Prius Prime Plus in my hands

That deserves a big asterisk. I think the author was pointing out that charging to 100% is not good for the battery. L2 charging can charge to a lower SoC ;-)

 

Thanks. That makes more sense. I did get the impression that he was dealing with general principles and didn't assume the level of battery protection Toyota provides.

 

I've always considered this to be a complicated question, since the C rate, battery temperature, and SoC are in play. I try to avoid high SoC charging and parking on hot asphalt; and I definitely would not be inclined to use DC fast charging in cars without heat dissipation systems.

Incidentally, this is why you want your EVSE under a PV canopy ;-)

 

The other thing is that this paper was written in 2012 - the Leaf, i-MiEV, Volt, and Tesla Model S were all new, and the only EVs that had had significant mileage (and therefore time to degrade) were the old lead acid and NiMH EVs (EV-1, S-10 EV, RAV4 EV, and Ranger EV), and the Tesla Roadster.

Nowadays, batteries are bigger, and are using Li-ion chemistries, so we know that L2 isn't harmful (L3, OTOH, can be, especially if you hammer the battery with high temperatures). In addition, L1 is less efficient with modern EVs - if you've got 500 watts of load whenever the car's plugged in, you're getting less kWh in the battery per kWh input doing a slow charge than a fast one. And, preconditioning the cabin on L1 drains the battery, whereas L2 can get all preconditioning power from the grid.

That said, L1 is still a hell of a lot cheaper to deploy...

 

Interesting. Can you clarify whether L1 is always more expensive to deploy in all countries? I could easily have a 240v 16a supply installed from my electricity supply, which is 3 phase and already has plenty of capacity to supply our all electric heating. Or is it the Socket and outlet itself that is a lot more costly?

Also, what might be the relative cost of L2 vs L1 implementation once t he newly agreed wireless charging spec starts to be implemented?

 

My wife thinks those shields generally indicate cars owned by smokers.

 

I believe for L1, the company would also need to supply the EVSE because most L1 chargers are not meant to be portable.
For L2, the owner could be expected to carry their own EVSE.

 

If I understand correctly for mainland Europe anyway, people plug in their own 'smart' cables to the EVSE. In the US the public EVSE stations have cables pre-attached: usually J1772, sometimes Chademo; and perhaps in the future CCS since that that appears to be an emerging standard.

 

L1 is something that doesn't make sense in the context of European charging, because Europe doesn't have 120 volt service.

What it boils down to is, L1 is what you can get from a normal wall outlet in the US, which is rated at 120 volts, 15 amps, and EVSEs tend to be limited to 8 or 12 amps - for 960 to 1440 watts - in this application. (There's also 20 amp outlets, with up to 16 amp EVSE draw, for 1920 watts, that are still considered L1.) In Japan, L1 is done at 100 volts instead of 120 volts, with the same current limits (although 6 amps is more typical there, as I understand, meaning it's only 600 watts).

L2 charging in the US is basically anything done on 208 to 240 volts, up to 80 amps. (L2 in Japan would be the same limits, but 200 volts.) This is typically 3.3 kW all the way up to 19.2 kW. This usually requires an EVSE to be hard-wired in, or optionally plugged into a clothes dryer (240 volts at 30 amps) or RV (240 volts at 50 amps) outlet. This is where it gets costly. For comparison, a normal UK power outlet - 240 V, 13 A single-phase - would be enough to basically be considered level 2 charging in the US.

Then, L3 is DC fast charging using CHAdeMO, CCS, or Supercharger, at 25+ kW. That gets really costly.

In Europe, you have single-phase, three-phase, and DCFC charging. Even your single-phase charging is enough to be level 2 here in the US, and some of your three-phase reaches power levels that we can only reach with L3 (I'm thinking of 22 kW three-phase used by some vehicles like the Smart ED, or the 41 kW three-phase used by older Renault Zoes).

As I understand it, the EVSE usually offers a Mennekes socket, and you plug a Mennekes to Mennekes cable between the EVSE and the car. Alternately, if your car has a J1772 (and some do! The i-MiEV and relatives do, and I believe the BMW C-Evolution scooter of all things does), you get a Mennekes to J1772 cable instead.

