipment should be fused; there should be enough circuit breakers and fuses in the lines to prevent electricity from creating such a large bang; so a short or capacitor shouldn't do it. Properly constructed circuit boards aren't even all that flammable, much less explosive enough to destroy a cabinet.

What's the most reactive chemical area around? The battery. It's a lithium type - and warns that it could catch fire/explode if damaged.

It's certainly not a 'cheap component' - it's stated to be more expensive than other battery types.

Re:Sounds alot like

[nacturation]

I think this "reporting" is just a lame attempt at mudslinging AT&T. And this so-called reporting is extremely juvenile. From one of the photo captions: "Here's what AT&T saw as it rolled up to the scene of the explosion. Imagine if that hunk of fence had been some old cougar weeding her garden. Would have left a mark, no?" Very mature, guys.

Re:Sounds alot like

[dsgrntlxmply]

The component in question is anything but cheap. As others have pointed out, there is nothing else in the cabinet which 1) stored that much energy, and 2) had any possibility of releasing it that quickly.

Historically, outside plant equipment cabinets have used lead-acid batteries. These have their own problems, but they are physically quite robust, and do not explode unless they are grossly abused. Yes, they do release H2 under some conditions, but this is a known factor in the cabinet design space.

One might examine the wisdom of serving lifeline POTS over DSL or cable, which require close-in standby power due to limited reach. I cannot see anything else which would compel batteries in the cabinet. If the power is out in the neighborhood, not many people will be watching TV or using the Internet. I doubt that this cabinet itself contained any equipment to directly serve traditional baseband POTS, and DSL splitter/combiners typically are passive; the POTS circuit will function even if the DSL equipment loses power.

Perhaps I'm just old-fashioned, but under classic Carrier Serving Area design rules, digital loop carrier (POTS remote equipment) cabinets can be located 9000-12000 wire-feet away from the subscribers. With that working distance, size constraints on the cabinet are somewhat relaxed, and the cabinet does not need to be sited next to someone's garage.

Perhaps I am just bitter (and I had a direct stake, so this is a biased claim) that better structures for delivering VDSL triple-play alongside backup-powered lifeline baseband POTS, were available by 1999. Sadly, amidst the bursting bubble, these were mostly bypassed by the telcos in favor of waiting for what turned out to be this amazingly silly eyesore of an energetic kludge, plopped within striking distance of someone's garden fence and garage.

At least no nipples were damaged in this incident, as compared to: http://believe-or-not.blogspot.com/2007/07/cell-ph one-explodes-and-burns-off.html

Re:Sounds alot like

[WarlockD]

I did a call over at the old SBC building in Fort Worth. You should see their back up batterys.

They are just big vats of acid in thick glass jars with electrodes. All sorts of acid warrning sticks around the building too.

Re:Sounds alot like

[v1]

Elecrticity does not explode. Most electronic equipment does not explode. Only electronics that contain chemicals that behave badly when exposed to heat, pressure, etc. Capacitors and batteries both store large amounts of energy in a chemical state, (which can change to gasious) and are the primary "explosives" in electronics. A sufficiently high current in most anything will cause rapid expansion of air however, which can make semiconductors explode, but not on nearly so grand a scale as this. I've seen solid state relays send their tops flying across the room and dent a cabinet when they shorted out. I don't know if I would consider that an "explosion".

The only thing in those cabinets capable of so much as blowing a door off the cabinet (let alone launching it) are the batteries. I was looking through the pictures for something else that I was very surprised I did not see. Most chemical batteries use metal (lead) plates suspended in a medium (hcl) and when a battery goes off, it usually blows the top and sides off, and sends plates (and hcl...) flying in all directions, leaving the base of the battery just sitting there where the battery was. A car battery that blows up standing in the open can send lead plates for 20 feet in every direction and will rain down along with the hcl, not good to be around them when they do that. (and then you are treated to an eerie sizzling sound coming from all directions as the HCL starts to eat into anything it splattered onto, which can include your clothing)

Car batteries tend to explode when their production of hydrogen and oxygen during charge mixes and encounters an ignition source / spark, which may or may not have been what happened in this case, it would depend on what sort of batteries they used. Almost certainly "sealed lead acid gell cells" - that's what's in your UPS, and that's why the cabinet had batteries. A spark is the best bet - altough high heat can also ignite volitile gasses, it requires a great deal of heat that is not likely to be in the cabinet unless there is a serious electrical short.

