“Almost everything you can think of car brands, and we explore in blade-based battery technology cooperation program.”
“carrying blade battery of new energy vehicles, will be ‘spontaneous combustion’ is a word dictionary from the new energy vehicles in completely erase”, BYD Group President Wang blade batteries conference of March 29 on said blade battery will change the industry relies ternary lithium battery, the power battery technology road leads back to the “right way” and redefine the safety standards for new energy vehicles, leading global battery safety to new heights.
Frequent exposure electric car spontaneous combustion accidents caused public concern about the safety of the battery
by a blade battery, refresh BYD energy density of lithium iron phosphate, lithium three yuan tied mainstream standards; experiments by needling, and insert the battery showed extraordinary “cool”, has become the only strict in this harsh battery test, to cross the border.
After years of competition and eliminated by a battery powered electric vehicles crowded the evolution of two-hegemony, ternary lithium batteries into the mainstream passenger cars, and lithium iron phosphate is firmly in control of the bus, bus market. Logical
behind: three yuan higher energy density lithium batteries, can support better battery life performance, but also to get a policy subsidies, which are to stimulate the enthusiasm of automobile manufacturers loading; and iron phosphate safety of lithium batteries better and live longer, for the number of occupants, the strength of large operators public transport, buses, this battery is the best choice. After
The “Blade battery,” the new generation of lithium iron phosphate product in the camp, three lithium batteries will be what kind of impact? It dominated the passenger car market, will be backward lithium iron phosphate camp do?
Why is the “Blade”?
Lithium iron phosphate BYD super cell (commonly known as batteries), due to the appearance of a flat elongated, is referred to as “blade batteries.”
by a blade cell conference documents and related patents, we can see the idea BYD enhance the energy density of lithium iron phosphate.
is actually insert the batteryCTP product, so-called CTP (Cell to Pack) refers to the unit cell (cell) is assembled directly into the battery pack, a battery pack and a conventional complex internal structure, first plurality of batteries to be assembled into modules, and then a plurality of modules assembled into a battery pack.
a brand of car battery pack structure schematically
Traditional internal battery pack needs to be arranged a plurality of longitudinal and transverse beams, to secure the battery modules, and to enhance the strength of the battery pack. Casing of the battery module and criss-cross beams to strengthen the battery pack, take up a lot of space, according to vice president of BYD Group, Verde battery Ho, chairman of Long said at a press conference blade battery, space utilization, conventional battery pack is only percentage of about 40, and the blade of the battery module and the reinforcing beam dispensed two links, improved space utilization percentage of 50, in other words, space for batteries in the battery pack 60 can reach percentages.
blade battery Why so long? The battery pack according to BYD patent application related documents show that the blade length of the cell may be between 600mm-2000mm, far more than ordinary lithium batteries. Cell length can be customized according to the size of the battery pack, since the length is sufficient, the core ends can be electrically “arrival” of the peripheral frame of the battery pack, it is fixed directly to the side beam.
The blade unit cell (cell) a flat elongated appearance (image information from related patents)
blade battery why so flat? Related patent document explains that batteries can be made into a flat shape to increase the effective heat dissipation area and improve heat dissipation efficiency.
Why can replace batteries longitudinal and transverse beams? Patent documents show that cell batteries monocoque shell of steel or aluminum material itself can play a supporting role. When the batteries are arranged in parallel within a battery pack, an alternative reinforcing structure to ensure the structural strength of the battery pack, so that not even less longitudinal and transverse beams.
According to what is described in the conference Long, insert the battery cell is a “energy body”, it is also a structural member, and further reference structure “honeycomb Aluminum”, the cell arrayHigh intensity upper and lower double-faced adhesive sheet structure, this allows the strength of the blade than the conventional battery pack, the battery pack “increased rather than decreased.”
a schematic internal configuration of the battery pack blade (image information from related patents)
this design will undoubtedly greatly improve the battery pack “volume energy density (Wh / l),” that is, the same size of the battery pack, it can put more batteries, which carry more power.
