Actually, Tesla model? The integrated large module based on 2 1700 adopted by 3 has shown the effect of this trend, compared with the previous model? 3 Only the battery cost is reduced by 35%, which is very helpful to Model? It is a blockbuster in the global market.
As exporters of new energy technologies in China, Contemporary Ampere Technology Co., Ltd. and BYD both released their own battery integration technologies according to this trend. Contemporary ampere technology co., ltd CTP(Cell? Where to? The technical route of Pack) is based on the high-nickel ternary lithium architecture, and its core is to reduce the number of modules, directly form a standardized battery pack by multiple large-capacity batteries, and then flexibly stack to form larger battery modules to meet the energy storage needs of different models. BYD's "Blade" battery is based on its expertise in lithium ferrous phosphate technology. The battery cell is also evolving to a large capacity, but the shape of the cell is flatter and narrower (the long side can be customized, and the maximum stable length of the cell can reach 2 100mm), so it is named "blade" figuratively. A plurality of "blades" are bundled together to form a battery module, and several large modules are combined together to form a battery module.
The two technologies can be said to achieve the same goal in reducing the module structure and improving the packaging efficiency, greatly reducing the cost of single-connection wiring harness and related processes and greatly improving the group efficiency (energy density), but from the application point of view, some differences can still be found.
As a single mass component arranged under the vehicle, the battery module must consider the adaptability of structural strength to the complex vehicle environment. The ability to resist lateral collision is the most obvious demand, and manufacturers often improve this ability through the structure and material application of battery pack shell. For long-term use of private cars, non-loaded bodies are generally used, and there are no girders. The battery structure also needs to be able to withstand long-term stress changes caused by repeated deformation of the body.
Through structural analysis, it can be seen that the contemporary Amperex Technology Co, Limited CTP technology is more susceptible to diagonal repeated shear stress because of the maximization of volume packaging efficiency, which is a great challenge for the connection between high-voltage wiring harness and cooling system, and the reliability of long-term use needs to be verified. However, BYD's "Blade" battery actually retains the overall configuration of module packaging and battery package packaging. At the same time, as can be seen from the patent drawing, it is possible to reserve deformation space for the battery pack packaging according to the needs of the vehicle model to avoid direct stress on the ultra-thin and large battery cells. From the perspective of structural durability, BYD blade battery packaging is easier to make reliable products.
However, such an insurance structure will also bring other problems. Judging from the published data, BYD uses the volume power density as a measurement index, but does not publish the commonly used weight power density data. It can be guessed that the specific energy of its structural weight superimposed on the iron battery itself is not high, which leads to no obvious breakthrough in its weight and power density on the standard metering platform of the Ministry of Industry and Information Technology. According to the previous data, the packaging weight power density of blade battery may reach about 180 Wh/kg, which is currently.
From the perspective of structural matching. As a single supplier of batteries and related technologies, Contemporary Ampere Technology Co., Ltd. needs to face more product matching considerations. However, from the current patent details, the height of CTP large module is unchanged (and not thin enough), and at the same time, it needs supporting shells to adapt to different models. Such a structure requires vehicle manufacturers to make corresponding adjustments in product planning, but the more difficult problem is that there is no large-scale sales as a support for development at present, and the risk of design adjustment is very great for a single battery supplier. This may also be because it is loud, but it is one of the reasons for the planned production (it is known that BAIC will definitely be put into production).
As BYD, which independently produces new energy vehicles, "Blade" battery may have considered the multi-specification adaptability requirements of its own products from the beginning. The smaller the narrow side of the "blade", the better, which means that the vertical height can be more easily adapted to the needs of high chassis and low chassis models. In the future, multifunctional vehicles with ultra-thin chassis can be developed on this basis, allowing users to use more space and tap the advantages of new energy vehicles. At the same time, we also see that the stacking application of this ultra-thin battery may be prepared for commercial and high-chassis large SUV products, which can store more energy.
Another feature of CTP battery in contemporary Ampere Technology Co., Ltd. is the large capacity of single battery. The capacity of single cell increased from the initial 50Ah to more than 200Ah now, which greatly reduced the proportion of cases. At the same time, under the condition of constant charge-discharge rate, more current can be output or received with a simple series structure (improving power and charging convenience). In addition, the information released by contemporary Amperex Technology Co., Ltd. shows that CTP battery will still be packaged in square shell, which should be a better choice considering the stability of high nickel battery at present.
The monomer design of BYD "Blade" battery surprised me at first. First of all, such a large single length is not a stable mechanical structure, and its deformation resistance is very weak when subjected to lateral force. Under normal circumstances, the battery will bring internal pressure when working, which will cause the shell to expand, thus generating pressure on the surrounding batteries. Therefore, we have to carefully consider the problem of drop when grouping, on the one hand, we must prevent earthquakes, on the other hand, we must eliminate lateral stress, and there is still no evidence in this regard.
Another technical challenge may come from the winding mode inside the battery. It is speculated that the battery core will take the form of multiple electrodes and multiple independent winding units. In fact, it can be regarded as a large battery composed of several small batteries, but these small batteries are encapsulated in a package. This is a great challenge to the uniformity of each battery cell, because the battery performance always follows Konigkin's law, and the worst one determines the overall performance!
Final summary. On the whole, contemporary Amperex Technology Co., Ltd., limited CTP battery and BYD Blade battery have their own advantages. Ningde CTP has higher power density and higher group efficiency, which is more friendly to the cost control of most automobile manufacturers, and it is easier to introduce products with longer battery life under the premise of a certain weight; BYD's "Blade" battery is more valuable and imaginative in terms of structural flexibility and durability, which greatly increases the performance of iron batteries and makes them return to the mainstream from commercial or low-end products, which has to be said to be a considerable progress.
From another point of view, the difference in technical architecture between the two companies also illustrates the fact that although both companies are technology exporters of new energy vehicles, BYD itself has advantages in technology accumulation as an automobile factory. This advantage may not depend on the improvement of a single index, but more on the understanding and rational solution of the user environment, which I think should also be the foothold of its long-term value.
This article comes from car home, the author of the car manufacturer, and does not represent car home's position.