I didn't see pictures of the surrounding area, nor did I see the bed of the pickup that held all the bits they picked up, I wonder if the photographer just didn't realize the significance of the flotsom scattered around the box?

Fuses won't prevent this problem - they may have stopped the ignition source this time, but if volitile gasses are allowed to accumulate, something is going to set them off eventually, even if by static electricity or the spark in the hinge of the outer case as it's being opened by a tech.

As for the fire, hard to say. Insulated wire tends to burn very well, a bit like a dry brush pile.

Re:Sounds alot like

[Firethorn]

I work for the Department of Redundancy Department.

You most certainly do, seeing as how you mostly managed to restate what I said.

Elecrticity does not explode

No it doesn't, but under the right circumstances it can heat something so fast and hard that it effectively explodes. Saw/heard it once when they tried replacing a fuse on a power line that had shorted closed next to our building(we were on generator at the time). It sounded enough like a gunshot to make me duck.

which can make semiconductors explode, but not on nearly so grand a scale as this.

My point. In order to get the other components in the cabinet to 'explode' at such a scale would require modification to the point of being obvious; or more likely access the physics labs that make things like hundreds of thousands of volts available.

I was looking through the pictures for something else that I was very surprised I did not see.

Nice long rant that missed the type of battery in the cabinet completely. It says right in the article that the batteries we're talking about are lithium-metal polymer (LMP), built by a bankrupt company by the name of Avestor. It's a solid state battery meant to last for at least 10 years. Oh yeah, and anybody moving them around should have hazmat qualifications as they can catch fire if they get too hot or 'become unstable' if damaged by movement.

Re:Sounds alot like

[v1]

Just because a battery has Li in it does not mean it's dangerous to handle. (at least, not if it's designed sensibly) Most laptop computer batteries nowadays are LiIo which is not too different.

Yes the primary fuses on the poles can be spectacular when they go. Again you've got a conductor (fusable link) inside the cartridge and when the power co cuts in the mains and there's still a short (which can be hard to tell in advance) the link basically vaporizes instantly and superheats the inside of the cartridge, causing it to explode. (this is actually a good thing, the alternative is the transmission lines or transformers melting) Sends bits of the cartridge in every direction at high velocity, that's why they stand back when they are cutting power back on. ;) Although I realize this is technically an explosion, I don't usually think of it that way - I usually consider things like TNT, gunpowder etc to be explosives. Maybe there's another more specific name for explosion due to sudden thermal expansion due to current inrush? I have a video of a primary fuse going at a substation during a fire, all you get is a blinding white flash and what sounds like a cherry bomb. The sound wave hits you a second after the flash like someone just gave you a really good whollup in the chest with a large pillow.

If you have a strong attention span you can observe other things in the area when this happens. The feed lines actually twitch. It's really freaky. (I've been told if they're laying on the ground they can actually jump an inch or so off the ground in places, haven't had that pleasure myself) Having all that movement around you at the same time as the flash and the explosion would have to really rattle you.

Re:Sounds alot like

[Firethorn]

Just because a battery has Li in it does not mean it's dangerous to handle. (at least, not if it's designed sensibly) Most laptop computer batteries nowadays are LiIo which is not too different.

I was just relaying the recommendations placed in the instruction manuals by the company that made the batteries. Oh, and it's not like laptop batteries have a perfect safety record either.

They may be similar, but from my understanding, laptop LiIon batteries still use electrolyte, of with the presumably exploded battery didn't have.

As for the high voltage stuff - you're right, it does have some interesting effects, yet personally, I'd prefer to see them in lab videos. Still, this cabinet shouldn't see anything more than 240 volts at max, and 120 would be more likely. Fuses should blow long before voltages get to the levels needed to make even a bang audible outside the cabinet.

Re:Sounds alot like

[v1]

Fuses should blow long before voltages get to the levels needed to make even a bang audible outside the cabinet.

Rising voltage does not blow fuses. Rising current does. Rising voltage actually makes fuses blow at higher current levels than they should, which is why you have to use special fuses in high voltage circuits.

Re:Sounds alot like

[Firethorn]

Rising voltage causes circuitry to use more watts, leading to more current, leading to the fuses blowing.

It's not ideal, but it's better than nothing. Of course a circuit breaker designed to trip on overvoltage is a good idea as well.

