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Yes, for people who can't charge off-street overnight. I think the electrifying London Fully Charged podcast episode said in London about a third of vehicles would still need to rely on petrol station model.

No, for people who can charge off-street. In fact, for those, using this should be discouraged for these owners and V2G need to be encouraged. Eg. much cheaper slow overnight recharge if vehicle is connected to V2G.

Because end of the day, you simply cannot sustainably (using renewables) recharge and achieve the same throughput as current petrol stations. To achieve higher renewable utilisation, we need more storage. EV's are perfect for storage when parked up during 90% of its lifetime.
 

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the electrifying London Fully Charged podcast episode said in London about a third of vehicles would still need to rely on petrol station model
So where are those cars parked when not being driven, and why could they not be charged there? (Not meaning to shoot @wyx087 - only electrifying London)
 

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So where are those cars parked when not being driven, and why could they not be charged there? (Not meaning to shoot @wyx087 - only electrifying London)
Exactly, somewhere in the UK every car is parked up for at least a few hours every day.

Charging should be targeted there, although I’m not against faster charging battery tech of course.
 

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It's the 21 Dec episode, "How London plans to electrify its streets". The figure was mentioned in the first half (I'm half way through it). Good points dk and Tooks.

No doubt 5min charging would be great for long distance travel.

But people's habit are hard to change, and if too many EV's rely on this would not be great for adoption of renewable energy. It will be more consumerism where each recharge station would need massive banks of batteries to handle the peak period throughput. This battery bank configuration should only be necessary on trunk roads. As much EV's as possible should be plugged in and serving as grid-helping-battery when stationary.
 

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An EV size battery "fully charged" in 5 minutes. Nope. Not gonna happen - the realities of charge tapering will see to that. You can't rapid charge any Lithium Ion battery at full speed to 100%. To 80% or so potentially theoretically possible but still very difficult on a large battery.

"StoreDot has already demonstrated its “extreme fast-charging” battery in phones, drones and scooters"

So only very small cells at the moment. The challenge with super fast rapid charging of EV's isn't just the cells themselves, it's trying to get rid of the excess heat to keep the cells cool during charging, the very large and heavy cables and connectors needed for the high power levels etc. Some of these things like cooling do not scale up well. Getting rid of a few watts of heat in a thin laptop battery is much easier than getting rid of 10's of kW of heat in an EV battery during super rapid charging.

I'm still sceptical.
 

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I'm sceptical on many fronts, as mentioned scaling this up to EV sized batteries must be a challenge. As above you'd need getting on for a megwatt to fully charge a 60/70kWh battery in 5 mins, the liquid cooled cables are chunky already!

You'd have to install them with battery storage (as per Braintree) and subsidise the cost with grid balancing etc I'd imagine, else perhaps it'd be £1+ per kWh. It would be fascinating/ scary to see the numbers for investment/ projected ROI etc for the Braintree hub.

I see they're talking about a tie up with BP and their 18k forecourts, but I'm not sure they're the right places anyhow - apart from their motorway services. If you're looking to mobilise the nation with EV's you'd surely be better off putting in lots and lots of cheap destination chargers. Workplaces/ gyms/ cinemas/ shopping centres/ car parks/ the street etc. You could probably do hundreds for the price of one "megacharger".

IMHO apart from a few outliers (who can go for a PHEV/ Tesla) EV's with a 60kWh-ish battery and 150kW MSA chargers is sufficient - 200 mile or so range with 20 mins for 10 - 80% charging (with lots of destination chargers at a fair price/ kWh for those without off road parking).

The game changer for me would be for Ecoatrocity to sell up and a decent network to take over with reliable, multiple chargers at their sites.
 

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No, because they are targeting a product to go on sale in 2025 which can achieve a 240kw charge rate (for five minutes). Tesla and Porsche can already do this (with the same caveats - this product needs to get the battery to 60C to achieve that rate, so the preconditioning may take longer than the charging).

