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Comment Re:Fastest growing share is easy when you start at (Score 1) 382

If they care about battery longevity, they'll keep them between 20% and 80% SoC. (30:80 would last even longer. 80% DoD is still a decade of cycles) Getting to 80% SoC can, indeed, be done in 15-30min -- if you have nuclear power plant in your back yard. (we're talking many MW to charge a fleet of buses. One bus at a time... Just. No.)

The smallest office building I've been in was fed with 6000A 600V (3ph) service. (I don't know about the current office. We didn't have to build anything in it.)

Comment Re:Cheaper? (Score 1) 382

Neither Tesla nor GM sell batteries. Panasonic and LG do, and they're the ones making the actual batteries. However, you aren't likely to be buying millions of them, so you'll get nowhere with them. Search eBay for people who are taking Chevy Volt, Nissan Leaf, etc. EVs apart. We have several of the 6cell modules from Volt packs that will be for sale once we can ship them. (hazardous material, blah blah.) If you're local to RDU, come get 'em :-)

Comment Re:Charge? (Score 1) 382

Actually, buses DO clock a lot of miles/kilometers. Your car sees maybe a few dozen mi/km a day -- back and forth to work, shops, etc. A bus gets driven around a loop all day. Looking at the NCSU bus loops and schedules, the #8 (southeast loop) is about 5mi completed in ~30min. Buses run that loop 15.5hr per day. That's 150mi in a single day. For a single bus. As of right now (6:15pm) there are 26 buses running on 11 routes. They all used to stop at the gym -- at best for a few minutes, but that's not true anymore, so there's no single central point to charge them, other than the garage. Regen isn't magic. At best they get back a fraction of the power it takes to get it moving. Yes, a bus has a lot of space for batteries, but batteries are heavy. Batteries will account for far more than an engine and fuel tank. The power required to charge it is astronomical. Multiplied by several dozen buses, that's a massive load on the grid.

Comment Re:Uber? (Score 1) 641

Not so impossible at all... Any sane, sober person driving their boss's 90k$ (or more) super car would be driving like they're taking a driving test. There would be no stomping of any pedals. There would be no swerving into a tree. And she'd be paying attention to every f'ing spec of dirt. If there was a collision, it would be from the oncoming car hitting them at a dead stop.

Comment Re:Another breakthrough! News at 11! (Score 2) 218

Yes, the plastic tape is better, but they pack ever more data into the same space making "bit rot" much more of a problem. The best tape tech is DLT (and SDLT) -- relatively heavy tape with laser etched tracking on the back of the tape. DAT/AIT comes in second -- VCR technology with tracking data recorded along the bottom of the tape at the same time as data. Sony used to make some very strong ("DLC") tapes. In last place is LTO -- hard drive technology applied to a tape... tracking information is stored as data on the tape in a manner that cannot be replaced in the field. (It is absolutely trivial to ruin an LTO tape. I've had dozens destroyed by Iron Mountain.)

(NASA has had data tapes from the 60s and 70s "recovered" -- the drives to read them no longer exist, and they're in a format no one remembers.)

Comment Re:Big battery will put a stop to this (Score 1) 218

Actually, this sort of battery has been around for a while. They're big, heavy, and expensive. So, people tend to go in other directions. If I were buying a new PV off-grid system, a $30k 5ton room ("closet") full of lead is not the path I would take.

The home storage "market" is mostly a DIY world. Those people get whatever surplus battery technology they can -- i.e. cheap or even free.

Comment Re:Big battery will put a stop to this (Score 1) 218

(Note: LiFePO4 is a "LiPo" or "LiIo" battery. It is one of many chemistries. Arguably the safest of them...)

One US gal of gas holds 33.41kWh. At just over 6lbs per gal, that's ~5.5kWh/lb. A Chevy Volt battery -- the modules themselves, not the electronics and heavy casing -- is about 55Wh/lb. Not kWh but Wh. 100x less energy density. Cost-wise, gas is about $0.08/kWh (6.65c locally as of writing) vs. the Volt around $150/kWh (new, full module.)

