Brief introduction of the difference between BYD and Tesla battery electronic control technology

Introduction: Tesla hundred kilometers acceleration and 17 inch by 3.9 seconds kill all physical buttons control screen to make silicon valley spirit into North America. BYD has closer to the character of the Chinese people, no adventure, not arrogant, starts from the desire of popularization of new energy cars, public transportation, and gradually develops a low-cost, popular hybrid and electric vehicles. In addition to BYD and Tesla, there will be more new energy in China meet in the future.

The future of electric vehicles represents the silence and patience. But on the Chinese and western representative: BYD and Tesla, but have something to say.

Bureau of cobalt and nickel aluminum lithium iron phosphate batteries

In the motor and control technology of documentaries, mature, electric car one of the most difficult dilemma of crack and the biggest competition comes from the battery technology.

The tesla Roadster electric sports cars in the early days, the volume is very small, 18650Cobalt acid lithium batteries, the batteries are usually used in mobile phones, notebook computers and other small appliances. Its biggest characteristic is to have a very high energy density, reached almost 170 watts/kg. But its thermal stability at the same time to ridicule, in 180 degrees will appear breakdown phenomenon and produce oxygen.

Tesla battery monomer

Later, tesla to compromise between the energy density, power density and safety, in the Model is using the modified model The ternary battery cobalt nickel aluminium cell, make the total number of cells, reached more than 8000 section, section Roadster over more than 1000 more, but the cost is decreased by thirty percent. However, limited cycles still become the shackles of the problem of batteries in electric vehicle applications, to once every two days of charging frequency calculation, about three to four years later, the battery will die.

Tesla this solution is to provide "without fault" battery warranty policy, namely the battery as long as it's not artificial damage, the collision accident damaged, can get eight years free warranty. And when the battery life expires, tesla will shoulder the battery recycling and renewed. Such policies as entry-level models to launch, the increase in sales for tesla brought very big pressure. This may also be its preparation is one of the reasons for the preparation of the world's largest battery factories.

BYD, by contrast, adopted by the lithium iron phosphate battery is the more widely used. It has the advantage of high thermal stability, when the structure is still stable in 600 degrees, because ferric iron ion is not active at the same time, it's hard to produce chemical change, this makes it relatively long service life, in theory, can be greater than the life of the vehicle, the long-term use of lower cost. At the same time, the lithium iron phosphate battery power density is better, can large discharge, good acceleration.

BYD battery pack

However, relative to the ternary lithium battery, lithium iron phosphate battery energy density is not advantage, about 100 ~ 110 w/kg, resulting in under the condition of the same weight, its shorter range and want to obtain a higher range, is hard to avoid the need to increase the battery weight, increase the cost.

Comprehensive performance, not all companies have tesla's software, battery management, so the lithium iron phosphate batteries or be valued by more and more practical types of batteries. This may also be common to adopt one of the reasons for the lithium iron phosphate batteries.

Because the battery has the characteristics of the tesla in its configuration, the thermal management system, the battery management system was carried out on a very in-depth design, to ensure that each battery unit under the regulation, the state data can be feedback, processing at any time. For a single volume very small cells, tesla compartment, should be independent closed to the steel surface system at the same time can be specific to each battery unit for cooling, reduce the temperature difference of each other, is also relatively reduces the risk of spontaneous combustion battery.

The tesla had an accident, the reason is generally comes from the battery pack after puncture local power lines caused by short circuit. Tesla currently doesn't solve the battery pack has been damaged by the impact of extreme explode combustion under the situation, only the protection of the high strength for the owner to more time to escape.

In fact, this is almost a common electric potential hidden trouble, for the function of battery management system put forward very high requirements. To in addition to routine monitoring of cell temperature, working condition, also need to quickly change in temperature, or extreme collision occurs immediately cut off the high voltage line. And thermal management system, battery management system upgrade will shorten the battery charging time, lead to higher charging efficiency.

In addition, how to ensure the battery and use efficiency under different temperature condition, and is engaged in the electric car research and development, production enterprises need to solve the problem.

Also need to mention is that tesla has been promoting is a pure electric vehicle products, and its high-end route, from high to low product ideas, also from the side reflects the market for electric vehicles inclusive not go far enough.

BYD future promotion of the "double with dual mode" car actually opens before the electric market, can promote plug-in hybrids as a transitional product. Compared with traditional gasoline vehicles, hybrid cars more fuel-efficient, and reduce the dosage of the battery, given the policy subsidy of new energy vehicles, car costs also got test, this is the product conforms to byd civilian route.

