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[YesAuto technology] BYD is a very representative Chinese brand, especially the launch of electric and hybrid models has given this company born in the battery industry a “technological innovation” halo. Another masterpiece in the field of new energy. As a plug-in hybrid SUV, while emphasizing energy saving, it also focused on promoting its strong acceleration performance. Presumably, BYD's positioning for Tang is not just about commuting and shopping. That being the case, we need to pay attention to Tang's chassis suspension structure to see if its chassis can hold such a fierce power.

Overview of BYD Tang's overall chassis layout:

Front suspension: the structure has not changed

Regardless of whether BYD’s fans can accept it or not, BYD’s engineers have obviously always “favored” Japanese brands, especially Toyota. Take BYD’s SUV models as an example, BYD S6 and S7 (hereinafter referred to as “S6” and “S7”) have obviously “borrowed” Lexus’s second-generation RX models in terms of appearance design and chassis structure. Will Tang, which is derived from the foundation, change this situation? Through our disassembly, Tang's front suspension is still loyal to Toyota's design.

In terms of some details of the front chassis, Tang and BYD’s previous works are also very similar. It should be said that this chassis structure is very mature. For BYD engineers, all that needs to be done is to optimize and adjust some characteristics of Tang. can.

In general, the front chassis of BYD Tang does not have much innovation. The overall structure basically follows the previous S6 and S7 models, which obviously has the shadow of Toyota. However, due to Tang’s particularity in powertrain and power output, BYD’s engineers have optimized some details for its characteristics. Although there is still a gap between this and the complete “autonomy” in many people's minds, the advantage is that it can effectively control the cost of development and production, thereby bringing affordable prices. At least at this stage, we do not agree, but we can approve of this approach.

Middle chassis: power battery pack

    As a plug-in hybrid vehicle with a cruising range of 85km, Tang's power battery pack is relatively large. BYD’s engineers arranged the battery pack in the middle of the chassis. Compared with arranging the battery pack in the trunk, this has two main advantages: 1. It does not occupy the trunk space, and the rear seats of the vehicle can be folded normally. Without sacrificing the practicability of SUV models, it can expand production capacity; 2. The height of SUV models is higher, and the center of gravity is also increased. Placing the battery pack under the vehicle can effectively reduce the center of gravity of the vehicle and improve driving stability. Of course, a huge battery pack is placed under the passenger compartment, which is believed to be helpful to the sound insulation of the chassis, but that is not the main effect.

Due to the addition of the battery pack, Tang's central chassis cannot be borrowed from previous SUV products. Instead, it should be inspired by some of its own pure electric vehicle e6 in terms of battery pack layout, control and safety protection. With regard to the low energy density of lithium iron phosphate batteries, BYD fans do not need to be concerned. BYD, which started as a battery, is obviously sober and forward-looking in this regard. At present, its existing lithium iron phosphate technology can no longer meet the requirements of the National 863 Plan for future electric vehicle power batteries in terms of energy density. Gradually shifted the focus of research to ternary lithium battery technology , I believe there will be breakthroughs in this area in the future.

Rear chassis and details: electric drive rear axle

I believe people who are familiar with BYD S6 and S7 models must know that these two cars use Toyota's two-link rear suspension that has been teased by many people. Two of the horizontally arranged links are slender, so many like to use the thickness The hero's friend is very disdainful of this. In this regard, BYD Tang finally made a change, and at the same time we can also see one of the “artifacts” that give it a leapfrog acceleration capability: the rear axle motor.

Although the shadow of the previous products can still be seen in the suspension structure, the feature that distinguishes Tang from BYD's previous SUV products is that it also has an electric motor on the rear axle, so it can achieve electric four-wheel drive conditions. In addition, in terms of rear axle power transmission, BYD’s engineers also installed an Eaton mechanical limited-slip differential for Tang, so Tang also performed well in our four-wheel drive test.

Demonstration of structure and principle of Eaton limited slip differential:

BYD Tang four-wheel drive test:

Due to the addition of the rear axle motor, the rear chassis of BYD Tang presents characteristics that are significantly different from other models. The self-designed suspension swing arm and integrated rear axle power system show that BYD has re-created on the basis of the original model platform. technical skills.

to sum up:

As a plug-in hybrid four-wheel drive SUV from a Chinese brand with 0-100km/h acceleration time of less than 5 seconds, BYD Tang itself has a lot of topics. After interpreting Tang’s chassis, it was found that its suspension structure is still derived from the previous Toyota/Lexus technology platform. However, due to Tang’s characteristics, BYD’s engineers have carried out some targeted transformations and optimizations. These transformations and The optimization is mainly concentrated on the rear axle part of the vehicle. From the final driving experience, the driving texture of the Tang chassis suspension is satisfactory, and the NVH level has also been improved to a certain extent compared with the previous products.

We often say that the development of new energy vehicles is a rare opportunity for Chinese auto brands that have a late start and a weak foundation, because everyone is basically on the same starting line in terms of battery, electric and hybrid power systems. The rise of Tesla is a good example, and BYD is not lagging behind; but as a car itself, it takes decades or even hundreds of years of experience in the development, design and tuning of the chassis suspension. Accumulation, in this regard, Chinese brands represented by BYD really need to continue to precipitate and explore, so as to develop truly completely independent high-level products.