Re:Sounds alot like

[csirac]

Wow, you are being very picky today. Saying that "rising voltage does not blow fuses, rising current does" is irrelevant... There was nothing technically wrong with parent's observation on the behaviour of protection circuits when presented with excessive voltage. Who knows, a transient voltage suppressor may be protecting the load as well as that fuse, and the TVS may provide that current to make the fuse blow on over-voltage.

My background is admittedly low power engineering, albeit in hazardous areas (intrinsically safe systems where there's explosive gases in the air). As for utility power transmission lines, I'm pretty sure those fuses are usually designed so they don't spray shrapnel everywhere. Particularly at substations the line fuses are quite exotic, composite fuse links (involving silicon), immersed in spark-arresting gases and so on. On the LV side of some plants I've seen them use two different types of fuses in series - one to interrupt "dead-short" type over-current, and the other for more gentle 200% overload situations.

But all this talk of how fuses work is... redundant? These cabinets are using unstable batteries that do require precautions to maintain a safe working life. I can tell you that in IEC Zone 1 and Zone 2 hazardous areas (these might exist at mine sites, chemical processing plants, petroleum refineries, etc), it's very difficult to certify lithium batteries in this environment - they are just not trusted. A certified Lithium battery has electronics to protect each *cell* of the battery: monitoring internal pressure of the cell, temperature, preventing discharge below a safe voltage, preventing overcharge to above a safe voltage, and of course solid-state current limiting, as well as fused protection. And did I mention that's on each cell inside the battery? Because all it takes is one faulty cell to really, really ruin your day.

I don't understand what there is to discuss... unless someone blew it up with explosives, the unstable batteries in the compartment lacked sufficient internal protection circuitry to prevent explosion. Maybe a faulty charge circuit coupled with a dud thermal fuse in the battery (or all the batteries, if there was a faulty batch) caused all the cells to heat up, internal pressure exceeded casing maximum, it vented flammable material which ignited, starting a chain reaction by igniting the rest of the cells/batteries that were already just about boiling and ready to pop.

Energy Density

[Detritus]

Stuff like that happens when you put a large amount of energy in a small volume. I've seen pictures of helicopters that were destroyed when their ni-cad batteries went into thermal runaway due to an electrical fault.

Re:Energy Density

[Detritus]

What's your major malfunction?

The problem with ni-cad batteries is real, see Federal Aviation Administration Advisory Circular 00-33A, "Nickel-Cadmium Battery Operational, Maintenance, and Overhaul Practices".

Re:Energy Density

[dougmc]

These sorts of problems generally aren't specific to NiCd batteries.

In any event, the problem with LiPos is that the batteries themselves are flammable. With NiCds, they can turn into hot steamers, or can cause fires by getting so hot that they cause whatever is next to them to burn, or can fuel a fire by feeding a short circuit somewhere else, but they themselves don't burn. They can vent so violently that they sort of explode, but there's no fire involved. Note that the chemistry of NiMH cells is similar enough to NiCd cells that they generally behave pretty much the same way.

But either way, if you abuse your batteries, bad things happen. And as a general rule of thumb, the higher the energy density, the worse the bad things are.

Hold the phone....!

[r_jensen11]

Where's Sony in all of this? Oh a serious note: I hope this isn't related at all to the Sony Ericsson T637 I just bought....

Re:Hold the phone....!

[CyberKnet]

The Sony Ericsson phone you just bought is defective by design. A google search will show up numerous complaints of no/low signal, slow software, and inability to hold a call. Contact Jennifer Atwood (manager of their customer service department) to have it replaced with a functioning model. If you do not get a positive result, you can always email the president of Sony-Ericsson worldwide... he listens and gets things done. Email me and I will send you specific contact details for people at Sony Ericsson who got things done for me... nobody should have to be stuck with the "phone" Sony Ericsson refers to as the T637.

Re:Hold the phone....!

[r_jensen11]

...and what do you mean is a functioning model? I specifically bought this phone because of bluetooth and camera. And would SE actually replace a phone that I bought off of ebay?

U-verse,

[ThatsNotPudding]

Blew-verse; it's all good.

I assume

[Z00L00K]

that they have ruled out the local prankster or animal intrusion.

It's not surprising that batteries can go ballistic. That happens now and then.

From what can be seen from the pictures the design wasn't sufficient to contain the batteries and any possible cause for explosion there. Maybe the designer didn't think about that or wanted to do a cheap job.

