TU-TESL

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In recent years, with the advantage of high energy density, it has been widely used in passenger cars. However, the frequent fire accidents have caused consumers' concerns about the safety of new energy vehicles. The industry began to reexamine the differences between different materials of power batteries, and carried out a series of more rigorous experiments. The lithium iron phosphate battery, which was replaced by the ternary lithium battery, is now back in a safer and more reliable way. In the field of lithium iron phosphate technology, we have more than ten years of experience in technology development and application. On March 29, BYD's independent sub brand "Fudi series" released the first heavy-duty product - "blade battery" with lithium iron phosphate as anode material. Mr. chairman and President of BYD group revealed that "blade battery" is only used in BYD's pure tram type, which will be put into production in June. In the eyes of Mr. Wang Chuanfu, "blade battery" is a subversive product, and he even confidently said: "blade battery" embodies BYD's determination to completely end the safety pain point of new energy vehicles, and has the ability to lead the global power battery technology route back to the right way, and completely erase the word "spontaneous combustion" from the dictionary of new energy vehicles. " BYD "blade battery" is a kind of lithium iron phosphate battery. Compared with ternary lithium battery, lithium iron phosphate battery has better thermal stability. In theory, lithium iron phosphate battery can burn only when the temperature exceeds 500 ℃. Compared with the traditional lithium iron phosphate battery, the inner core of the "blade battery" adopts a special polar ear structure design, which makes the probability of short circuit extremely low; even in extreme cases, there will be no violent reaction inside the cell, further reducing the risk of spontaneous combustion. Compared with the traditional square shell cell with modular battery pack, the volume utilization rate of "blade battery" has been increased by more than 50%, and the volume energy density has reached the same level of the mainstream ternary lithium battery. "Blade battery" continues the long-life advantage of lithium iron phosphate technology, and can realize the life level of more than 3000 times of cyclic charge and discharge and more than 1.2 million kilometers of driving. The "blade battery" effectively controls the problem of iron dissolution of lithium iron phosphate battery, and slows down the capacity degradation of the battery. In addition, the thermal management system of "blade battery" has extremely high heat exchange efficiency, ensuring that the cell temperature is always kept in the optimal working range. "Needle penetration test" is recognized as the most rigorous test method for battery cell safety in the industry, and BYD "blade battery" has withstood this test. The principle of the experiment is: when the steel needle is punctured, the steel needle provides a short circuit path inside the battery. The electric energy of the battery is converted into heat energy and stored inside the battery. The short circuit causes the concentrated explosion and release of energy in a short time, which may cause smoke, night leakage or even fire explosion. Through a metal needle through the battery, simulate the battery performance when a short circuit occurs inside the battery. As the flagship car of BYD Dynasty series, BYD Han EV not only takes the lead in carrying the "blade battery", but also uses the brand-new interior design of BYD for the first time, which significantly enhances the sense of quality. It is learned by the city that BYD China EV will launch two versions of single motor and double motor, with NEDC driving range of up to 605km and 0-100km / h acceleration of only 3.9 seconds.