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If it develops as they expect then this will be a game changer but according to the article not a reality just yet. Hopeful idea though
 

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The charging current would be phenomenal, and would either mean very heavy (thick) cables, or very high voltages to the charge points.
Kw (charge) is basically a matter of volts x amps. Yes, I know about power factors, but I said 'basically'.
The infrastructure just isn't there and would be phenomenally expensive to install, run and especially, to supply.
There would also be high heat transfer, which batteries just don't like.
 

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The charging current would be phenomenal, and would either mean very heavy (thick) cables, or very high voltages to the charge points.
Kw (charge) is basically a matter of volts x amps. Yes, I know about power factors, but I said 'basically'.
The infrastructure just isn't there and would be phenomenally expensive to install, run and especially, to supply.
There would also be high heat transfer, which batteries just don't like.
Agree that votlage or curent will neeed to be high and perhaps the new technology produces less by-product heat.

Power factor is entirely irrelevant to DC systems
 

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The charging current would be phenomenal, and would either mean very heavy (thick) cables, or very high voltages to the charge points.
The report that I heard mentioned that the difficulty would be the need for (far) higher charging voltages and providing the infrastructure to deliver that.

1000 volts is often used for 'Hotel' services (lighting, aircon, at seat power) on trains but the cables and connectors between coaches and the insulation required are pretty significant. 1000 volts at 60 amps would still take an hour to charge a typical battery (60 kW)

To get 60 kw across in 5 mins you would need a significantly higher voltage if the cables / current are to be manageable. Maybe looking at 10,000 + volts! Some serious safety issues to contend with. (I accept that in real life you would probably not be charging a completely flat battery)

If a motorway charging station with say 10 charge points were installed it would need a grid substation building on the site.

It certainly will make EV more attractive but I suspect that initial use will be talking about longer charge periods like 30 mins.
 

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Power factor is entirely irrelevant to DC systems
Correct, but an AC system will be powering it, and I did say 'basically'. If you want to get technical, I'm a retired Electrical Engineer, but I don't see any need to start going overboard with technical aspects of power distribution when we're only really interested in the end connections and what they power.
 

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Correct, but an AC system will be powering it, and I did say 'basically'. If you want to get technical, I'm a retired Electrical Engineer, but I don't see any need to start going overboard with technical aspects of power distribution when we're only really interested in the end connections and what they power.
Well it was you who introduced power factor to the thread. Any charger design supplying a unity pf load will present very close to unity power factor to the AC supply. Such a charger will almost certainly be a primary switched power supply so no big and heavy transformer.
 

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Please read my post again. You seem to have missed the point. I did say 'basically'. But as you started the subject, here's more.
Regarding a primary switched power supply of what will be high voltage input to get a high current output for superfast charging, the difference in primary and secondary voltage difference will be via a transformer as that's how inverters work, whether you go from dc-ac in pv generation, or ac-dc in 'smart' battery charging using chopping circuitry to limit current as the battery voltage approaches 'full'.
Also remember that transformer power factors change as the load out goes up and down, so on high current outputs that fall as the battery charges, active power factor correction would have to be built to the controls or the companies that run the charges wouldn't be making as much money, which, after all is what their aim is.
The power factor of a transformer is never unity, as a transformer has to magnetise the core (kvar) to make it work and in any case some of the wasted energy is also heat.
NOTHING is 100% efficient, although a transformer (defined as a machine that makes one kind of energy do something else - electricity - magnetism - electricity) is as near as we get.
 

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Please read my post again. You seem to have missed the point. I did say 'basically'. But as you started the subject, here's more.
Regarding a primary switched power supply of what will be high voltage input to get a high current output for superfast charging, the difference in primary and secondary voltage difference will be via a transformer as that's how inverters work, whether you go from dc-ac in pv generation, or ac-dc in 'smart' battery charging using chopping circuitry to limit current as the battery voltage approaches 'full'.
Also remember that transformer power factors change as the load out goes up and down, so on high current outputs that fall as the battery charges, active power factor correction would have to be built to the controls or the companies that run the charges wouldn't be making as much money, which, after all is what their aim is.
The power factor of a transformer is never unity, as a transformer has to magnetise the core (kvar) to make it work and in any case some of the wasted energy is also heat.
NOTHING is 100% efficient, although a transformer (defined as a machine that makes one kind of energy do something else - electricity - magnetism - electricity) is as near as we get.
No! You are describing an inverter power supply (which I used to design at one point in my career)

