My Motorcycle Cycles (NBZ5)

See also: Charging, Part STFU I, II and III

An easy quip for haters is “you’ll have to replace the battery,” at a significant cost.  Lie- No, I won’t.

I’ll just say it: Zero claims a battery life of 3,000 charge cycles before falling to 80% capacity.  Depending on pack size ordered and city vs. highway use, this would mean 120,000 to 300,000 miles– essentially, the life of the vehicle.  The number of people who will ride a motorcycle over 120,000 miles is low; the number over 200,000 might as well be ignored.  This tracks well with Toyota and Ford numbers and experience, which I’ll get into.

Starting with the Toyota hybrid in 1998, large automotive packs have gathered plenty of experience.  This includes taxis, which includes desert and Canadian taxis.  Mass failure of taxis and batteries has not occurred; one Canadian cab is still going after 400,000 kilometers.  Notice I said “mass failure.”  Even when lifetimes are “reached,” it has been found that only a few bad cells in the pack need replacing, at marginal not system cost.  And that’s to the arbitrary 80% capacity; a hybrid can run fine with a 70% battery pack.  But even this is assuming you’d take the bill; battery packs are required to be warrantied to eight years/100,000 miles in most states, and 10 years/150,000 mi in California-compliant states.  In other words, don’t worry about it.  The manufacturers don’t even like having separate state-by-state inventory, so all vehicles effectively get the 10/150,000 pack design (“homologation”).

Now, most of this experience is with Nickel-Metal Hydride (NiMH) cell chemistries.  Lithium chemistries have only been sold for highway use for a few years, though of course both smaller devices and spacecraft have been using them longer.  According to Ford, lithium will actually beat NiMH.  So far, lab and field tests have lithiums tracking above NiMHs in lifetime capacity and longevity.  This jibes with Zero’s claim.

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The obvious exception, of course, is the Nissan Leaf issue.  A fraction of owners in Arizona and inland California reported fast degradation and decreased capacity, and got compensation.  In this case, Nissan cheaped out, and used an air-cooling system for the Leaf battery pack.  Chevy, Ford, etc. are offering liquid cooling for their EVs, and have not seen this problem.  When under high current, a battery generates heat; if it’s already hot out, the pack can exceed its design limit.  All vendors anticipated this, but Nissan thought it could get away with just fans.  This didn’t pan out where the air temperature itself can be over the design limit.  Note that Leaf owners in temperate regions have not had this issue.

In the case of my motorcycle, the pack size is so small and exposed, no real heat buildup occurs.  At 6 kWh, it’s a fraction of the size of the Leaf or Volt.  In particular, no ‘innards’ are buried deep enough, in the pack or in the vehicle overall, to retain high temperatures.  Other Zero owners have measured their pack temperatures after hard riding on hot days, and found nothing of concern.  Even this is assuming the vehicle computer and its temperature sensors fail to protect the pack.  The manual warns that the computer will dial you back, and eventually shut you down, for thermal excursion.  But I’ve only heard of one or two owners who have seen this; it’s never happened to me at all.

I anticipate that my battery will be economically obsolete (rendered so by some other cell) before it becomes functionally degraded.  That is, I don’t worry about it.

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Range is more than Zero (or CHAAAAARGE!) (NBZ4)

See also: Nothing But Zero 1 and 2

Okay, so I’ve described how I charge my electric motorcycle– I plug it into a standard wall socket.  Next question (and the one I get a lot): haw far can you go, on that charge?  Short answer: It depends.

The manufacturer’s EPA range claims are for the small and large battery packs.  On the standard, ZF6 battery, Zero claims 76 miles city, 43 highway for 2012.  The large, ZF9 pack then gets 114 miles city, 63 miles highway.  Now, a good engineer (as well as marketers and dealers) would then ask the next logical question:  ‘Where do these claims come from?  Under what conditions?’  Basically, ‘why?’

The city figure is easy enough: the EPA has an UDDS cycle (urban dynamometer driving schedule), which lays out the test parameters.  A certain number of stops, a certain number of accelerations, to a certain speed, etc.  So far, so good.  The highway number, however, does not list a driving cycle.  Zero considers this “cycle” to consist of half steady-state operation (i. e., freeway cruising), plus half surface streets, to get to and from the highway ramps.  In other words, a mixed cycle.  They got dinged for it, and for 2013 list separate city, highway-only, and mixed range numbers.