Back to NiCad

[philpalm]

Even though the investigation isn't over,the replacement battery for Li Polymer(whatever) will be NiCad (using a subsidary (of course)). They have a proven record of being reliable for ten years. However if there is still a tendency to explode, burn, melt such battery vaults should be made stronger(and maybe more tamper proof). Is it such a slow news cycle that any exploding Li battery news again?

Re:Back to NiCad

[Anonymous McCartneyf]

It's news to me.
Transformers do explode every so often (though not too often), but it's usually because of really bad weather or electrical power-line snafus. Phone transformers exploding because they contain batteries which are developing a history of being explosive--which likely wasn't known when the transformers were commissioned--is news.

Re:Back to NiCad

[dougmc]

The replacement for LiPos will not be NiCd batteries.

NiCds have a much lower energy density than LiPos -- which is exactly why people use LiPos rather than NiCds. The self discharge rate for NiCds is higher as well, and they need a little care taken when charging them to prevent voltage depression (well, many people call it memory, but that's another thing entirely.)

If LiPos are to be replaced, A123 batteries are a more likely replacement, though for things like this where weight and size shouldn't really be a premium, I'm surprised they're not just sticking with the tried, true, reliable and relatively inexpensive lead-acid or gel-cell batteries.

Another problem NiCds have is that they're made with chemicals that are toxic to the environment. NiMH also have a higher energy density, and these two things have made NiMH more popular than NiCd batteries. But NiMH cells do have some disadvantages over NiCd -- higher self discharge rate and higher internal resistances come to mind.

Re:Back to NiCad

[dougmc]

The replacement for LiPos will not be NiCd batteries. ... or maybe I'm wrong. I'm familiar with the sealed NiCd batteries, but not really with the flooded variety which appear to be as good a fit for this sort of thing as Lead-acid batteries are. (The sealed ones don't appear to be quite as good of a fit.)

Awesome case mod !

[Anonymous Coward]

See...
http://www.lightreading.com/document.asp?doc_id=13 1210&page_number=1&image_number=8&site=

for a totally over-the-top case mod. It's Unreal meets Terminator.

Hydrogen + Spark = Bad

[effigiate]

I'm not sure what types of batteries they were using, but standard lead-acid batteries vent hydrogen during charging. If you don't make provisions for the removal of it and it builds up in the cabinet, one tiny spark and you've got yourself a little bomb sitting there.

Re:Hydrogen + Spark = Bad

[Anonymous McCartneyf]

And the phone lines are near the power lines, so lots of opportunities for little sparks...
But I hear that the batteries in question are li-poly. I don't think they vent hydrogen; they just appear to have unfortunate internal similarities to C4 explosive when they're made wrong.

Re:Hydrogen + Spark = Bad

[NoMaster]

Not so much of the "little sparks"; yes there are relays still inside that sort of gear, but they're reed relays with the contacts sealed in a nitrogen atmosphere.

What you do find, however, is cct breakers and contactors on the main power feed & internal distribution. But the usual explosive trigger is the sparks from the cells themselves as they self-destruct...

We used to get 1 or 2 incidents like this a year in Aus, mostly in the far north. The SLA batteries used here don't take kindly to temps above ~ 35C (easily found inside cabinets even in colder areas) - battery life is dramatically reduced, and the usual failure mode is thermal runaway causing internal shorts &/or case splitting. The end result was usually just acid vapour destroying everything inside the cabinet. Occasionally, as I said, we'd get one that went boom.

It certainly wasn't unusual for the batteries to to from "visually OK, passes all discharge / internal impedance test" to "case on the verge of rupture" in as little as 1 month. We usually checked them every 3 months, and that was considered by both the manufacturers and my superiors as "excessive".

Having said that, what freakin' idiot decided Li-Pol cells were a good idea in that sort of environment! The things are barely stable at room temperature, requiring very careful feeding and care of charge / discharge rates even then (which is why every single consumer-use Li-Ion/Pol battery sold has a charge controller & thermal monitor cct built-in to the battery itself). Essentially, from a non-technical POV, Li-Ion & Li-Pol cells are little containers of metallic fire that will self-destruct at the slightest provocation. I certainly can't imagine any really safe way of using them in a online / continuous float application like that...

(Ex-telco senior switching, CAN, and battery maintenance tech.)

The Secretary will Disavow any knowlege.....

[Newer Guy]

Did anyone see Ethan Harris in the area?

Re:China: Possible Source of Problem

[DaleGlass]

That'd be very unsurprising, but not terribly enlightening.

