China State Grid Electric Vehicle Expo
On October 22, I participated in the 2021 China State Grid Electric Mobility Expo in Hangzhou. The expo brought together mainstream domestic EV chargers and related support companies. Different from previous exhibitions of this kind,
many companies have displayed low-power DC EV chargers this time, ranging from 3.5kW to 30kW, mainly focusing on 20kW.
Note: Low-power DC EV charger displayed by various exhibitors during the exhibition
Simple popular science: In the past, our electric cars had two charging ports:
an AC charging port and a DC charging port, which is what car owners call a slow charging port and a fast-charging port.
The current slow-charging EV chargers on the market are mainly concentrated in the power of 7kW,
and fast EV chargers have increased from 60kW to 120kW, and there is an even higher trend.
The low-power DC EV charger can have a larger charging power than the slow-charging EV charger, generally below 20kW,
while the charging connector uses a DC charging port—generally a fast-charging port.
There has been a voice in the industry over the past few years that the onboard charger (ie OBC) is removed from the car so that the entire car only retains the fast charging port.
Note: The picture shows the schematic diagram of the on-board charger
1. Why do low-power DC EV chargers?
I communicated with various exhibitors at the exhibition site, and they gave different answers.
Some say that low-power DC EV chargers charge faster than slow EV chargers, and the cost is cheaper than fast EV chargers.
Some say it is suitable for shopping malls, scenic spots, and other places, users will stay for 1-3 hours. The normal AC EV charger is too slow, and the fast EV charger is wasteful. The low-power DC EV charger is just enough and can install a few more than the fast EV charger.
Some say that the low-power DC EV charger has communication, which can realize orderly charging, V2G, etc.
Are they right? It’s all right, but it’s not enough to support the trend of low-power DC EV chargers. It can only be a small subdivision scenario. But I vaguely feel that things are not that simple.
Take a look at the current installation situation of private EV chargers for electric vehicles.
In the early days, the number of electric cars was small, and users could basically install EV chargers after buying electric cars. The construction of such private EV chargers is random.
Since then, the purchase of electric vehicles has become an inevitable trend. The demand for installing EV chargers has skyrocketed, but the electricity load of the city or community is limited. After the disorderly installation of EV chargers in the past reaches a certain level, it will inevitably lead to the failure to install EV chargers for people who buy electric cars later.
There is randomness in the early stage and inevitability in the later stage. This contradiction is very common in many first- and second-tier cities. The property refuses to install EV chargers because of insufficient capacitance. As a result, many new electric vehicle owners cannot enjoy charging at home.
If electric cars cannot be charged at home, the so-called convenience and economy will be greatly reduced.
Imagine if you have an electric car, would you be willing to charge it with public EV chargers every time you go outside?
Without solving the ultimate community charging problem,
electric vehicles cannot be completely released into the huge market of millions of households.
When there is a problem in the market, it is necessary to find a solution in terms of policy, technology, and business model. Low-power DC EV chargers are one of the technical solutions.
The core contradiction of the problem is the increasingly tense electricity load and everyone wants to charge in their own parking spaces.
Ni Feng, deputy director of the Technology Strategy Center of NARI Group, believes that the best service objects for low-power DC EV chargers are non-operating vehicles,
such as private cars, official cars, and other vehicles parked for a long time. The power does not need to be too high, 3.5 -7kW is enough,
and the priority is to ensure that everyone can charge, and then solve the problem of charging speed.
In the past 2 years, the industry has been conducting an orderly charging trial of the AC EV charger. Trying to turn the EV chargers in the regional unit into an energy and data exchange intermediary. On the one hand,
it communicates with the vehicle terminal in real-time to get the charging data, and on the other hand,
it must respond to the electricity load in the regional unit in time to ensure the safety of electricity use. At the same time, the EV charger in the area can be connected to the Internet for unified management.
Because it is not supported in the current standard, AC EV chargers need to be modified and upgraded. Because of the DC properties of low-power DC EV chargers,
they can refer to existing standard protocols to a certain extent.
On the one hand, charging equipment and operators want to push low-power DC EV chargers, on the other hand, OEMs seem to have plans to remove OBC.
These two ideas collide together, will low-power DC EV chargers and the removal of OBC become a trend?
Note: China Wenzhou Bluesky EV chargers
An electric power expert from State Grid said that the State Grid is currently experimenting with low-power DC EV chargers,
not only for the current orderly charging but also for the future interaction between V2G and the grid.
Whether it will become a mainstream trend still depends on the market choice.
In a conversation with Zhu Yulong, a special author of the “Electric Vehicle Observer”,
he talked about the essence of solving the private charging problem as fairness and efficiency.
In the early days of the industry, in order to prioritize efficiency, we started from slow charging to fast charging. In terms of a private EV charger, whoever has an EV charger will install it. But when it comes to the growth period or the outbreak period,
it is necessary to gradually shift to fairness first. Not a small number of people can charge at home,
and most people can only charge outside, and we have to find a way to solve the charging problem of more people.
2. Will OEMs remove OBC?
Why do OEMs remove OBC? What are the benefits of removing OBC?
Zhu Yulong said: “For the car, the weight is reduced, the cost is reduced, and the failure points are also fewer. Remove the OBC and the corresponding wiring harness, and the slow charging socket can save about 1,500 yuan. For the whole vehicle, this piece still accounts for a large proportion. ”
The reason why there has been controversy in the industry has not been eliminated. In Zhu Yulong’s view, we can’t just look at the cost reduction on the vehicle side but may increase the cost on the marketing side. After all,
China already has a large stock of slow-charging EV chargers. The lack of a slow charging socket loses part of the convenience for users,
and the retention of competing models will increase marketing costs and ultimately may affect sales.
For this view, OBC company executives agreed, unless the user was given a low-power DC EV charger when buying an electric car,
but according to their calculations, the cost did not save much.
In addition, he said that the removal of OBC by OEMs depends on whether low-power DC EV chargers are popularized or become a trend.
At present, the OEMs they have contacted will not cancel OBC in the next 2-3 years.
It is worth noting that with the increasing number of electric vehicles, continuing to follow the existing method of buying electric vehicles and giving EV chargers will result in a lower and lower private installation rate. At this time, giving EV chargers becomes more and more meaningless.
When selling electric cars, the EV charger is an option, and users can install the EV charger before buying.
This will gradually become a trend in the future. After all, EV chargers entering the community cannot be led by the OEM, and they don’t want to be led.
However, it is always necessary to solve the charging problem for users. In the future, it is very likely that there will be community-based charging service providers to uniformly solve the community charging problem. At this time, it makes no sense to buy an electric car and give it an EV charger. Instead, it is provided by the charging service provider. Then it is possible to use a low-power DC EV charger here.
Therefore, whether EV charger manufacturers promote low-power DC EV chargers and whether OEMs remove OBC is still vague. No one can take the lead, but they will affect each other in the future development process.
As an OBC company executive stated above, it is necessary to solve problems and create value for users in the end. In this process, all technologies and models are worth exploring.