800V high-voltage platform, a technology that improves the energy replenishment efficiency of pure electric vehicles N times, with the development of industry technology is gradually emerging, and looking at the players of this technology, we can see that a series of car companies such as Xiaopeng, Zhiji, Kia, Aion, and Ideal have launched their own 800V platform models, but I have not heard BYD's propaganda in this regard
It's all wrong, in fact, 800V for BYD has been realized as early as 2015.
Don't believe me?Take a look at this picture:
This is a nameplate of the vehicle, as can be seen from the picture, this is a BYD pure electric vehicle produced in 2016, and its battery operating voltage is 6336v。
That's right, this is a BYD Qin EV300.
It can be said that as early as 8 years ago, BYD had launched an 800V model, and the reason why it failed to promote it was actually quite embarrassing.
Because of the concept of being too advanced, BYD's electric models were incompatible with the charging environment at that time. You must know that in 2015, other brands of electric vehicles are generally still using 300-400V voltage, and 95% of public charging piles are below 500V. This means that BYD's high-voltage models cannot be charged on low-voltage charging piles.
Therefore, in order to solve this problem, BYD developed the first generation of boost technology at that time. This technology converts low voltage into high voltage, enabling 800V models to be DC charged at 60kW at a low voltage charging station.
After 8 years of continuous optimization and iteration, by 2020, BYD's boost technology has been applied to the Han EV, and its boost power can reach 100kW.
With the 2022 e-platform 3With the launch of the 0-architecture seal model, BYD's boost technology has been further upgraded to the third generation, increasing the boost power to 150kw.
However, looking at the domestic market, with the gradual iterative development of electric vehicle technology, its supporting charging facilities are also evolving.
For example, during 2015, China's new DC charging piles were mainly dominated by 500V, but by 2020, up to 85% of the new charging piles have been upgraded to 750V high-voltage piles. This means that the current BYD 800V models have excellent compatibility with mainstream 750V charging piles at home and abroad.
Speaking of which, does it mean that with the popularization of ultra-fast charging DC piles, the charging efficiency of our vehicles has been improved?
Nor is it true... If you haven't returned what you've learned to your secondary school physics teacher, you probably know that power = current x voltage.
That is to say, if you want to charge quickly, you must either increase the current or increase the voltage.
However, if you simply increase the current, it will increase a lot of heat, which will cause damage to the wire harness due to thermal ablation. Therefore, increasing the voltage became an inevitable option, which is what we call 800V today.
But the high-current solution is not impossible, after all, it is also a shortcut that can improve the charging speed, but there are relatively few companies doing this at present, such as Tesla and Zeekrypton and other car companies. Therefore, we have also seen that the existing public charging piles in the domestic market are designed in accordance with the 2015 version of the charging national standard, with a maximum charging current of 250A, and only 2% of public overcharging piles with a current of more than 300A.
In response to this problem, BYD proposed a solution that is more in line with the actual situation of charging in China, and the world's first dual-gun overcharging technology for passenger cars. Through this technology, public fast charging piles can be turned into supercharging piles in seconds, realizing multiple energy replenishment in a short period of time, so that supercharging sites can be spread all over the country.
Taking the DENZA N7 as an example, the maximum power of dual-gun overcharging can reach 230kW, and the public fast charging pile can be charged for 350km in 15 minutes.
In addition, the dual-gun supercharging technology has two charging circuits, which can operate independently or work together. Two fast-charging ports are arranged symmetrically on both sides of the rear of the body. In single-gun charging mode, vehicles with dual-gun overcharging technology are no different from single-gun vehiclesIn the dual-gun overcharging mode, the vehicle can intelligently call the output capacity of the second charging gun according to its own needs, doubling the charging current of the whole vehicle and reaching the maximum charging capacity.
When there is an idle pile at the fast charging station, the user can choose the dual-gun overcharging mode, and the vehicle will intelligently call the second charging gun according to the demand, doubling the charging current of the whole vehicle and giving full play to the maximum charging capacity of the whole vehicle. When the fast charging station is crowded, the user can switch to the single-gun charging mode, at this time, the vehicle is no different from the single-gun vehicle, and the normal charging will not occupy too much charging resources.
BYD has innovatively applied dual boost charging technology in dual-gun overcharging technology, which is not only fully compatible with the current wide range of 750V public fast charging piles, but also compatible with the 500V low-voltage fast charging piles built in the early stage of the market through the synchronous increase of the voltage of the two DC charging circuits, so as to achieve high and low voltage compatibility, and can be charged if there is a pile. It is worth mentioning that whether it is a double gun or a single ** type, it has 100% charging adaptability of the vehicle pile, and there is no need to distinguish between single and double guns, and it can be adapted by inserting a gun.