Increases in energy density remain the best thing. More kwh in he same volume means smaller vehicles can be electrified with sensible ranges, and longer ranges reduce the need for frequent rapid charging, and also higher capacities can by nature accept higher charge rates (so the ten minute splash and dash will give you +200 miles on a car with a 150kwh battery, rather than the 35 miles it gave you on a 1st generation Leaf).
 
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That would only give 20 kWh of charge energy...Maybe just give 100 miles on a good day...
Agreed, but they'll be talking WLTP "miles", and we can all hope efficiency continues to improve, the Koreans are certainly still moving despite being very good already!
 

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Brilliant look into the future however.....:
"The batteries can be fully charged in five minutes but this would require much higher-powered chargers than used today. Using available charging infrastructure, StoreDot is aiming to deliver 100 miles of charge to a car battery in five minutes in 2025."

First someone will need to rework the whole existing charging network and secondly how the UK power grid will cope with this huge surge?
Can anyone with knowledge to shed a light please?
 

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Brilliant look into the future however.....:
"The batteries can be fully charged in five minutes but this would require much higher-powered chargers than used today. Using available charging infrastructure, StoreDot is aiming to deliver 100 miles of charge to a car battery in five minutes in 2025."

First someone will need to rework the whole existing charging network and secondly how the UK power grid will cope with this huge surge?
Can anyone with knowledge to shed a light please?
Could be achieved by front-loading some storage mechanism. Could be a battery array or some advanced super-capacitor that is fed with a continuous 250 kW current but can deliver spikes of 500 kW or maybe one mW for trucks. Instead of using cables, I think induction charger could be a better option to better cope with the heat and to avoid having to use unwieldy cables.

Battery tech needs to catch up though but it's a matter of time. Solid State or Lithium -Air batteries should allow for architectures with less internal resistance so less heat and faster charging. I believe the future is 350 kW charging and standard 85 kWh batteries in mid-size cars that can be 100% charged in <15 minutes and allow a real motorway range of 400 - 450 kilometers at legal speeds.
 

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Could be achieved by front-loading some storage mechanism. Could be a battery array or some advanced super-capacitor that is fed with a continuous 250 kW current but can deliver spikes of 500 kW or maybe one mW for trucks. Instead of using cables, I think induction charger could be a better option to better cope with the heat and to avoid having to use unwieldy cables.
Induction charging is much more inefficient and slower than a physical cable, they would need to improve induction charging before that became a viable 'quickcharge' option
 

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Yeah for me 350kw is a sweet spot - 20 minutes gets you 116kwh, good for at least another 300 miles at legal speeds, when the driver will definitely need to stop again for at least 20 minutes to use the bathroom/eat/rest/sleep!
 

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Faster charging allows batteries to stay small which helps mitigate the environmental issues and keeps costs down. Also smaller batteries weight less which helps efficiency.
Great news if this translates to a working car battery at some point!
 

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For the next generation of Formula E (Gen3), we are making small boost chargers (basically small batteries) to do around 600kW for a 30 second pitstop. It will only be around 10% ish of the capacity of the car's battery, but should be interesting to see where it goes.

As for boost batteries for chargers, you can remove some of the need for weight and space (within reason), so super caps could be more relevant due to their high cycling lifetime and peak load capacity. Just that their kWh/m3 is around 10-20 times worse than a lithium-based cell, so would need a fair amount of space.
 

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For the next generation of Formula E (Gen3), we are making small boost chargers (basically small batteries) to do around 600kW for a 30 second pitstop. It will only be around 10% ish of the capacity of the car's battery, but should be interesting to see where it goes.

As for boost batteries for chargers, you can remove some of the need for weight and space (within reason), so super caps could be more relevant due to their high cycling lifetime and peak load capacity. Just that their kWh/m3 is around 10-20 times worse than a lithium-based cell, so would need a fair amount of space.
I am intrigued by the 'we' in the first sentence. Would you say a bit more?
 
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