EV Charging

Well ...

Only if the car's onboard charger supports 3ph, if not it'll only use

not especially cheap

As I understand it, with DC chargers almost all of the power control stuff is in the charger, it's not just a rectifier!

They also cater for a range of voltages, many are 400VDC but very fast chargers will go up to 800V. Presumably only after negotiation with the car's electronics!

nib

That's where we came into this thread. The OP was querying 'how much for

You also need a beefier supply connection as even 3ph 100A won't get you to

Yes. It's like a giant scaled up version of charging LiPos for RC planes - you connect directly to the battery and the charger is outside the vehicle. If the battery is at 357.2V the charger has to output 357.3V or more in order to push current into the battery. The car tells the charger what voltage/current it wants and the SMPSU is outside (in a phone-box sized cabinet).

There's a whole load of safety stuff too - the process is being monitored all the time and if an anomaly is detected everything will shut down and disconnect.

Because generating 350kW DC in a single SMPSU is not terribly convenient or efficient, often those phone box cabinets contain multiple ~25kW modules which can be ganged together. Often the ganging can be switched based on occupancy - eg if one stall is occupied it may get 350kW, but if there's two stalls and the first car wants 100kW then that leaves 250kW free for the next car.

Indeed. Some can split their 800V pack in half to present it as a 400V pack to a 400V max charger.

The thing that I find most crazy about this is that DCFC on the CCS and NACS connectors only use two pins which carry both power and data (plus the earth pin from the AC side and the connector latching pin). Because they didn't want to add any signalling pins the communication is sent using power line transmission modulated over the super high current DC!

(ChaDeMo has separate canbus pins for data comms, but is being phased out)

Theo

When I were little, out next door neighbour worked 2 miles away.

Every winter without fail they'd need a jump start every 3 or 4 days.

Of course a hybrid solves all of that.

Actually, I think I'm wrong about that. It *is* doing power line transmission, but it's running it over the low voltage control pilot pin not the HVDC pins (ie it's the RF part of PLT without the 50Hz part). You can hack something up using a HomePlug adapter with the AC components bypassed:

Theo

We would need a more technical web page, to decide whether the scheme has any merit. Puff pieces like this, yes, we get to see a car charge once at the high level, but, will it do this continuously to the date on the warranty period ?

Paul

There are some diagrams here, of the various connectors on the cars.

For DC-mid charging (the extra two DC pins below those seven, not present), the N,L3 conductors are (+)DC and L1,L2 are (-)DC. 500V, 140A. So I suppose you could get to the 70kW level with DC charging, but I don't see how that plug is configured to reach 100kW.

The 500V, 200A option requires the two DC pins added to the bottom of the connector scheme.

CP PP Nine pins total for 100kW DC 500V 200A N PE L1 L3 L2 N,L3,+DC L1,L2,-DC six pins carry current

That's the kind of info as a buyer, I would be looking for. Confirmation of connector. Whether the connector involves any bodges. And so on.

If you happen to have a 500V 200A capable battery box sitting around, you could charge with that.

Note that cars have power quality analyzers, and they will "reject" any charging station where the power is "wobbling". For example, a car will not charge off a Honda Generator, unless the power is very very well regulated. The car measures the frequency, the voltage, for signs the charger is "on fire" or something. That is why they're checking, to detect a dirty or bad electrical connection, a chopped cable, a liquid cooled cable with a cooling failure, a burnt charging electronics on the charging pedestal. I want to point that out, in case you rig up a solution in the woods, and you're pissed to discover the car won't accept it.

You can do car-to-car charging. There are two cars in Quebec fitted with an output option, and they can roadside-charge a BEV enough, so the BEV can drive a few miles to a charging station. The car stops offering output like that, well before its own battery is flat. You can't exactly fill the other vehicle with the scheme. That was kind of an experiment, to see how practical car-to-car charging is, in emergencies. It's the equivalent of a 3 liter can of petrol :-) The car would return to the service center, and recharge, before answering the next call.

Paul

Europe uses the CCS Type 2 connector, so you get AC (1ph or 3ph) via the round part and DC via the oblong part underneath. There's no need to check anything.