True primary switching power supplies use no transformer, they chop short duration pulses directly from the supply to achieve an average DC of the desired value. In one of my roles I used to repair (relatively small) DC DC primary switchers but AC DC is entirely he same principle. This eliminates the need for a large and heavy magnetic core capable of handling the power without saturating. Think of the size of a transformer to handle even 60kVA! A primary switcher may have small inductance/capacitance to reduce switching interference on the supply side but this will be working at a high frequency so these are small components and contribute minimally to power factor.
 

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I think we'll agree to disagree on this one.
Part of my working experience was to commission and optimise systems like that.
 

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Turnup, AlanH you seem to have gone OFF topic. The question was are batteries capable of 5 minute charging going to be a game changer for the future of EVs
 

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Turnup, AlanH you seem to have gone OFF topic. The question was are batteries capable of 5 minute charging going to be a game changer for the future of EVs
5 minute charging will indeed be a game changer - but such a battery is of less benefit if you can't charge it.

Transferring 60 kWh, over manageable cables and connectors, in under 6 mins, will be a significant challenge to the electrical engineers. I doubt if any current domestic electrical installation, or residential street power reticulation systems, could handle it. Certainly not if more than one house on the street supply wants to do it at the same time.

That's not to say that development should not continue.

(If my thoughts are correct my current house supply (60 Amps) can only deliver 1.150 kWh in 5 mins. - a long way short of 60 kWh of the average EV battery)
 

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Horses mouth.
the electric vehicle has a pack comprising of hundreds of EV Flash Battery cells that can store enough energy for up to 300 miles (480 km) range on a 5-minute charge.
 

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Somebody mentioned AC DC (Turnup) and now I'm staying up late listening to ACDC live at the River Plate (utube). Going to be a long night.... Thunderstruck!
 
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I realise that the makers of fuel cells and manufacturers of cars designed to run on hydrogen don't want to talk about the dangers of hydrogen in the event of a serious car crash.

That said, it does concern me that hydrogen fuel might not be be contained as well in a serious collision as current fuels. I know petrol is lethal in the way it explodes if triggered by a spark in the event of a car crash, diesel too although a little more difficult to ignite. Are my fears unfounded or will we inevitably see more major conflagrations on our roads if hydrogen-powered vehicles become mainstream?

I know that Tesla have had to liaise with some fire services in the USA because of the previously unknown dangers of explosive fire from the full-floor battery packs. Evidently, serious car crashes involving Tesla models have presented extremely difficult containment measures for firefighters.

If electric car fires are difficult for the emergency services to deal with, will hydrogen present even greater problems?
 

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I watched a very interesting documentary a few years ago about the Hindenburg airship disaster. Apparently hydrogen does not explode, just burns, and because it is lighter than air it burns upwards not outwards. The moral is that the death and injury rate of the Hindenburg accident could have been a great deal higher. No real point in this post except I found it interesting.... :giggle:
 

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@phil866 - there is a point as you raise one of the misconceptions of hydrogen, as a fuel, being explosive. In many ways a tank of hydrogen is safer than a tank of petrol as a damaged petrol tank will leak fluid which will spread around the ground and potentially, explosively, catch fire which will be difficult to extinguish. In the Hindenburg disaster it was found that the flammability of the doped canvas and timber, making up the airship body, spread the fire to the other hydrogen storage bags. Doped canvas is one step away from gun cotton!
 

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And I've just read that Jaguar Land Rover will be all-electric by 2025 and will launch electric models of its entire Jaguar and Land Rover line-up by 2030. How that last bit equates to being 'all electric' I've not worked out yet..... However of more interest I also read 'It will also invest in hydrogen fuel technology.' So JLR see a future (and profit) in Hydrogen at least.
 
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