Are car companies betting on 800V high-voltage supercharging?
According to industry insiders, 2022 is the "first year of high pressure" for new energy vehicles. In 2019, after Porsche released the Taycan, the first model equipped with an 800V high-voltage platform, high-voltage fast charging has always been regarded as an exclusive configuration for electric sports cars. However, more and more new car-making forces and independent traditional car companies have begun to bet on the 800V high-voltage platform as a big move to solve charging anxiety.
A simple search can find that the current models equipped with 800V high-voltage platforms include Avita 11, Extreme Fox Alpha S HI version, GAC AION V Plus, Xiaopeng G9, etc.; there are even individual models equipped with 800V high-voltage platforms during publicity. , and slogans such as "5 minutes of charging, 200 kilometers of battery life" and "elimination of hybrids".
At present, mainstream pure electric vehicles use a 400V platform, and the DC fast charging voltage is also around 400V. From the physical formula P=UI (power = voltage * current), it can be known that if the voltage of DC fast charging is increased to around 800V, the charging current Under the same condition, larger charging power can be obtained.
In short, that is, in the same period of time, a model equipped with an 800V high-voltage platform can charge more power than a model equipped with a 400V platform, thereby achieving the purpose of shortening the charging time. Therefore, the 800V high-voltage platform is also regarded by independent new energy vehicle companies as a good way to "change a different way of thinking to ease the charging anxiety of car owners". So, in actual experience, are pure electric models equipped with 800V high-voltage platforms as good as the car companies describe?
High pressure "overcharge", harsh conditions?
For models equipped with an 800V high-voltage platform, terminal sales staff will surely boast their ultimate selling point of "5 minutes of charging and 200 kilometers of battery life", but what the sales staff will not say is that in order to achieve the ultimate high-voltage fast charging, there are certain requirements. prerequisite.
"Actually, if you want to achieve the high-voltage fast charging efficiency officially promoted, you usually need to use the official supercharger." Zhang Yu (pseudonym) is an electrical engineer at a new energy OEM. He said that the supercharger released by the car, It is often developed for 800V high-voltage platforms, and has the characteristics of high adaptability and high power.
As for the fast charging effect of "5 minutes of charging, 200 kilometers of battery life" advertised by some 800V models, it is naturally the result measured on the official supercharging pile. And this also explains why when new forces and traditional car companies release 800V high-voltage models, they almost always release super-charging piles supporting high-voltage platforms.
If it is replaced with an ordinary third-party public charging pile, the 800V high-voltage model needs to achieve the official fast charging effect, and the conditions are much harsher. After all, most of the mainstream DC fast charging piles in China are developed for 400V platform models.
"It's not that it can't be charged, the 800V high-voltage platform is also compatible with 400V DC fast charging piles, but the charging voltage cannot reach the 800V or even higher than the platform requires, and the charging efficiency is almost the same as that of ordinary 400V models." Zhang Yu said frankly before the DC fast charging piles built in one or two years can support a charging voltage of 200~750V.
As for the DC fast charging piles laid out earlier, the charging voltage is only 200~550V, which is far from meeting the overcharging voltage required by 800V high-voltage platform models. The only 200~1000V DC charging pile that can meet the 800V high-voltage charging needs is only the 200~1000V DC charging pile that has been launched in the last year, and there are currently few applications in the industry.
So, as long as you find a DC charging pile that supports 800V high voltage, high-voltage models can achieve the official fast charging effect? No, Zhang Yu pointed out that only talking about the charging voltage without talking about the charging current is a hooligan.
"Even if it is the latest 200~1000V DC charging pile, it depends on the maximum charging power." For example, a single-gun DC charging pile that can support a maximum voltage of 1000V and a maximum charging power of 160kW can be charged at a demand voltage of 400V When, roughly calculated, the maximum theoretical current is not more than 400A.
However, when the demand voltage is 800V, the theoretical maximum current output by the charging pile is not more than 200A. In other words, no matter how much voltage is required when the vehicle is charging, the output charging power of the DC charging pile will not be greater than the maximum power. "If you want to achieve DC charging for 5 minutes and a range of 200 kilometers, the charging power must be at least 300kW."
As for some car companies, the charging efficiency of 800V high-voltage platform models on third-party DC fast piles is still higher than that of 400V models through car media evaluations. Zhang Yu emphasized that similar evaluations do not talk about demand voltage, When we talk about current, we only talk about the "obfuscation" of charging power.
It can be seen that if consumers listen to the selling point of the 800V high-voltage platform model of "charging for 5 minutes and have a battery life of 200 kilometers", buy a high-voltage platform model, and after leaving the 4S store, if they want to achieve the fast charging effect of the promotion, or find the official layout. Supercharging piles, or wait for the market to force the charging industry to change.
Another "autonomous driving" behind the gimmick
So, if you want to experience the "supercharging" pleasure of an 800V high-voltage platform, is it simple to wait for car companies to deploy supporting super-charging piles, or wait for the market to force the charging pile industry to change and charging stations to replace high-voltage and high-power DC fast-charging piles Simple? It's not easy, to tell the truth.
The first is the construction of piles by car companies. It is not easy to popularize high-voltage supercharged piles in major cities in China based on the strength of OEMs alone. However, the bluffing stunt had to be done. In April of this year, a new car-making force announced that it would take 3 years to lay 10,000 supercharging piles in China.
At first glance, 10,000 supercharging piles seem to be a huge number, but compared with the current domestic public charging piles, 10,000 supercharging piles seem to be a little insignificant. According to the charging alliance data, as of July this year, the total number of public charging piles in the alliance reached 1.575 million, of which 684,000 were DC.