Synchronous and asynchronous motor

Current motor in the process of the leave the cell, arrived, need through the inverter, the dc "transform" into the ac motor drive, and then input motor, rotating by driving circuit to drive motor output torque. On the thinking of motor selection, tesla conservative estimates, using the current technology is more mature and wide application field of asynchronous motor, and locate common BYD is with a little difficult to understand the stubborn, chose a relatively "tough" permanent magnet synchronous motor.

On the working principle, there is no essential difference between both is depend on the electromagnetic induction between the stator and rotor and output torque. Through the establishment of rotor stator winding asynchronous motor magnetic field, and the permanent magnet synchronous motor as the name implies, the rotor part used permanent magnet materials. Choosing the right motor, will also produce certain remedy for battery, this will save a part of the battery cost.

The reserve of asynchronous motor technology is relatively mature, reliable, durable, high power motor factory or home refrigerators, washing machines, almost all can see the sight. This for costly electric vehicle, and is very rational, guileless. But at the same time, compared with other electrical appliances, electric vehicles for electric drive part of the pursuit of more detailed and highlight the deficiency of the asynchronous motor, in addition to the need to consume more power, the rotor also easy fever, speed performance is more common.

In order to improve the disadvantage of asynchronous motor, start out on the electrically controlled part tesla first articles, IGBT power to meet the high efficient substation control, and restructuring of electrical connection between the motor and the gearbox, improving the output torque of the motor at low speed.

Byd adopted by the permanent magnet synchronous motor, improved a lot in terms of efficiency and power density, speed is quicker than the asynchronous motor performance, and the structure is simple, it is relatively easy to maintain. But it is in the field of technical reserves, the application has not yet to mature, and contains rare earth permanent magnet material cost is higher has been the permanent magnet synchronous motor's ills. BYD to make this choice, on the one hand, save the drive for power demand to make the adjustment, on the one hand, also has brought the cost control is difficult. And how the magnet with lower levels of rare earth materials play to efficiency, may also need BYD to continue thinking.

Integration and reshaping, which is closer to the future

With the advent of ModelS ModelS, tesla to subvert their charging time, the number and area covered by aggressively expanding super charging pile, as well as the leading idea of making cars, the sales model, made the first time the "apple" company car. But it seems many traditional auto enterprise, tesla was born is not enough to have disruptive impact on the auto industry. And understanding of the mode of existence of new energy vehicles, also still have many differences.

In their own brands, "build tesla points minutes" became popular. As BYD new energy car companies first released grandiloquence, and more recently, Geely's eldest brother li also expressed a similar meaning. To return the original, perhaps because the tesla behind show advanced the concept of building cars, reflect its powerful technology integration, integration ability. From the point of the choice of the battery, motor, tesla, more interested in the existing mature technology motors, reduce the cost base product technological innovation, the integration between components to the biggest potential.

For at the same time, on the basis of technology research and development, the matching of automobile corporations, tesla is difficult to be regarded as a powerful car companies, from the perspective of the high-end models, a temporary lack of common models also makes the "revolution" in the field of new energy, a few minutes less but it and the development history of tesla supplement each other.

In fact, as the same building cars 10 years of BYD, there is no set up the absolute advantage in the field of new energy vehicles, and even often need to deal with questions from all directions and compared. But it is worth noting that BYD's ideas are not the same with tesla's products. Depends on vertical integration of industrial chain, BYD scored the most parts of independent production, in addition, the double with double mold core technology and the control unit is also from the independent research and development. Than tesla on the integration ability of innovation and perfection pursuing, BYD chose from the perspective of emerging technologies breach, it is more close to the innovation, the basis of but also to the enterprise technical strength reserve presents a big challenge.

Summary

Traditional car companies sedimentary experience building cars for many years, but are overwhelmed, can't spend too much energy on new energy vehicles, put the cart before the horse. Focus on new energy automobile enterprises in products more color of science and technology at the same time, owing to thin of the experience in building cars, also hard to avoid defects.

Ten years ago, the electric car market nearly flat, in a corner of the automobile products few takers. As the lithium battery technological breakthroughs, electric cars have the chance of a solid powder, gradually. This opportunity is also the pursuit of new energy automobile enterprise long-awaited moment.

Tesla hundred kilometers acceleration and 17 inch by 3.9 seconds kill all physical buttons control screen to silicon valley land of North America. BYD is closer to the character of the Chinese people, not adventure, not high, from the desire of popularization of new energy cars, public transportation, and gradually developed a low-cost, popular hybrid and electric vehicles. In addition to BYD and tesla, meet in the future will have more new energy in China.

Compete and competition market needs maturity and supply. Before that, the new energy automotive technology, policy, environment and product positioning, are facing similar problems. Like gold rush from the bottom of the river sediment, apart from the arm action, eyes focusing on the outside, it still needs time to push, make meaningless turbidity to sink into the river, and only stay clear.

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