electric car spontaneous combustion topic now more and more people’s attention, after all, who do not want their car suddenly burned up, do not want the next car spontaneous combustion . Recently, BYD released quot; insert batteries quot ;, at the press conference of BYD chairman Wang issued a rhetoric: To quot; spontaneous combustion quot; erased from the dictionary of electric vehicles in. BYD’s battery blade where exactly strong in? It allows Wang to issue such rhetoric.
battery why spontaneous combustion
before the blade, said BYD battery, or to talk about why the electric car battery will be spontaneous combustion. BYD blade shows cell conference site, ternary lithium battery, lithium iron phosphate and the conventional battery striker blade experimental video, can be found directly exploded three yuan lithium, lithium iron phosphate conventional surface also had a high temperature, insert batteries do not generate heat.
why this happens, but also from the characteristics of the respective lithium iron phosphate and the lithium three yuan both cells, ternary lithium battery energy storage density advantages of both the cold resistance and, on the energy density, ternary lithium battery because of the high voltage, energy density to achieve substantially 240WH / kg, almost 1.7 times the iron phosphate lithium battery 140WH / kg of. The second is that the low temperature resistance, ternary lithium low temperature lower limit value of minus 30 degrees Celsius, compared to the lithium iron phosphate at a low temperature limit of minus 20 degrees Celsius advantage.
and the advantages of lithium iron phosphate that is, the security will be higher, because the lithium iron phosphate in the thermal runaway temperature of generally 500 degrees, ternary lithium is less than 300 degrees, a number of high thermal nickel batteries runaway temperatures even lower than 200 degrees, compared to low risk of spontaneous combustion of lithium iron phosphate in the car at high speed and during fast charging, the second is followed by a longer cycle life, because the lithium iron phosphate of greater than 3500 charge-discharge cycles after the start of decay times before, that the useful life of up to ten years or so, but three yuan lithium battery charge and discharge cycles, compared with only 2,000 times, which means that the service life of only 6 years, more in life protrusion, and finally the manufacturing cost is lower, because the lithium iron phosphate batteriesNo precious metal, and therefore lower production costs.
on the blade or the battery essentially iron phosphate lithium battery, except that a new package structure, lithium iron phosphate itself all the advantages of safety is provided. And the new package can also bring the following benefits, energy density per unit space, structural strength, a larger surface area of the battery, and better heat dissipation. Wherein the thermal performance, resulting in lower blade surface temperature of the battery upon impact.
Characteristics
cells blade
in the conference, BYD claims blade battery has a high energy density, high security features . So how do these two points BYD is it?
When there is mention why spontaneous combustion, said battery, the battery is essentially a blade iron phosphate lithium battery, the characteristics of lithium iron phosphate on the blade of the battery is also present. Unlike traditional iron phosphate lithium battery, the battery through the blade structure innovation, a substantial increase in volumetric efficiency, and finally reach more charged batteries in the same space design goals. In this way the energy density of the battery on the blade has been effectively improved, a way to solve the low energy density of lithium iron phosphate problem. According compared to traditional BYD said mold has a battery pack, the weight ratio of the blade battery energy density can be achieved 180Wh / kg. Compared to the previous norm about 9 percentage improve battery, the battery in the same volume energy density of about 50 to enhance the percentage of iron than conventional batteries. The use of cell insert a new structure, a greater surface area, the heat dissipation will be faster, it is also possible overheating during rapid cooling, to ensure security.
uses a blade exactly what cell structure, to achieve the above advantages it? Now the mainstream is one cylindrical battery cell, connected in parallel in the battery pack, and then it is fixed by the structure of the battery pack. Blade structure of a cell is the use of a rectangular parallelepiped, each cell is a rectangular parallelepiped, and arranged side by side in the battery pack, just as a battery pack insertion blades, so is also the name of the blade to the battery. This cell cuboid housing itself has a very high strength, so that the battery can not erection bag structure to maintain the strength of the battery pack,And the use of a square cell, space utilization will be higher than the cylindrical batteries, thereby improving the energy density of the entire battery pack. A rectangular structure increases the cooling area thereof, but also rapid cooling to ensure their safety.
written in the last
BYD insert new batteries or lithium iron phosphate batteries nature, but by adjusting the structure, let With comparable energy density lithium three yuan, and the advantages of lithium iron phosphate to further deepen in the same volume, so again in the future using lithium iron phosphate battery models can and ternary lithium battery models have the same life the mileage. The new blade in BYD’s battery will Verde battery production, sale and open, so that in the future there will be a non-brand models BYD battery using a blade.
For these are theoretical analysis of the battery, the specific loading performance, but also the first use of BYD blade quot cell; Han quot; post-marketing specific performance.