Guolian Securities estimates that by 2025, the number of domestic charging piles is expected to reach 9.3 million. Obviously, it is difficult for pure electric vehicles to “eat enough” if they only rely on thousands and tens of thousands of super-full stations of car companies to deploy in a few years.
Therefore, the way to experience the pleasure of "supercharging" in the short term can only be achieved with the help of private capital and the power of charging enterprises to realize the iteration of charging piles from the 400V platform to the 800V high-voltage, high-power charging platform. Difficult to understand? It's ok. In other words, let the charging station operator replace the high-voltage DC fast charging pile.
"The charging station is not a charity organization. Who would be okay to replace the latest technology because of a new technology iteration?" Talking about the topic of DC charging pile iteration, the staff of several charging station operators in South China said that in the short term Inside, the company will not replace new piles because of the launch of 800V high-voltage models.
Among them, Ajie, the operation director of a charging company in Shenzhen, revealed that unless a new charging site is opened, it will consider "buying a new one instead of an old one" and adopting the latest high-voltage DC charging piles. It will take a few more years of service to be replaced.
"Now the company still has more than half of the DC charging piles, and the highest voltage is only 550V, which was launched the year before." Recover the cost, and then consider the return on profitability.
Even if only the charging module inside the charging pile is upgraded to have a wider output voltage and greater charging power, the cost is not cheap. According to industry insiders, at present, the price of mainstream wide-voltage 30kW charging modules is often more than 2,500 yuan.
Therefore, Ajie said frankly that it is impossible for the operator of the charging station to rashly update the equipment regardless of the hardware cost and profit target because of a new technology in the industry. What's more, whether the charging station can be equipped with high-voltage, high-power supercharging piles depends on the limit of its grid load.
"What's more, electric vehicles have been selling well in the past year, and the current situation of charging piles is "less than demand", and the problem of "difficulty charging" is common in some first-tier cities. Now, who would be picky about the old and new technologies used by charging piles?"
Because of this, Ajie said that the charging station naturally does not have the power and pressure of hardware and technology iteration, and the industry change is of course slow. Considering that the normal use of DC fast charging piles has a lifespan of more than three years, it may take three or five years for most of the DC charging piles in the industry to iterate from 400V to 800V high-voltage platforms.
In other words, the 800V high-voltage platform models purchased by consumers for the "overcharge" function are tantamount to the same models that are equipped with a large number of sensing elements and cameras, but can only achieve L2-level assisted driving. The so-called selling points are pure "futures".
"Getting on the train" requires "system engineering" for high voltage
Just like whether the mainstream technical route of new energy vehicles in the future is pure electric or hybrid, in the field of pure electric vehicle energy supplementation, there has always been a debate over the technical route-whether it is an 800V high-voltage platform "overcharge" or a battery swap model.
Some consumers choose pure electric vehicles that can be replaced and recharged in order to "bet the future", so why can't someone buy a high-voltage platform model that can achieve 800V "charging for 5 minutes and a range of 200 kilometers" and is compatible with 400V platform charging Woolen cloth?
Once three or five years later, most charging piles support 800V high-voltage and high-power charging. The so-called "futures" products purchased at this time are tantamount to walking in the forefront of most users. I'm afraid, that in just three to five years, new technologies have been born in the new energy vehicle industry, making the "futures" purchased by users become outdated products.
"Before, the high-voltage systems of pure electric vehicles were almost all 400V. It was only because of the core components of electronic control that silicon-based IGBTs generally could not withstand too high voltages, and at the same time, it was determined by considering the tolerance of other components." Zhang Yu emphasized, the vehicle from 400V to 800V high-voltage platform is a "system engineering."
Although silicon-based IGBTs can already withstand high voltages of more than 1000V, considering the characteristics of low loss and high frequency, 800V high-voltage platform models generally use SiC (silicon carbide) MOS instead of silicon-based IGBTs. It is at least 3 times more expensive than ordinary silicon-based IGBTs.”
He joked that even if the 800V high-voltage platform can halve the working current of the whole vehicle, it is beneficial to save wires and copper materials. However, the price of wires and copper materials saved is not even enough to fill the price difference between SiC and IGBT. "The 800V high-voltage platform can make vehicles lightweight, but there is still a question mark for reducing costs and increasing efficiency."
In addition, when the high-voltage system of the vehicle battery pack is iterated to 800V, the motor, electronic control, air-conditioning system, etc. matched with the whole vehicle need to be matched to work at the 800V voltage correspondingly to obtain the highest working efficiency and energy conversion efficiency.
Therefore, it is a big challenge for the whole vehicle parts supply chain. A large number of new components and electrical equipment need to be run in with the new technology platform, and the stability needs to be verified. At the same time, the cost of the supply chain will rise in the short term, which will eventually be reflected in the selling price.
Zhang Yu even revealed that in order to blindly "get on" the 800V high-voltage platform, some OEMs will even adopt "partial high-voltage" means, that is, parallel 800V batteries and mix and match the motor, electronic control, and electrical methods of the 400V platform to achieve high-voltage gimmicks.
"Is it necessary to boost the 400V charging pile? The battery's 800V power is supplied to the motor, electronic control, and air conditioner. It has to be stepped down. I don't know where the conversion rate is low. Such a high-voltage platform is the most meaningless and deceiving. ” He also pointed out that similar means of high and low voltage mix and match, often make vehicles have safety risks.
It is not difficult to see that in the long run, the 800V high-voltage platform is true "another way of thinking" to solve the anxiety of battery life and charging of pure electric vehicles. In the "run-in period" stage, consumers should think twice before purchasing related models.