Next, next, next question: what’s been my experience, riding a production vehicle on real-world roads?  Zero may have equivocated, but they didn’t lie.  Again, the test cycles can be replicated by independent testers, and Zero didn’t particularly feel like getting caught on this.  In urban riding, a charge basically lasts forever.  You’ll run out of butt strength and bladder size long before you run out of battery.  I have never had an issue with range in-town; based on my commute (6 miles each way) I could and do skip a night of charging every now and then.  If I make no side trips, I could commute most of a week without recharging.  Even that’s not an issue, since my side trips are mostly stores and restaurants along the way to work.  Not much more than a mile extra, three at most.

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Okay, what about highway riding?  Again, Zero didn’t come up with their number from thin air.  Highway riding returns much lower range, unlike cages in general, and gasser cages in particular.  The difference is drag.  Motorcycles may look cool in a general and social sense, but from an engineering stance, they’re aerodynamically filthy.  An exposed rider, with their arms and torso sticking up, will never be clean.  Aerodynamic “sleekness” is measured by a ‘coefficient of drag’ value (Cd).  Where a well-designed car might have a Cd=0.30 or even less, a motorcycle with rider is about 0.7.  That’s as aerodynamic as a pickup truck, or as un-aerodynamic, I should say.

So overall, I have found that highway range is… variable.  I’ve tucked extra low; I’ve drafted behind trucks.  More on that later…

Girdling This Plan

Sadly, Terry Hershner did not ride across America on battery power alone.  Planned charging stops were thwarted, when the privately-owned chargers turned out to be behind locked gates:

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These charging locations, all owned by Oncor, were the only ones listed between mid-Texas and mid-Arizona.

I’ve encountered this issue before.  Back when I had a cage, I looked into converting it to propane as a clean, domestic, less-expensive fuel.  The conversion costs would be low, and supposedly propane has a lot of dealer locations.  However, many of these propane locations are actually for private vehicle fleets (e.g., company trucks), and you can’t just show up and start pumping.  Other locations are simply RV suppliers, who sell 5-gallon bottles of propane, not actual bulk fluid like gas or diesel.

Haven’t had an issue with locked electrical equipment yet.  Then again, I’m not in that high desert.

Electric Hel…icopter

Did I say electric helicopters?  Yes, I did.

A funny thing happened on the way to the future- new technologies manifest themselves in unexpected applications.  Manned electric helicopters have appeared from US, French, and German teams years ago.  They’re not ready for sale yet, of course.  These are proof-of-concept builds, which need much refinement before they’re actually desirable, let alone saleable.  But that’s not my point.  I don’t actually want to buy one, but the concept has, in the engineering sense, been proven.

Electric helicopters had been considered unthinkable.  Unlike a car or even a conventional airplane, a helicopter supports itself on its engine thrust.  (A plane pulls itself forward; the wings hold it up by exploiting forward speed.)  A helicopter that could lift itself with batteries and motors seemed ridiculous, since they were heavy.  WERE.

Now, lithium batteries and high-field-density coils and magnets and compact switchgear mean manned vertical flight is possible without internal combustion.  That’s vertical flight, now; planes and cars and 2-wheelers are easier issues.  In fact, Stan Ovshinski, the “father” of the Nickel-hydride battery chemistry, felt before he died that electric cars could already be practical on NiMH batteries.  NiMHs are older, cheaper, and more rugged than lithiums, but heavier.  For non-powered-lift vehicles, traveling on a nice road, he may be right.  The Toyota RAV4 EV from 1997 had a NiMH pack, and ran fine.  Many are still on the road today, with range still acceptable by today’s standards.  The modern, lithium redesign is then even better.

Charging, Internal Version (Charge 10)

Where was I… oh, attempts to dramatically speed battery charging.  Our best shot may not be due to better external chargers, but better cell chemistries.

-A Korean research group has formed batteries with a micro-mesh inside.  At the country’s Ulsan national laboratory, a blend containing carbon then forms a cell with a network of graphite conductors throughout.  The conductor grid allows charge to enter and permeate the cell at dramatically higher speeds.

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If the lab results make it to the consumer, batteries might charge over 2 orders of magnitude faster than today.  Overnight charging would then fall to 5 minutes or so… if you have humongous voltages and currents available to take full advantage.  More likely, engineers and buyers would settle for home charge times of 20-60 minutes, and instead use voltages and currents only modestly higher than what we plug today.  Only roadside charging would exploit brutal amperage at many hundreds of volts.