The electric vehicle battery pack is typically disposed between the front and rear axles on the chassis, the length, width and thickness are limited. With respect to the three yuan lithium battery, lithium iron phosphate bulk energy density of the battery is low, lithium iron phosphate block battery pack conventional structure, is difficult to support power carried by an electric vehicle over 400 km of endurance. According to information provided by BYD, a battery pack using the cell structure of the blade, the energy density of up to 50 volume percentage, the blade mounted battery BYD “Chinese” model expected to be available in June, the NEDC life reached 605 km, the basic ternary tied lithium advanced level.
electric vehicle battery pack is typically disposed on the chassis, limited volume (source schematic the network)
According to the relevant patent documents described, the volume efficiency of the battery pack insert can be further improved, about 40 percent “this can be designed from the original space utilization, increased to 60% or more or even higher.
in the ternary field of lithium batteries, the current cell is also advancing CTP technology directly into the package, but to enhance the rate of the blade significant cell gap. according Ningde times, three CTP element lithium battery pack volumetric efficiency can be increased by 15% -20%, to enhance the energy density of the battery pack 10% -15%.
“needle” represent?
In addition to energy density significantly addition to enhance the BYD battery blade also shows the amazing security.
reported that BYD blade battery recently completed a battery test the most difficult areas. “Prick tests “, which is the first battery by needling experiment.
prick tests of the cells, with a diameter of 5mm-8mm needle puncture, needle stays within the cell observed one hour after the conductive needle stuck into the battery, the battery may cause internal short circuit, may cause the heat released abruptly, out of control, and thus lead to ignition, deflagration and other consequences due to too difficult, there is no three yuan lithium battery through this a test, the new national standard “electric vehicles using lithium-ion battery safety requirements” (draft) even canceled prick tests.
on the blade batteries conference of March 29, BYD announced ternary comparative prick tests the full video lithium battery, lithium iron phosphate conventional blade and battery block battery video display, ternary lithium battery “a thorn i.e. burst” occurs within a couple of seconds intense burning, the surface temperature of more than 500 degrees, placed on the surface of the battery blown eggs; conventional lithium iron phosphate emitting smoke, but no fire occurs, a surface temperature of 200-400 degrees Celsius, the battery surface is baked egg ; Battery and the blade is no smoke and flame, the surface temperature of the battery is only 30-60 ° C, no change in the egg cell surface
.
the results of acupuncture three kinds of battery power
According to the Chinese Academy of Sciences, Tsinghua University Ouyang Ming Gao analysis, the reason why the battery can prick tests blade, partly because elongated battery cooling area is large, on the other hand, it is a circuit formed long battery short circuit, low heat production, these two factors determine the rate of temperature rise of the battery is small blade.
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a media exposure of the real capacity of the battery blade
Because repeatedly exposed fire incident, safety of electric vehicles raise questions, according to Chinese automobile Dealers Association released a report, due to the impact of the explosion of electric vehicles more than fire incident, nearly 30 percent of consumers worry about battery safety issues, and thus abandon the purchase of electric vehicles.
According to new energy vehicles national data research Alliance, the fire causes the electric vehicle has been identified, theBattery problems accounted for the highest percentage reached 58; and according to new energy vehicles Assessment Program (CEVE) data, the electric car caught fire accidents occurred in 2019, ternary lithium battery vehicles accounted for the highest, reaching 60 percentage, lithium iron phosphate battery vehicles accounting for only 5 percentage.
three yuan higher energy density lithium batteries, in nearly two years of passenger cars “endurance race”, the ternary lithium batteries automobile manufacturers to become the mainstream choice. Three yuan but poor thermal stability of lithium battery manufacturers to seek particular data look better, ternary lithium promote rapid “of high nickel” (Triad cathode material of lithium nickel cobalt manganese containing three elements, increase the proportion of nickel can improve the energy density, but the chemical stability of the battery decreases), a further increase in security risks.
by a battery BYD blades prick tests, by means of technological innovation, lithium iron phosphate product to achieve a higher stability and lower failure rate. “The new energy automobile spontaneous combustion dictionary erase” blade batteries, lithium batteries have three yuan dominated passenger EV market form the subversive impact it?
BYD blade battery mass production was in March, and for the first time mounted on Chinese models
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Wang at the press conference, the energy density of the battery unrealistic pursuit, completely “with biased” battery industry development path, and let the security reputation of new energy passenger cars paid a very heavy costs; and the blade release the battery is in the “correction”, not only to solve the new energy automotive industry security pain points, the entire industry will Forced to make a change.
about the prospects of the blade and battery impact on the industry, Verde battery Ho, chairman of Long revealed that “almost everything you can think of car brands, and we explore in blade-based battery technology cooperation program . ” Text / Great Wall of new media reporter Fu Xuefeng