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[gregj]

Talking high voltage, We might want to remember that, until coil on plug ignition systems, ICE cars and motorcycles had 40000V floating around under the bonnet in a big array( especially on old V8's.) with massive inductive transients.  Put your hand on a spark lead sometime ( if you are silly enough). Good design and engineering can get around most problems of voltage/current mentioned here.
If you want dangerous, remember that petrol ( gasoline) used in ICE vehicles , is a high vapour pressure explosive with carcinogenic goodness. We have designed around that, I suspect voltage/current electrics will no more difficult.

[Crissa]

Yeah, the distributor cables on our old Nova would arc into the firewall when we upgraded it.  It was a real pain ^-^;

Don's right, though, it's really hard to draw that through you.  Unless you're sticking yourself into the battery tabs.  And even that's just a burn.

My argument against high voltage electrics is more cost (number of cells, complexity) than anything.

-Crissa

[Doug S]

That's the bit that bothers me ... there are quite a lot of small niggly flaws in the current crop of leccy bikes that makes me worry about the overall reliability (and hence safety) of their designs.

Agreed. Workmanship and design have not been perfect on our bikes, historically, and they never will be PERFECT.

Keep in mind, though, that most if not all of the niggly little stuff has NOT involved the high voltage portions. My bike conked out once after I washed it especially zealously, and came back to life after it dried out thoroughly. Other people have had similar things happen. Clearly, these haven't involved the high-voltage stuff, or there would have been big sparks, audible pops, ozone smells and/or lots of smoke evident. Some low-voltage connector somewhere didn't keep all the water out and caused one or more signals to be interrupted. In some cases, where the bike didn't recover, the shop discovered pretty much the same thing -- bad contacts or a short circuit somewhere in the circuitry, not the high-voltage stuff. I don't know of any cases (of course there may be cases I don't know about) where water ingression caused a problem with the battery pack itself, the motor controller, or the motor.

The high-voltage stuff is pretty simple, and limited in scope: The battery and its BMS, the controller, the motor and the DC-DC converter. If you poke around on your bike, you'll find that all these interconnections are identified with orange cable wraps, well insulated and particular care has been taken to route them and protect them from water incursion. There just haven't been many (if any) problems with any of that.

(Looking at the Lightning Strike review tells another story, though, and it kinda makes my hair stand on end. Clearly they didn't spend anywhere near the time they needed to design and put together safe assemblies. Different story for a different day.)

[DonTom]

Talking high voltage, We might want to remember that, until coil on plug ignition systems, ICE cars and motorcycles had 40000V floating around under the bonnet in a big array( especially on old V8's.) with massive inductive transients.  Put your hand on a spark lead sometime ( if you are silly enough).

But that HV is low enough current so the voltage drops under the load of your body. Perhaps to well below 100 volts. And the higher that voltage, the lower the current, so you get even a larger drop. That's why we don't hear of people being killed by such--at least not often.  I have heard of many people being zapped by the HV in those old  cars, myself included. I have not heard of any serious problems from such (but I will not go as far as saying  it cannot happen).

With an EV that voltage will not drop at all. It's VERY high current as well as HV. If you have a 300 VDC battery you get a 300 VDC shock when you get across it. MUCH more dangerous than those older cars with 100 times the voltage.

 -Don-  Auburn, CA

[princec]

I did once reach down to try and find out why my old GT550 was running on 3 and grabbed the loose HT lead that was the root of the issue (I was sat on the bike with the engine running at the time). OUUUUUUUUCH. Jeez. It's really painful, not unlike an electric fence. Probably a good thing that my other hand was holding the rubber handlebar.

Cas

[NEW2elec]

This video is on an electric Mini which is all fine and good and watch it all if you'd like.  But near the end at the 10:40 mark James May describes the same issues I've been describing in this thread.  Like he says Electric is a great club but the batteries have to greatly improve for mass use.  Thanks for the back up Mr. May. 

https://www.youtube.com/watch?time_continue=29&v=Pgp0t2uxXfc&feature=emb_logo

[Crissa]

May is right, but he's wrong, too.

If we had charging everywhere, it wouldn't be an issue.  The vast minority of cars don't go on long no-stop drives.

-Crissa

[princec]

When you see the number of cars driving up the M1 from London to Newcastle in a day you'd maybe think again about that assessment... charging time is a massive issue that isn't actually going to get any better. It's not just the charging time - which is a PITA - we need approximately 100x as many chargers to meet the demand of a 100% electric fleet... and a number of sizeable power stations to power them. Hey ho. I'll be old bones by the time it's a real problem I imagine.

Cas

[Crissa]

There are 32.5 million passenger cars in the UK.  Each lane has at most optimum 2400 cars per hour.  That means even at it most full, with no accidents, a dual-lane segment of the M1 would take 141 days for every car to parade past.  But most of the cars you see are the same cars, over and over again.

And no, we wouldn't need a huge amount of new generation of electricity (although that would be a great problem to have).  For instance, per capita energy use has been stagnant in California for almost forty years.  And even if we were to run electric cars on bunker oil in power stations, we'd use less of it that we use now in gasoline.

We just need more charging points, period.  There should be nowhere to go that has anything that takes longer than twenty minutes that doesn't have 1/10 spots that are for charging.

There are millions of spaces with electricity right next to them which could do trickle charging.  The vast majority of time cars are not being used but sitting (about 96% of the time, given an average speed of 25mph over a average year of 10k miles).  If you have a modern car, it will have a fuel-economy reading, which will have the average speed in there.  Do the calculations yourself if you want to!

High-speed charging will never be the cheapest method; it takes more equipment, it can't be time-shifted, it requires greater access to the mains lines.  On the vehicle sit it requires a more complex battery.  No matter the battery tech, more cells for more voltage is more expensive.

-Crissa

[princec]

I think May was arguing that the Achilles heel of BEVs is the charging time, though, and I think he'd probably be right on the money with that observation. Waiting for hours and hours to do another 80-90 miles isn't going to win any customers. This is why Tesla are so far ahead of the other manufacturers (and you should see how staggeringly incompetently they have dropped the ball when they all got together recently to make their own fast charging network, with blackjack, and hookers, etc, etc).

Cas

[Crissa]

That's true.

But my point was that we need to install both.  You can't limp to a fast-charging station without them, and you can't avoid the expense of fast charging without them, either.

The lack of these in-between stations limits the adoption of cheaper, smaller EVs.

-Crissa

[princec]

Definitely. I wonder what the sweet spot for charging is... maybe 30kW DC?

Cas

[Crissa]

It's the wiring to parking that we need.  Not fancy charging.

-Crissa

[TheRan]

It's already there for a lot of places in the form of lighting, and with many places switching to LEDs they have the power to spare. I would assume that it's also 220 volts or there abouts so you could even do level 2 for 110v countries. Imagine if they even did it with street lighting (every single lamp post would be a bit excessive, perhaps even 10 posts or something), you'd be able to charge pretty much any place you'd park up.

[princec]

This idea about lampposts keeps cropping up, but the actual physical location of the lampposts is just the tip of the iceberg. It's got to be safe enough in all weather, it'll need a payment infrastructure somehow setting up, it'll need a way to automatically flag repairs (or they'll all be broken and fucked within a month, as we see already from all the other chargers that are already out there), but most of all they'll need enough juice to power the whole road with at least 7kW... hmm. I mean it's a great idea, but just a lot more complex and expensive than it seems at a casual glance.

Cas