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Discussion Starter #1
This development could swing the fight over a world standard back to Chad instead of CCS.

 

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Is there a practical limit on what charge rate makes sense?

The maximum charge rate for most conventional chemistries is around 3C, in practice you really want 1C if you want the battery to last.

If you had a battery that can take 500kW at 1C then it's 500kWh ... would you really ever need to charge that on a route!?!?

This probably applies to long distance trucks, but is it relevant for cars. Probably the limit of charge-relevance is already with us with Tesla's rates and Porsche's 800V systems.
 

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I suspect that the 'game changer' here is the proposed two way transfer of power ability. The plan is to enable homes to take advantage of time shifting cheap power to run houses without having to also invest in expensive battery banks. CCS is scrambling to emulate that facility - and has been trying to do that for years without a breakthrough.
 

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This is one of the ways they will get charging into the transport sector, how many transport vehicles as a % sit idle for a long time overnight so they could "trickle" charge?

HGV's for example dont have many that will stop for such periods, same with larger courier vans and we know they are going to have to go with large packs to get decent ranges.

Buses could be an exception but if you have a depot with say 100buses parked up and they are all charging at 7kw over night then your at 700kw already. thats a hell of a lot of juice to be sucking from the grid in one location, where as say, if the bus had some 15minute stops along its route at 200kw chargers then it could top up easily thru the day as thats near 50kw pulled down, or at 500kw thats 125kwh pushed into a battery.

Those power levels would allow a vehicle as well to have a much smaller battery, thus less weight and more cargo carrying ability.

Look at the Tesla Semi, when it charges it has to tie up 5 Superchagers :D that in theory is over 500kw
 

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Buses could be an exception but if you have a depot with say 100buses parked up and they are all charging at 7kw over night then your at 700kw already.
A bus depot would/should have its own 11kV feeder which could comfortably supply 10MW or more.
That would probably be simpler and cheaper than trying to fit multiple smaller chargers along the route, each of which would probably be connected to the local 415V system, which then might need beefing up.

Those power levels would allow a vehicle as well to have a much smaller battery, thus less weight and more cargo carrying ability.
That is a good reason to consider on route charging.
 

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I think you need to achieve over 200 miles per hour charging rate, at the very least, for general population acceptance of electric vehicles. GIven that some vehicles are ridiculously heavy (ironically in some part due to the vast amount of heavy batteries) and not so efficient I think we do need to see at least 200kw becoming the norm for fast chargers at motorway junctions and by main routes everywhere.

The shape of the socket on the other hand doesn't matter one jot, it's entirely down to the amount of current required to be carried and the smarts in the communication protocol. In fact it would be better for all concerned if they all agreed ONE standard socket and protocol and stopped this messing about.
 

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. In fact it would be better for all concerned if they all agreed ONE standard socket and protocol and stopped this messing about.
Unfortunately it's now just too late for that, and more unfortunately, we're stuck with CCS, which, at least protocol-wise, is a truly terrible standard.
It's way, way too complex for the task, leading to widespread reliability and compatibility issues, which are difficult to analyse and debug in a real-world scenario due to the unnecessary layers of encryption etc in the underlying protocol layers.
 

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True but the socket and standard that gets out to market first and more adoption initially will be the winner.
VHS/Betamax anyone?

I see your point regarding the depot but not all depots have that kind of power, on route charging is good if done right. Look at manchester picadilly station as an example. I have once seen a bus charging at that point yet it must have cost at least £15k to install that 50kw unit. a bus doing a decent route will need at least 100kw of juice really when laden up, AC or Heat blasting as season needs it.
in a 15/30 min stop getting on for 10-20kwh of juice into a vehicle the size of a bus is useless.

for charge rate like that we are already seeing some rates of 1000miles/hour...
 

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Unfortunately it's now just too late for that, and more unfortunately, we're stuck with CCS, which, at least protocol-wise, is a truly terrible standard.
It's way, way too complex for the task, leading to widespread reliability and compatibility issues, which are difficult to analyse and debug in a real-world scenario due to the unnecessary layers of encryption etc in the underlying protocol layers.
You just have to look at the amount of people moaning about CCS connections on DBT chargers to see how shocking it is compared to chademo.
 

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You just have to look at the amount of people moaning about CCS connections on DBT chargers to see how shocking it is compared to chademo.
...or how shockingly badly the protocol was implemented on those chargers...

Not an apologist for CCS in particular, but there are plenty of reliable car / charger combos out there. It does seem to be harder to get right!
 

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...or how shockingly badly the protocol was implemented on those chargers...

Not an apologist for CCS in particular, but there are plenty of reliable car / charger combos out there. It does seem to be harder to get right!
You say that, but I've not heard of the same issues on the Chademo side occurring, and its not just DBT units that are affected so cant just be blamed on poor implementation, if the standard was more locked down the issue wouldn't arise.. And strange that some cars are fine with it and others aren't as well ;)
 

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Mine is bigger!

@donald is right about charging; the entire process of charging should not exceed 1C, but it may reach 3C for short periods of time.

The transport sector might better be worth to look into supercapacitors and not batteries, since they're looking for high charging and discharging rates. I believe the Tesla Semi will not really be sold with the same technology it has today.