Other way around. L1 is 120 volt, and the car comes with a portable L1 EVSE. L2 is 240 volt, and most of those are not meant to be portable.

 

A 3.3 kW EVSE is around $300 these days.
I paid $600 for a 9.6 kW EVSE of the highest quality I could identify.

 

The problem with L1 charging at work is having to bring your own charge cable with you instead of just using the one attached to an L2 charging box. We have L1 charging ar work and this is the major source of pain reported by users. But it sure is way cheap to install. We had conduit to the lot already for street lights so it was just pulling in some wire, three 20A breakers and three outdoor outlets. Way less than the cost of a single outdoor rated L2 EVSE (which can cost >$5k each) without installation.

 

However, $300 EVSEs aren't what's being sold to businesses for workplace charging, and are those even outdoor-rated at that price? (And modding a L1 EVSE for 240 volt isn't UL-rated, so that can't be used for workplace charging either.)

Something more like a ChargePoint CT4021 for around $7000, plus a subscription to the ChargePoint network, is what would be used there, with power sharing capability. (This also means that you get access control, to ensure that only employees are using it.) Or, for a cheaper option, a pair of Clipper Creek HCS-40s in a bundle set up for Share2 would around $2000 after you get the necessary accessories. (It has optional key-based access control, but that doesn't make much sense in a modern workplace.)

In any case, "having to bring your own charging cable with you" to an outlet isn't much of a problem, as every EV that I'm aware of comes with a L1 EVSE...

 

i used to charge L1 at work. just a non dedicated outlet on the side of the building. never had any problems. of course, pip only takes 3 hours, so i was charged for lunch, and could go out at lunch if desired, and recharge before going home.
it's an easy implement for employers, depending on the quantity of employees, and plug in vehicles.
L1 is rated for all weather charging, and keeping mine in the car was no burden.

 

Virtually all of the plug ins have that level of protection. BEVs aren't charging up to 100% SOC in general use; some, like Tesla, allow it as an option.

Level 2 charging can generate more heat in the battery, and that is the threat to battery life. With adequate cooling, and not completely topping the battery, this isn't a real issue for plug ins. Level 2 does have lower charging losses than Level 1, and it is the assumed charging for the EPA MPGe figures.

Just want to add that the SAE has redone the charging standard levels and dropped the Level 3 designation. It is now AC Level 1 and 2, and DC Level 1 and 2.

With it being likely that sidewalks and asphalt would need to be torn up, installation will also run higher for the business than for the homeowner.

Those using just Level 1 at home are likely to just leave the car supplied EVSE plugged in at their garage. Now they'll have to remember to bring it along or buy a second one. They're getting free fuel, I won't shed a tear.

If there is a sidewalk between the outlet and car, that raises a liability issue for the business if someone trips on your EVSE.

 

People either forget them or leave them home on purpose because they have them semi-permanently mounted in their garages.

 

No problem for Europeans perhaps, but I bet mainstream Americans would put up a stink.

If I'm wrong, I bet the car manufacturers could be easily persuaded to provide an UL certified 120/240v portable EVSE.

 

From MY 2014 the Nissan LEAF has no option other than to charge to 100% (usable.) The only work-around is to set start and end charging times. The standard explanation for the change is that Nissan wanted EPA to report on the window sticker the highest range possible, and a built-in option to charge to less than 100% would have forced Nissan to report a lower range.

<<shrug>>It seems like an unintended consequence of EPA rules, although Tesla obviously found a way around.

 

Why do you think so?
The European portable EVSE (Mode 2) although being for 220-240V single phase, weigh about the same and the "brick" is about the same size as the American Level 1 one.
BTW, the mode 2 EVSE supplied by Toyota in Europe (and this is true for the PiP and for the 2017 PHV) have a detachable 'pig-tail' with different plugs according to the country sold. This 'pig-tail' can be detached from the 'brick', so if you drive from the UK to France, as an example, and you want to charge from a household socket there, you can purchase the correct pig-tail' cord from Toyota and attach it to the 'brick' instead of your original.

Toyota's mode 2 devices (portable EVSE) in Europe are limited to 10A which gives about 3 hours to charge the 8.8 kWh size battery from 'empty' to 'full' @230V.

Attached are two pages from the 2017 PHV European manual.