I don't remember ever seeing a product "Made in America". Nearly everything comes from China these days, including the vast majority of the things sold under american brands.

Re:China: Possible Source of Problem

[DDLKermit007]

Just one more reason I am wanting to move out of the US. Hell I just got back from Japan a few days ago after a months vacation. You know how much stuff I saw that said Made in China on it? Very little, at that it was usually cheap crap like stuffed toys. Most everything I saw in that country was made in Japan. Something about quality and a little national pride. Oh how I wish the general populous of the US cared about either. Stuff usually cost at max 10% extra. Which is more than enough imo to know someone nearby that actually could care about their work actually made what you just paid for.

All the pictures

[TubeSteak]

http://members.home.nl.nyud.net/bas.de.reuver/file s/fusker.html?http://img.lightreading.com.nyud.net /2007/08/131210/14%5B44-62%5D.jpg

The first pictures is 'before'
All the rest are 'after'

Re:China: Possible Source of Problem

[Dogtanian]

You know how much stuff I saw that said Made in China on it? Very little, at that it was usually cheap crap like stuffed toys. Most everything I saw in that country was made in Japan. [..] Oh how I wish the general populous of the US cared about either. Stuff usually cost at max 10% extra. Is all that true? I have a Japanese friend, and she was apparently quite shocked (and annoyed) when she found out that her Nintendo DS was made in China.

Personally, I assumed she just hadn't been paying attention to how much stuff was made in China these days (we have a lot of it in the UK), but maybe what you say is right.

Re:China: Possible Source of Problem

[ScrewMaster]

No kidding ... for several months while I had AT&T Broadband for cable service I never could get a decent picture. Internet speeds were nothing to write home about either. Techs came out a number of times (usually contractor types, not AT&T-trained) and one of them put in an amplifier. Which worked just fine at amplifying the noise (and he stuck $90 on my bill.)

Finally I called to cancel my service because I wasn't getting that for which I was paying. The operator convinced me to give them one more try ... I said OK. Next day (a Sunday, believe it or not) this cherrypicker truck pulls up, with AT&T emblazoned on the side. This time I got a technician that had been through AT&T's in-house training program and wasn't afraid to get off his ass and climb a few poles. So he spent about three hours going down the street, pole-by-pole, until he called down and said "Whoops! Here's your problem" and tossed down a few feet of burned and blackened cable with squirrel toothmarks all over it, right down to the bare copper. It was a mess. So he replaced the cable for the whole block and we all got a great picture (and I got my 4 mbits/sec back.) Guy was pretty cool, really knew his stuff. It was like dealing with the AT&T of old. He also took the price of that stupid wideband amp off my bill -and- let me keep it! So I kept my service for a few more years until I moved.

I never found any squirrel bones, but I hope the 90 VDC feed cooked the little bastard.

Batteries.

[Al Young]

It's quite amazing that we still have problems manufacturing 'safe' batteries.

Anyone else remember the issues with Toshiba/Sony/Apple laptop batteries?

'Close your eyes and you'll burst into flames'.

Re:Batteries.

[Repossessed]

Dell and HP batteries too. *Everybody* was using the things Sony was selling.

Re:Batteries.

[iminplaya]

It's quite amazing that we still have problems manufacturing 'safe' batteries.

There is no technical problem in doing so. It's strictly a matter of economics.

Re:The sad thing is, someone's going to mod you up

[feed_me_cereal]

no... they'll mod it "funny" because he was making a *joke*, and pretty much every lame joke gets modded funny on this site.

BTW, you can chill out, because despite about 50 bagillion submissions (mine being one), the story about AT&T censoring pearl jam's anti-bush lyrics never made it onto slashdot (at least, I haven't been able to find it anywhere), despite it concerning net neutrality and webcasts, and despite it being on the front page of google news for 3 days straight. Things aren't quite as slanted as you percieve htem.

Just Perfect

[JackSpratts]

gee. not only are they ugly but potentially deadly too.

these are significantly large, noisy cluster boxes that under existing statute att feels can be installed anywhere, at the end of driveways in front of private homes etc. we now have these all over town and are currently involved in negotiations w/att to minimise their aesthetic impact.

now i suppose we'll have to go back and negotiate their explosive impact too.

vrad box walk-through

http://www.youtube.com/watch?v=m1o-1MkvzK4

check put the fan noise. this box is producing a lot of heat.