Full car... it's a bit of a toss up. What you save in engine, comes back in batteries. Looking at race car numbers (because it's what I have), the EV race car (as much as it sucks) is more than twice as efficient. The Honda Civic (1.6L) eats a gal (33.41kWh) in 9-12 min. The EV, on roughly 12kWh (used batteries, actual capacity is not known), lasts about the same time [15min tops]. The gas car obviously can go a bit faster (100mph) because we're not babying a battery pack, but the EV is not "stupid slow" (60-70mph easy.)

Comment Re:Big battery will put a stop to this (Score 1) 218

Pb-acid still rules in UPS systems because they're dead simple. It doesn't take any complicated CV/CC sources, per cell voltage and temperature monitoring, or balancing equipment. You simply throw a trickle current (13.6-13.8v) on them and they'll sort themselves out. Very few systems use actual flooded batteries (even on data center scales); they use gel and AGM batteries.

Every laptop pack I've had fail (NiCd, NiMH, LiPo) have failed due to age. The things don't last forever! They have a finite number of charge cycles, and amount of power they can hold/provide diminishes over time. The batteries in my last laptop outlived the useful lifetime of the laptop (over 8 years.) My current laptop is ~5yo and the batteries are showing no signs of aging. My cell phone used to last 2 weeks on a charge; today, over a decade later, it'll last 2-3 days before dropping dead.

Comment Re:Recharge by Refill (Score 1) 218

Exactly. Think about the tried-and-true flooded lead-acid battery. If you simply drain and refill the acid after each discharge, the lead plates would completely disappear after a few cycles. (or they'd be so covered in sulfur they'd cease to conduct.) The electrolyte is not like gas in the tank, it isn't "consumed" as the source of power; it's more like a catalyst promoting ion exchange.

(but not exactly, as everything in the battery undergoes some measure of physical and chemical change.)

Comment Re:Another breakthrough! News at 11! (Score 3, Informative) 218

And have a real world lifetime of a few years. Archiving data is a tough job. Storing it in an amorphous, heat and light sensitive material is data suicide. Tape is still king here, and has decades of actual archival use to prove it's longevity. (yes, tape is subject to decay, but at levels that make optical discs look like play-dough.) I, personally, have tapes over 25 years old that are still perfectly readable. (and that's 15 years in a kitchen drawer, not the Svalbard seed vault.)

(* Note: choose your tape technology wisely. QIC-80 is known to not even survive a single full-pass write. LTO is all the rage, but it's exceedingly easy to permanently damage.)

Comment Re:Why do you need a contract to work? (Score 3, Insightful) 73

Wrongful termination is nearly impossible to prove in an at-will state. You can be fired for "any reason, including NO REASON". What does get employers in trouble is running the mouth about why they fired someone. (this is why no company will say why an employee is no longer there.)

Comment Nonsense (Score 1) 124

It's all bullshit. A lithium-metal battery is a SERIOUS. FIRE. HAZARD. And it cannot be fought with traditional firefighting equipment (i.e. WATER.) Go look at what goes in a Class D fire extinguisher, and then look at the cost. I'd like to see the zero weight, micro thin unubtainium shell he proposes to make the thing 100%, ABSOLUTELY puncture proof. We put Li-Ion batteries in tiny plastic bags.

The electrolyte is not flammable. Open up a pouch and stick a match to it. It. Does. Not. Burn. "Vent with flame" occurs because of the current flow resulting from an internal short -- in the Samsung case because of metal contaminates (and normal heat expansion crushing it within the confined case), in the case of a puncture because the anode and cathode are now touching. That's also why it's impossible to put out a Li-Ion battery fire: Current flow cannot be disrupted. All you can do is quench it until the charge is depleted. (which can take thousands of gallons of water)

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