The Semi uses 1.5kWh/km (although unclear to me if when loaded or empty), so to travel 100km it needs 150kWh, which is impressive and I'm not sure how many battery packs can sustain this type of stress for very long; mind you, it doesn't take into account going uphill demand (peak), nor constant acceleration and deceleration (in towns). We drive our EVs a couple of hours per day at most, a truck is driven about 7 hours per day and that's a lot of stress on the batteries. It means that, if we agree with Musks predicaments of going 650km on a charge, it would have to pretty much be fully charged and discharged every single day of operation. Considering that the Tesla chemistry can hold about 3000 cycles, that pretty much limits the battery to 10 years of operation, maybe 3 at max capacity and the rest at lower and lower capacity.

A supercapacitor would be able to charge and discharge 1+ million times; they are cheaper to make than batteries, but take up a crap load of space (low energy density). So a combination of the two may be more intelligent, in which the semi uses supercapacitors for acceleration and going uphill.

To charge a supercapacitor though... I'm not sure ChaDeMo is the solution. 500kW charge rate is both immense (regular EVs) and puny (ships, planes, trucks); it may work though for the small Japanese delivery trucks!
 

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The only way for a faster charge rate is what they use for the Electric ferry and thats some thick cabling, not really for manual handling...
I agree Super Caps are probably good for a decent amount of heavy vehicle energy storage and they are light as well so dont impact weight too much but are so so bulky.

they could be a good way to even out the charge curve though and help regen on the long downhills that can occur often.
 

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You say that, but I've not heard of the same issues on the Chademo side occurring, and its not just DBT units that are affected so cant just be blamed on poor implementation, if the standard was more locked down the issue wouldn't arise.. And strange that some cars are fine with it and others aren't as well ;)
Think we're agreeing here...the Chademo side is fine, but the CCS side generally isn't. Worse on some cars than others too - appears to be down to subtleties in timing / handshaking etc - the protocol is really complicated as already noted. I follow a number of forums (fora?) for CCS cars, as an example the iPace is far worse than the eTron at failing on CCS chargers in general, and that has certainly been my experience.

One thing that is common experience is that the DBT chargers are very unlikely to work reliably for anyone on CCS.
 

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Think we're agreeing here...the Chademo side is fine, but the CCS side generally isn't. Worse on some cars than others too - appears to be down to subtleties in timing / handshaking etc - the protocol is really complicated as already noted. I follow a number of forums (fora?) for CCS cars, as an example the iPace is far worse than the eTron at failing on CCS chargers in general, and that has certainly been my experience.

One thing that is common experience is that the DBT chargers are very unlikely to work reliably for anyone on CCS.
Designed by the Germans for German BEVs
 

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Discussion Starter #16
The CCS issue appears to relate to the handshake required before electrons flow. And also doesn't seem to be just the chargers alone but also in part appears to be caused by the cars' own systems. I have had some DBT's fail with my Ioniq and some work fine. Also, some Engenie units work and others fail. We also see many reports about different cars at the same charger meeting with different experiences. As in all intermittent faults, this is proving to be difficult to isolate and rectify.

I was hopeful that I might discover what was causing my own mixed results when I persuaded Engenie to arrange a coordinated visit with their tech dept on line to log all of the data being produced as I attempted a charge at a specific unit that always fails for me. That visit took place just as the lockdown came on and the subsequent forensic enquiry never took place. Eventually, they may be able to retrieve that data and discover why my car, at that particular unit, always fails to charge but a few miles away at another of their sites it works flawlessly.

Whatever happens in the overall battle for supremacy between Chad and CCS they must solve this inconsistency if they don't want to grasp defeat from the jaws of victory.
 

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Designed by the Germans for German BEVs
Type-2 was designed by Germans as well (Mennekes). With exceptions, CCS charging units are becoming pretty much standardized and Bosch (German), Continental (German) and Magna (Canadian) are currently manufacturing the entire assembly for most of their customers. There are so few manufacturers that really manufacture such components by themselves.

The market though is more fragmented on the DCFC unit side; ABB, Efacec, Tritium and a few other large-scale manufacturers have gotten things right, but other smaller manufacturers, maybe in the quest of shaving some costs, have not been as careful.
 

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The big initial charging issue with CCS appears to be that instead of ramping up, the cars demand what they want, not what the charger can provide and the charger then knocks it on the head to safe guard itself.

This will only get worse as bigger batteries come to the fore wanting MAX Volts & MAX Amps at the start and the charger going, urm nah mate i can only do 402v's @115amp's here so bye bye
 

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Type-2 was designed by Germans as well (Mennekes). With exceptions, CCS charging units are becoming pretty much standardized and Bosch (German), Continental (German) and Magna (Canadian) are currently manufacturing the entire assembly for most of their customers. There are so few manufacturers that really manufacture such components by themselves.

The market though is more fragmented on the DCFC unit side; ABB, Efacec, Tritium and a few other large-scale manufacturers have gotten things right, but other smaller manufacturers, maybe in the quest of shaving some costs, have not been as careful.
When the Germans introduced Mennekes type2 with it's three phase functionality, at least they had the sense to stick with analogue American J1779
 
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