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5 minute full recharge?

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So the question is now which will come first that battery or a charger in mid wales capable of making good use of it.
The company is aiming at 2025 for the battery so my money is on that :D
Blimey, had never seen that before. Looked at the map and thought there is plenty of chargers there. Disabled 50kW or below on the toggle and everything disappears.
 
There are barely any petrol stations in mid wales either, is the area really hard done by with EV charging ?

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The cells pictured on that website look very similar to those inside a Nissan Leaf battery pack. Something about this doesn't ring true to me, not least some of the language used to describe what would be, if true, pretty revolutionary battery technology.
 
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Can’t say I feel the need for a battery that charges any quicker than the one I have now. Increasing battery longevity is a more laudable aim.
There does need to be some solution to create more capacity, faster charging is better than more charging. This is the one area of the electrification of the UK that I've struggled to picture. I reckon that there are typically 50-100 cars stopped at most motorway services, it doesn't seem credible that there would be 100 150kW chargers so everyone could enjoy a quick coffee while their car charges like we Tesla Owners do today.
 
There does need to be some solution to create more capacity, faster charging is better than more charging. This is the one area of the electrification of the UK that I've struggled to picture. I reckon that there are typically 50-100 cars stopped at most motorway services, it doesn't seem credible that there would be 100 150kW chargers so everyone could enjoy a quick coffee while their car charges like we Tesla Owners do today.

100 is easily credible. 24 are being installed at the new services in Rugby. The biggest Tesla installation in Europe is 42 superchargers at Rygge in Norway. I’ve seen planning proposals for new services on the M25 that include rapids on half the parking spaces. If I was planning motorway services I’d be wanting people to stay 15-20 minutes, not 5.
 
Just been doing some quick and dirty sums. The cells that are currently fitted to my (DIY converted) electric motorcycle are pretty old now, they were made in 2012. Looking at their spec, they have a maximum charge rate of 10C. I would expect newer cells to be capable of higher rates than this. Anyway, assuming that my Tesla was fitted with these 2012 technology cells, and that it had a nominal battery pack capacity of 77 kWh, then the maximum charge rate would be 770 kW, very roughly a time to charge from 10% to 90% of about 4.8 minutes.

So, I strongly suspect that there's nothing much "new" about these cells at all. The issue with very rapid charging almost certainly isn't related to the cells used in any battery pack, but the issues surrounding charge provision and management. The maximum current that can be supplied via a CCS connector is 200A for non-liquid cooled cables, or 500 A with liquid cooling. To get a charge power of around 700 kW means significant vehicle and infrastructure changes.

Right now the car with the highest theoretical charging capability (not actually implemented, though), is the Porsche Taycan, as it has a battery voltage that's roughly double that used by practically everyone else, and this allows faster charging whilst staying within the CCS connector maximum current limit. Tesla battery packs are ~ 400 VDC, the Taycan battery pack is ~ 800 VDC. 500 A at 800 VDC would allow charging at up to 400 kW, whereas the 500 A CCS connector limit restricts even the highest voltage Tesla model to 200 kW (yes, superchargers are capable of delivering more than this, but the CCS connector is officially limited to 500 A, even with liquid cooled cables).
 
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It seems to me that there are peak speeds frequently quoted and then someone extrapolates that based on the assumption that the car will continue charging at the peak rate for the duration of the charge. We all know that peak charge rates are not the whole story. The charging curve means that high rates are not sustained for very long. Without increasing the present quoted charging speeds there is huge capacity for improvement in the speed of charging if the rate can be sustained over a longer period. 150kW would be tremendous if that was the rate from 0% to 100% of battery capacity!
 
Just been doing some quick and dirty sums. The cells that are currently fitted to my (DIY converted) electric motorcycle are pretty old now, they were made in 2012. Looking at their spec, they have a maximum charge rate of 10C.

One issue is that as soon as cells are connected to increase voltage, internal resistance of the stack increases. For example if 10 cells are collected to get 10 times the voltage, all the charging power for one cell has to heat up the other 9 cells.
 
The cells pictured on that website look very similar to those inside a Nissan Leaf battery pack. Something about this doesn't ring true to me, not least some of the language used to describe what would be, if true, pretty revolutionary battery technology.

It feels to me like a press release with no substance. Their site talks about 5 minutes but never about capacity, charge rate, etc. But that number is useless on its own.. I can add about 20kw in 5 minutes in a v3 charger.. did I charge in 5 minutes?
 
One issue is that as soon as cells are connected to increase voltage, internal resistance of the stack increases. For example if 10 cells are collected to get 10 times the voltage, all the charging power for one cell has to heat up the other 9 cells.

Charging doesn't work like that, as when the BMS detects one cell group has reached cut off, that cell group gets shunted, in order to prevent charge current flowing through the cells and damaging them from over-charge. This only happens at modest charge rates, when rapid charging the BMS just signals the charger to shut down if this happens, as the cell group shunts can only handle a modest bypass current.

Internal resistance isn't a major issue when charging. Right now I'm just putting together a new battery pack to replace the one in my old UPS, using the best value cells I could find. These have a 20C rating, and each 5 Ah cell has an internal resistance of about 2mΩ (measured). I believe that the cells Tesla use are somewhat better than this, so each 46 cell group within a Model 3 pack, for example, would have an internal resistance of probably less than 0.5µΩ. If charging at the maximum current that a CCS connector can take, 500 A, then the heat generated in each 46 parallel cell group during charging would only be about 0.125 W (from I²R, 500² . 0.5µΩ = 0.125 W).

The CCS connector and lead is going to present more of a heat problem, as their resistance will be higher than any cell group in the battery pack, by a fairly hefty margin. For example, a 4m long CCS cable, rated at 500 A, has a cable DC resistance of roughly 1.5mΩ, so a heat loss when charging at 500 A of around 375 W. The connector probably adds another 50 W to 100 W or so to this loss, from its contact resistance..
 
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Indeed, but in the future we have to see this as charging where you park, whether that is on your driveway, on your street, at work, at leisure or doing the shopping. Crack that and there’s no need for ever bigger batteries or ever faster charging.

On road side charging for all possible parking spaces will not come until most of the public believe they will benifit from it. EVs have to become common, eg more then 25% of all cars first.