[RahulNagaraj]

According to a media report, Electrify America will soon test a system that will cut off charging when the electric vehicles hit 85% battery capacity. In addition to that, EV owners who stay on for longer could end up getting penalised.



The decision to penalise EV owners is part of Electrify America's solution to reduce "charge hogs" - drivers who keep their EV plugged in for longer than needed. As per Electrify America, their EV chargers will cut off once the vehicle reaches 85% capacity. Post which, there will be a 10-minute grace period. If the drivers don't remove their EVs by then, they will be levied with a 40 cents per minute fine. Initially, the company will implement this at their 10 busiest charging stations in California.

Tesla also has a similar feature on its supercharger network. Here, the superchargers cut off electricity once the EV reaches 80% charge, however, owners can continue charging if they want.

Source: CNN

Link to Team-BHP news

[SKC-auto]

It's just one operator right? The headline sounds like a new legislation in US.

[amit_purohit20]

If I understand correctly, this rule is being enforced to ensure other person gets to charge his car. Nothing related to consuming more electricity or causing reduction in battery life.

[DIY410]

Fortum had initially done the same in India. They would add per minute cost to those charging above 85% but later on withdrew it.

As more and more EVs hit the road this is bound to happen.
For example, a Tiago EV would consume around 7kW when it's SOC is about 90%, people charging to 100% SOC should shift to AC charging. But they won't because they are lazy.

Imagine a Tiago/Tigor EV owner deciding to charge in a 120kW charger, those doing highway runs not only charge these Tiago EVs more frequently because of the small size battery but Tata vehicles other then Curvv have a really slow charge speed.

If they design a charger with four CCS2 guns, but at any given time only two vehicles can be charged with DC current. Those EVs users who has a Tiago or a person who is not going to remove their charge gun until 100% SOC is achieved. The charger should disconnect the DC HV relay and give the signal to the car to start accepting AC current.

So for this to work, the CCS2 plug needs all of the Type 2 AC pins to be physically present and not just the signal pins. Some EV can charge at 11kW or 22kW because they have on board 3 phase AC charger.

This way they can make sure the person who has a EV with 1C or more charge speed doesn't get bogged down or the EV slot be wasted to a slow charging EV user who wants to charge to 100%. They will be automatically changed to AC charge at a lower price/kWh.

Those vehicles that can charge at a speed higher then 7kW even at 95% SOC should continue with DC charging but with a time based flexible penalty relative to chargers peak speed for those charging above 85% SOC. So this forces them to switch to a lower kW DC charger if its present in the same location or opt for a AC charging automatically by disconnecting the DC relay.

Now one might think why not share the DC charger power as per demand with all the cars connected with respect to their charging speed. This cannot happen unless the cars have a identical battery voltage, chemistry and are at the same SOC, especially if its a car with a NMC battery. This is also the reason why a 120kW or 60kW dual gun charger can operate at either 50% speed max when two cars are connected or at 100% speed when one car is connected.

Now in theory they can add another DC to DC in the charger to match the voltage of various cars but this increases the cost and makes the circuit complex like handling ripple voltage etc

[Pontiac]

Not bad considering $24 for 1hr of extra parking hour. Considering this is USA, I am sure people will keep their vehicle on the charging bay paying the $24 fine.

On a separate note, this fine system should be implemented in gas stations. I have seen weird behaviors of Americans parking their car on the gas station terminal while they go shop or have a bite at the gas station eatery. All this while people are waiting to get a spot to fill gas.

[oakpr]

We need this in India too, but we may not need any fancy technology solutions (yet). Benefit of cheap labour is that we can quickly migrate from "customer self charging" model to "attendant charging" model. It can address few problems at once:

1. Attendants can direct slower DC rate cars to appropriate 25kw or 30kw chargers, while keeping 60/120 kw chargers free for cars that can make use of it. This of course is traffic based discretion, and may not always work in peak holiday season.

2. Attendants can warn customers upfront and disconnect cars once they drop to 7kw charging speed. It's easy to estimate charging time and customers can adjust their stop accordingly. In my experience, most customers do not argue.

3. Attendants also have ability to stop charging and disconnect charging gun. I don't know how, but I have seen Belgavi Gogte Plaza attendant doing this meticulously. While the car is still parked in place, it at least frees up the gun and shows up on app as vacant.

I'm not a fan of charging the customers extra. It leaves bad taste with those who genuinely overran their time, while also competing with parking fees as mentioned by @Pontiac.

[wocanak]

Originally Posted by DIY410

Now one might think why not share the DC charger power as per demand with all the cars connected with respect to their charging speed. This cannot happen unless the cars have a identical battery voltage, chemistry and are at the same SOC, especially if its a car with a NMC battery. This is also the reason why a 120kW or 60kW dual gun charger can operate at either 50% speed max when two cars are connected or at 100% speed when one car is connected.

Can you elaborate on this point? I was thinking it is just some limitation/shortcut in the current chargers and future equipment should be able to divide the power arbitrarily between cars, at least for the most common ~400V cars. You seem to be saying its some fundamental limitation.

[DIY410]

Originally Posted by wocanak

Can you elaborate on this point? I was thinking it is just some limitation/shortcut in the current chargers and future equipment should be able to divide the power arbitrarily between cars, at least for the most common ~400V cars. You seem to be saying its some fundamental limitation.

It is a limitation of the current chargers or probably more to do with the cost. In the present chargers they just combine two identical DC power sections in parallel to get full power or split them into two at half power. This saves them a lot of cost during manufacturing, BOM etc. Its also easier to replace, shutdown or disconnect the faulty section without effecting the working charger section other than operating at 50% capacity.

If they want to split the power proportionally as per each individual cars requirement, then there are lot of technical challenges which require lot of complex DC-DC, DC droop controller, filtering circuits etc.

Its not that it cannot be done but it will cost a lot more. One has to also factor in the effect of a internal section of charging unit going offline due to malfunction. How the controller algorithms compensate. So there are a lot of safety challenges. It may be the case that it's cheaper to just have more indvidual chargers than having a complex charger with proportional shared power output.

[nettooran]

Originally Posted by oakpr

We need this in India too, but we may not need any fancy technology solutions (yet). Benefit of cheap labour is that we can quickly migrate from "customer self charging" model to "attendant charging" model. It can address few problems at once:

1. Attendants can direct slower DC rate cars to appropriate 25kw or 30kw chargers, while keeping 60/120 kw chargers free for cars that can make use of it. This of course is traffic based discretion, and may not always work in peak holiday season.

2. Attendants can warn customers upfront and disconnect cars once they drop to 7kw charging speed. It's easy to estimate charging time and customers can adjust their stop accordingly. In my experience, most customers do not argue.

3. Attendants also have ability to stop charging and disconnect charging gun. I don't know how, but I have seen Belgavi Gogte Plaza attendant doing this meticulously. While the car is still parked in place, it at least frees up the gun and shows up on app as vacant.

I'm not a fan of charging the customers extra. It leaves bad taste with those who genuinely overran their time, while also competing with parking fees as mentioned by @Pontiac.

I dont think that will work in India. There are lot of " Janta hei mere baap kaun hei" types still roaming aroung. The poor Security stands no chance.

The best option is to change premium for the final slow charge. People who are in dire need can still continue if there is a need. Most of them will surely drop off.

[anandhsub]

Originally Posted by oakpr

3. While the car is still parked in place, it at least frees up the gun and shows up on app as vacant.

Isn't this worse? The gun shows as vacant and a car arrives to charge but is unable to because a car is parked.