I fail to understand the rationale behind that... I don't remember petrol pumps penalising me for fully filling up my car with petrol.
EV general discussion
- Thread starter Ricochet J
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I fail to understand the rationale behind that... I don't remember petrol pumps penalising me for fully filling up my car with petrol.
Caporegime
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Not saying I agree with it, but the rationale is that EV's charge extremely slowly past 90% capacity, even on a super fast charger.
It's quite frustrating to turn up to a busy charger and seeing people already at 90%+, slowly charging to 100 when they could more than likely get on with their journey.
It wouldn't be an issue if there was always a charger available.
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Because for most cars, the last 10% can takes as long as the first 0-70% on a rapid charger.
Generally speaking it’s much much faster to stop again, even for just a quick 10% zap than it is to sit there for 25 mins for the extra 20 miles of range.
…and before you say it, yes people absolutely do this despite it rarely making sense.
It’s about getting people to move on and not hogging expensive infrastructure that others could be using more effectively.
It’s no different to those that fill up their car and go and do their weekly shop in the filling station shop.
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I understand the rationale, it's the reasons behind it that I disagree.
To me ... a better solution would be to call 90% (or whatever that figure is for each battery type) as 100%.
Since the batteries are not designed to ever be "fully rapidly charged", why not intentionally cap their charge at 90%.
This is a case of the industry wanting to both have their cake and to eat it too.
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They already do. Many batteries have a gross size. Eg 82kWh and a net usable of 77kWh for example
An Ev6 on a fast charge (220kW peak) will hit 51C cell temp at about 91-92% and then it goes into limp mode and only charges at 5KW. So this is when you definitely want to leave a charger and continue with your trip
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and when you look at your car dash when it's hit that 91% - does it say "91%" or does it say "100%"?
Edit: let me give you an analogy...
Imagine you go to a restaurant, and order for 2 steaks.
They then give you 1 and bit steaks, and tell you that having that full 2nd steak would cost you more because their pan can only fit 1 and a bit steaks in it, so cooking 2 full steaks would take longer.
Does that make any sense?
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It'd be daft to have even more overhead battery capacity on most EVs just so the small handful of people who insist on using a rapid charger to 100% aren't there quite as long.
Far more sensible to just incentivise the few to move on a bit quicker wherever it potentially causes a small issue.
Far more sensible to just incentivise the few to move on a bit quicker wherever it potentially causes a small issue.
Nothing wrong with 100% and then driven. It’s 100% then the car is parked for weeks which is what batteries don’t like.
Why limit range (immediate comparison point for most) to save a battery life which isn’t that noticeable to most. It’s not difficult to keep it at 80% unless you are going on a long trip where you need all the range when charging at home or work. On longer trips charging to 100% on a fast will be slower anyway. Regardless of the increased charger congestion
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Why not just lebel that 91 as 100% then, and stop pretending like the car is designed to charge that last 9
That would impact the advertised range.
When there were fuel shortages 25 years ago, plenty of fuel stations had a maximum dispense value.
Last year people filled their vehicles to the brim when 1 diesel pump run out, then queues and no fuel ensued .
Forgive me but it is the sun.
https://www.thesun.co.uk/money/16239626/list-petrol-stations-30-pound-lomit-bp-shell-esso/
You can't fill your car up with petrol( not from a can) from home either.
Swings and roundabouts.
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Yes it would, which is my desired outcome - it would make the advertised range be the actual range the vehicle/battery technology is designed to get - not some "theoretical marketing number"
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Because it's only an isolated issue at congested rapid chargers, not a routine problem.
Cause it can? They absolutely smash fast charging but the battery cells got to hot on this particular day and so it throttled. An example of why charging to 100 as the operator of the car is a silly idea.
It would have been ok to charge the last 10% at a decent speed on a 100kW charger of course. But public chargers are expensive and I just only see them as a top up to get enough to get to your destination.
Obviously charging on a 7kW home charging this is not even a discussion so I’m not sure why you think 91% should become 100%. Don’t confuse the flow of the water hose with the size of the swimming pool
As said you seem confused with power kW and energy kWh.
Of course the range is related to the total energy. Go look at some charging curves to see how much power you can get in a battery at different SoC%
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The flow of water through the hose doesn't change depending on how full the pool is...
If the pool is empty it will be filling up the pool at exactly the same rate (volume per time period) as it would if the pool is empty.
And the cost of the water doesn't change based on how full my pool is.
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Yes that’s the point though it does change which is the topic here with fast chargers. Not the actual usable size of the battery. The pool is the same size. Just the hose slows down.
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The 20%-80% range is probably the most important figure IMHO
That's the number I go on...but then I bought my car. I'd imagine the vast majority of EVs are leased and people care less about the long term battery health. (More inclined to deep deplete or fully charge)
After 94k miles the OBD says it's 97%+ on the battery health.
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Are we currently living in an electricity shortage crisis?