Not only that, in order to meet the demand for dual-gun supercharging, BYD has developed a unique "battery composite direct cooling technology". This technology gives full play to the potential of battery thermal management by laying direct cooling plates on both sides of the battery, increasing the cooling area of the battery by 100%. Combined with the vehicle cooling system, the heat exchange capacity has been increased by 85%. In addition, the zoned refrigerant adaptive control system adopts an independent control valve to intelligently adjust the heat exchange of the upper and lower cold plates in real time to minimize the temperature rise rate of the battery.
Under the charging condition, the zonal refrigerant adaptive control system can identify the charging power, automatically adjust and adapt to the high and low heat loads, and realize the reasonable distribution of cooling capacity. Under driving conditions, the system adaptively starts the upper cold plate by identifying the system pressure, which not only reduces the energy consumption of the thermal management system, but also ensures the cooling effect.
Not only that, for users in the north, whenever they enter the cold winter season, it is definitely a difficult challenge for electric vehicles, especially when charging and replenishing energy, because the power battery realizes charging and discharging through the transfer of lithium ions in the electrolyte and the embedding and de-embedding in the positive and negative electrodes. At low temperatures, the activity of the positive and negative electrode materials of the battery and the conductivity of the internal electrolyte decrease, the internal resistance increases, and the working current decreases, which is manifested as the attenuation of the usable capacity of the power battery, resulting in a "discount" in the mileage.
So how does BYD face this kind of problem?
In response to this problem, BYD has innovatively developed a full-scene intelligent pulse self-heating technology, becoming the first company in the industry to realize fast charging of cold cars at extremely low temperatures. Taking the DENZA N7 as an example, in the extremely cold environment of -30, this technology increases the battery heating rate by 230% compared with the traditional solution, and shortens the battery full charging time by 30%, so that users in northern China can enjoy a convenient fast charging experience in winter. It is worth mentioning that this technology can not only achieve self-heating during charging, but also intelligently start the self-heating function in the parking and driving states to ensure the stability of the vehicle performance in extremely low temperature environments.
It is worth mentioning that this technology can not only achieve self-heating during charging, but also intelligently start the self-heating function in the parking and driving states to ensure the stability of the vehicle performance in extremely low temperature environments.
So, how safe is it?
In fact, battery safety has always been one of the criteria for consumers to buy a car, and now BYD has a dual-gun technology, so can the safety be guaranteed?
After introduction, it is learned that the models using double-gun overcharging technology are equipped with DC charging positive and negative contactors in both charging circuits. When charging a single gun, the DC charging contactor of the other circuit will be disconnected, so that the interface is isolated from the high-voltage circuit, so as to ensure the electrical safety of the charging port without the gun.
In addition, both DC charging circuits are equipped with insulation detection. When the insulation resistance value of a certain circuit is abnormal, the vehicle can detect and implement corresponding protective measures in time, such as suspending charging, interrupting high-voltage output, etc.
The dual-gun overcharging technology also has an "intelligent dynamic diversion" mechanism. The control system will judge the risk of overcurrent in real time, and intelligently and dynamically distribute the current of the two guns according to the actual output capacity of the charging pile. Over-current protection is provided in the main battery circuit and two DC charging branches, providing double protection for the safety of dual-gun charging.
Finally, with regard to the existing charging piles, the dual-gun overcharging technology retains the advantages of high adaptability of single-gun charging piles, and is developed in accordance with the 2011 and 2015 versions of the national standard in terms of software protocols. When two charging cables are inserted into the vehicle, the pile automatically recognizes the version of the communication protocol, achieving perfect compatibility between the old and new standards.
In terms of high and low voltage, the dual-gun supercharging solution (high-energy version) has the ability to fully compatible with high and low voltage charging piles. The current of the main and auxiliary guns is collected in the power distribution module, and the motor boosts the module, so that the two guns can be charged at the same time in the low-voltage pile or the high-voltage pile. In addition, in the process of dual-gun overcharging, there is no need to use two additional mobile phones, and one mobile phone can realize the scanning code charging of two charging guns. The technical support includes the head charging operators with a large market share such as special calls and star charging.
Write at the end
Speaking of which, maybe you probably understand the advantages of BYD's dual-gun technology, but perhaps you will also have a question, why did BYD launch dual-gun technology?
In BYD's view, although the single-gun 800V high-voltage fast charging pursued by the new forces is fast, it cannot quickly achieve a wide range of ultra-fast charging piles, and it is not convenient for users to find supercharging piles. At the same time, due to range anxiety, users need charging piles closer to home or company, and the current layout and number of supercharging piles cannot meet user needs. In addition, the construction of charging piles requires a long construction period and huge funds, and it will take several years or even longer to achieve the geographical coverage of supercharging piles in the ideal state of users. Therefore, BYD pioneered the "passenger car double-gun supercharging" technology, making full use of the existing huge public fast charging pile ecology, and providing high-power fast charging efficiency of public piles with a "upstream" scheme