"And then down here is the battery back-up ."

- js.

Cougar?

[iminplaya]

Where can I find one of these feline gardeners?

Re:China: Possible Source of Problem

[jafiwam]

That wasn't AT&T.

That was an impostor. Probably a PI or the CIA installing a data trap on your line.

How do I know this?

Nobody from AT&T is that competent.

Re:China: Possible Source of Problem

[ScrewMaster]

AT&T itself trains some pretty good people. Unfortunately, they no longer train enough of them (particularly when it came to the original AT&T Broadband rollout) so they resorted to the use of outside contractors. Most of them were pretty useless.

Of course, it's not just AT&T. I also had Dish Network for a while, and I had to have them come out four times, different contractors each time, before I could get one that could figure out how to install the dish on my house. It was a tricky install I admit, trees and roof angle and so forth. One guy wanted to trench my lawn and install a concrete base with a pole on it. Finally a Russian guy and his son came out, they were properly equipped with survey equipment and an air of general competence, and had the damn thing installed in twenty minutes. Worked fine ever since.

Get used to it, it's going to get worse.

[HornWumpus]

There are all sorts of economic forces in play pushing for higher energy density batteries.

I can't tell you what's next, battery technology wise, but it will have more explosive potential then Lithium batteries.

In 100 years kids will deliberately short small batteries to make them explode. Unless the world comes to it's senses and continues to allow access to guns and reloading supplies. In the areas that do lucky kids will continue to blow things up the old fashioned way...When I was a kid, we made our own black powder with salt-peter from the drug store...and we liked it.

You canna change the laws of physics.

Re:The sad thing is, someone's going to mod you up

[operagost]

Th funny thing is, censorship has nothing to do with net-neutrality!

Texas A&M

[Joseph_Daniel_Zukige]

mascot.

Not Texas A&M, U of Houston

[Joseph_Daniel_Zukige]

My Aggie brother in law will never let me live this one down.

(If he ever reads it.)

(erk.)

Flywheel Batteries

[F34nor]

Such high power densities, so little chance of explosion, so little maintenance.

Re:Flywheel Batteries

[philpalm]

Huh? With the centrifical forces in a flywheel battery you can have a different type of explosion, the force of pieces flying off at high speed is still deadly.

Re:Flywheel Batteries

[F34nor]

It takes a huge force to penetrate the casing or to throw the wheel off the gimbals. Not only does it not happen very often but without blowing up the spacecraft that carries it or running a big sharp pointy chuck of hardened steel into it it seems easy to avoid. If you are using this for a battery for a house a business or a telco you can even bury them in the ground so if they do have a problem its no big deal. Caterpillar makes them for god sakes.

They now coat internal surfaces with nylon, if the flywheel does go off track it pulls a bead of nylon filling the case with sticky hot nylon stringer causing the wheel to seize.

Either way they are reliable enough to send into space at $10,000 per pound to orbit so they are good enough for a data center.

Re:The sad thing is, someone's going to mod you up

[feed_me_cereal]

it concerns net neutrality because it shows that AT&T cannot be trusted with power over the internet. This is a case of them abusing such power. It's not the same power they would have if they could determine what gets to flow through their pipes, but it all comes back to whether or not we can trust them with that power. This is why people would talk about net neutrality during all the wire-tapping shenanigans.

Re:China: Possible Source of Problem

[DDLKermit007]

Yes, videogame systems are made in China. Thats the major caveat with Japan. The competition to keep prices down in that area is too great.

Re:China: Possible Source of Problem

[Dogtanian]

Ah, thanks.

Not a cheap component

[tcgroat]

The batteries implicated in the fires were advanced, very expensive lithium-metal-polymer types developed and built by Avestor. They were built for long-life outdoor installations: rated for -40C to 65C, temperature regulated, self monitoring: these were no low end batteries! AT&T retained an independent failure investigation quoted here, which "...found that the battery design was sound, as were the safety features, and concluded that the risk of hazardous failures with this battery is as low, if not lower, than the risk with alternative batteries, which are used by other telecommunications and cable companies in similar applications."

While the technology was impressive, the business was unprofitable and Avestor closed in 2005.

Houston is hot as Hades

[jac_at_nac]

Another item of mention is the heat build up of that area. To quote Matthew Broderick...."It Africa Hot, Tarzan couldn't take this kinda heat." I live just North of Houston and it's unbearable in the late summer months.