But let’s suppose even that’s a stretch.  Let’s say the lab results are optimistic, and actual products will only improve by a factor of 5.  An overnight charge still falls to 90 min, not even overnight anymore.  You could come home from work, fill up during a meal and a shower, and still go out on the town with a full battery.  Or you could run errands all Saturday, come home for a real lunch or dinner, then keep right on running (regardless of what public charging is or is not installed).

-A team at Rice University has placed the lithium in a matrix of crushed silicon instead of carbon/graphite.  Crushed silicon forms tiny, rough particles.  Lithium ions could only penetrate so far into solid silicon without destroying it; crushing forms “sponges” for lithium, and it’s cheap, too.  You might make these sponges from the waste from computer chips or solar cells.

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The net effect is cheap, dense lithium cells.  Batteries would go much farther than today, without much more size, weight, or cost.  The best part?  I don’t see this as incompatible with higher conductivities and faster charging, at least, not as a first-order effect.

-In addition, batteries may be charged faster by rebuilding… nothing at all, except software builds.  A research group at the University of California-San Diego has devised new charging algorithms, that more closely model what’s going on inside a given cell.  With a better handle on charging, you can pour on the juice without damage.  One possible claim is 15-minute charges, though it’s not clear what their conditions for this are.  Also, a better handle on charging means faster discharging too (i.e., more power) or smaller battery packs (lower purchase cost) with less damage (lower lifetime costs).  In other words, a win-win-win situation.

Overall, it appears that one way or another, charge times will fall to some fraction of today’s.  It’s just a matter of what fraction, and in what way.  Lots of things besides EVs use batteries- laptops and phones, portable drills and other tools, and plenty of infantry gear.  Thus, researchers are making the future happen whether you support “those damned cars” or not.  ‘Lots of things’ also includes motorcycles, military vehicles, and helicopters…

Girdling This Land, High and Low

How did I not post about this sooner… two attempts are being made to cross the continent in EVs.

Terry Hershner, of Off The Grid note, is crossing the USA on his “Zero motorcycle.”  The release party of the 2013 Zero lineup is later this month in California, and Terry wants to get there solely by electric motorcycle from his sustainable-base in Orlando, FL.  Notice I put his motorcycle in quotes; by this point, it’s hardly recognizable as a Zero:  The frame has been lengthened, both fore and aft.  The brakes are upgraded.  The power controller is the next size up, and significantly boosts the boost.  The new chargers (yes, plural) now allow up to 8 kilowatts of total juice.  Charge time is now under two hours at a charging point that can put out that much; some will only do 6 to 7 kW.  For the trip, he’s added a custom, secondary battery pack to increase range.  Specifically, it’s for the stretch between the Texas megalopolis, through the desert.

Given his schedule, Terry will basically be catching naps in those two-hour stops.  In places with no accessible power greater than a wall plug, he’ll have the luxury of crashing in a motel room with the extension cord next to him.  Seriously, he’ll be living off fast food where he can, and energy shakes where he can’t.  Let’s hope he doesn’t have a boo-boo from sleep deprivation.

Right now, Terry’s in the middle of Texas.  Happy trails… er, Interstates!  Oh, and don’t think it’s cheating to go from Florida to Southern California, instead of, say, New York to Seattle.  Terry’s starting from Orlando, then making it a Miami-to-California crossing.  Check his status at http://chelsealiggatt.com/blog/hershner.

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The other cross-country trip is across the other wide country in North America.  Kent Rathwell and Christopher Misch, executives at Sun Country Highway, are driving from Newfoundland to British Columbia in a Tesla.  Sun Country Highway is installing charging facilities across Canada, and are now putting their butts on the line (literally and figuratively) to demonstrate its effectiveness. The exact route isn’t being made public, but since the SCH charge facilities are now being activated for public use, you can do the homework and figure it out.

Their Tesla Roadster is capable of longer ranges than most EVs, but then again Canada is a long country.  It helps that the Sun Country charging points can put out 14-21 kilowatts at 240V; Teslas are among the few EVs that can take that much amperage at Level 2.  Of course, it also helps that they’re not facing the sort of schedule pressure Terry’s under.

Other cross-country EV trips include Geoffrey Kinsey’s trip this past June (roadsteracrossamerica.blogspot.com– and this one’s LA to New England), and Steve and Jesse’s in September (teslamodelsxc.wordpress.com).  Bonus: after the successful trip, Car and Driver wank Csaba Csere wrote that electrics “won’t work on an interstate”.  Steve and Jesse then replied, “Csaba, “won’t work on an interstate”? Plz explain. We drove from SF to DC in 8 days on interstates, and it worked just fine!”