Exceptions:

Some early cars especially Nissans have only the round AC part (possibly in the US Type 1 format). DC is via the ChaDeMo connector. There are adapters from CCS Type 2 for AC (cheap cable) and DC (active adaptor, newly available, still >£500)

Some small battery cars especially PHEVs don't do DC at all and just have the round AC part of Type 2.

Theo

What’s “best” about that? The savings from running an EV charged at home only increase with increased mileage.

Tim

(I was 60 miles a day but not every work day.)

nib

Well, don’t be offended but I’m not interested in your annual mileage. The question was for Jethro. What makes 20-40 miles a day (+ weekend longer runs) “best”?

Arguably the “best” mileage is the most you can do on home charging every day. In my case that could theoretically be 250 miles a day. The savings over running a diesel or petrol car would be enormous.

Tim

Substantial rather than enormous, and totally artificial. Compare the cost of fuel with fuel duty at 53p/litre (£2.41/gallon) and VAT at 20%, with the cost of electricity where the only tax is VAT at 5%.

Use your own figures if you don't agree: A reasonable EV will do about 4miles/kWh, so around 60kWh for 240 miles. With a standard electricity supply costing around 25p/kWh, the total would be around £15 to do the 240 miles. Let's say a petrol car will use around 5 gallons on the same run (around 50mpg) so about £30 at £6 a gallon. That's double the cost.

Now remove tax from the equation. £15 electricity is around £14.25 ex-VAT. £30 of petrol is £25 ex-VAT, and fuel duty on 5 gallons is about £12. So the petrol cost without tax is £13, and the EV cost without tax is £14 for the same distance. Which is cheaper?

With EV sales on the increase, and matters of finance heavily on her mind, our Rach will be working out how to make a grab on all those poorly-taxed kWh.

Assault on battery comes to mind... :-)))

Or a massive car road tax.

Is that a road tax for massive cars :-)

No, enormous. Neither of us can control the duty on our fuel. It is what it is. The saving running on electricity with an off peak tariff

Haven’t you heard of off peak tariffs? Now you’ll say that the increase in peak rate will significantly reduce the savings but even before we had a home battery, the greater the proportion of electricity that you use off peak with a medium to high mileage use EV massively outweighs the day time consumption.

So, do your sums again based on a 7p per kW cost.

See my comment above about our ability to control tax on fuel.

Maybe. When it happens, it happens. Until then, I’ve had five years of incredibly cheap motoring whilst all you naysayers are bleating “they’ll find a way to tax it!”.

Tim

Well, EV road tax is going up to £195. So what’s that, about three to four tanks of petrol/diesel? I’m not losing any sleep over it.

Tim

Let's all hope that your car never ran - or will run - out of juice in an inconvenient or dangerous spot.

There is a plan for a Kia Picanto EV but the news release said it was some time off. (Maybe at least 2 years.) No hint of a spec, except the comparison to Picanto.

Can a car that small hold a battery slab with 200 miles of capacity ? That would be the question in your case. And you need sufficient capacity, so that the trips you plan to make, could be made in winter, with the cabin area heat turned on.

A used car with sufficient range might exist, but the length of the vehicle is 30% longer than the Picanto. The garage door would have to stay open.

The cars with exceptional range specs, they are aerodynamic, but the wheel base is just huge on those things. It would only fit half way into your garage.

Kia Picanto 3595 mm length

# These have aerodynamic shaping, which improves their range. # The EQS is fairly temperature sensitive (cold weather range is 66% of warm weather range)

IONIC 6 4855 mm

Mercedes EQS450+ 5223 mm

# For comparison (i.e. closer to price target maybe)

The car makers know the Chinese are coming. And their small car offerings so far, are "press releases". Ford knew when it made the Mach E, that the vehicle had a mile of wire inside it, and they needed to redo the wiring and computer architecture, to reduce the amount of material (and assembly time). They have a plan for a cheaper car, where a lot of details have changed on how a car is made. There will be fewer employees needed on the line. The car is built in sections, then the sections bolted together,.

But as usual, most of the info available, does nobody any good. With cars "only a bird in the hand, with good reviews, matters". Not like a few BEVs, where the software wasn't really finished.

Paul