For models equipped with lithium iron phosphate batteries, you have one more guard with a "knife".
It has been almost four years since the appearance of the "blade battery", and I believe that in everyone's impression, the large blade about one meter long is the representative of this type of battery, and today there is a guard with a "knife" - Aegis short knife battery.
Aegis Short Knife battery
As Geely Automobile's official release of the latest generation of self-developed and self-produced "blade" lithium iron phosphate batteries, what is the difference between it and the previous "long knife battery" in terms of safety performance, cycle life, fast charging capacity and low-temperature discharge? Let's break it down.
It is designed to completely eliminate potential safety hazards
We know that the current blade batteries are all based on lithium iron phosphate cells, and CTP (cell-to-pack) technology is adopted, so as to reduce the structural parts at the module level, and simplify the assembly support structure on the battery pack, so that the entire battery pack structure is simplified as a whole, bringing an increase in battery energy density for "every inch of land and every inch of gold" electric vehicles.
At this point, the traditional long-knife battery has obviously taken the first step, but due to the long length, the transfer path of lithium-ion electrons from the positive and negative electrodes is also farther, and the internal resistance of the battery is higher, and the increase in internal resistance brings the direct problem of increased heat production of the cell, so there are higher safety hazards and performance attenuation. This is one of the basic logics for the birth of the Aegis Short Knife battery.
The comparison of the battery parameters of Aegis short knife and long knife is for reference only
It is reported that in terms of size, the Aegis short knife battery is about 40% shorter than the long knife battery, with a shorter length, smaller internal resistance, and less calorific power, which can effectively reduce the safety risks of itself. In addition, the internal wet-process double-coated diaphragm is used for better flexibility, which is not easy to break when puncture, and the damage aperture is small and the short-circuit area is small. The use of heat-resistant coatings such as alumina, similar to the addition of "isolation tape" between the positive and negative electrodes, can make the battery less prone to shrinkage during more stringent needling, avoid thermal runaway, and improve the thermal shrinkage performance of the separator.
Battery pack side pillar impact test
In addition to the optimization of battery cells and integration, the Aegis short knife battery pack is further upgraded and iterated on the basis of the original Aegis battery safety system, and adopts the CTB configuration that strengthens safety together with the body. It is reported that the battery pack adopts the patented design of the "Tianzi grid" frame; Three-layer composite material + DP980 steel "sandwich" structure bottom guard; The front part of the battery is designed with a special battery anti-collision beam; Two explosion-proof valves are used to quickly relieve pressure to ensure that the battery quickly balances the internal and external pressure, and the heat inside the battery can be quickly discharged, which greatly reduces the risk of battery explosion.
At the same time, there is also a Xingrui Intelligent Computing Center in the cloud as a guarantee, which can monitor the battery, electric drive, charging and distribution for 7×24 hours. It can realize cloud fault warning, online fault diagnosis, and online vehicle maintenance. By identifying potential safety risks of vehicles in advance and using intelligent after-sales service, the risk of user vehicle use is further reduced.
Aegis battery safety system test results
However, it is already 2024, and almost every manufacturer that makes batteries has a large number of safety designs, but whether it is good or not depends on whether it meets professional standards and whether it can undergo rigorous testing.
The Aegis short knife battery pack has passed the 6 "devil" serial tests carried out by the China Automotive Center, including 6 tests: seawater surfing, extreme cold on the plateau, high-frequency bottom scraping (3 times of bottom scraping), extreme rolling, side pillar collision of the battery pack, and blazing flame. Among them, a number of individual test requirements are higher than the national standard, and there are also a number of industry-first high-difficulty test conditions.
High-frequency scraping test
For example, the industry's first ultra-strict multi-frequency bottom-scraping test for single-battery packs, which passed the test ahead of schedule with a forward-looking ultra-national standard standard (the test standard is currently in the stage of publication and consultation), and the bottom-scraping frequency exceeds the current C-NCAP standard by 3 times; Among them, the 3° elevation angle is forward for 3 consecutive high-frequency scraping, simulating consumers being injured at the bottom of the battery in bad road conditions for many times, and verifying the protection ability of the bottom of the battery in an all-round way.
Eight-needle puncture test
In addition, the battery cell of the Aegis short knife battery is 8 times higher than the national standard, and 8 steel needles with a diameter of 5mm can be punctured and kept for 1h at the same time, and the battery cell does not smoke, fire or explode. At the same time, it is also the world's first battery cell that has passed the penetration test of 5.8mm real bullet shots, and it can still not catch fire or explode under extreme damage conditions.
Power battery quality challenge certificate
In fact, for the Aegis safety system supported by Volvo's security architecture, the 6 "devils" serial test may be just the beginning, Geely seems to have achieved "real gold is not afraid of fire" in terms of architecture safety and battery safety, but the Aegis short knife battery is not only safe, in fact, it is still a new generation of batteries that are very persuasive.
A new generation of batteries that listen to persuasion
For pure electric vehicles, the requirements for charging speed, battery life, and low temperature resistance are the real needs of consumers. Obviously, the Aegis Short Knife battery is here to meet these needs.
Aegis Short Knife battery
It is reported that the energy density of the Aegis short knife battery has reached 192Wh/kg, and the volume utilization rate has increased by more than 50%. After that, we should do a test of the endurance redemption rate on the first model Geely Galaxy E5, and I believe that the Geely Galaxy E5 will be very solid.
Charging speed has been greatly improved
In addition, the fast charging speed of the Aegis short knife battery is also very amazing, it is reported that the SOC can be charged from 10% to 80% in just 17 minutes. This is due to its short cell shape, which shortens the power transfer path of the cell; Carbon nanotubes with thinner diameter and longer length are used to make the negative electrodes more closely connected, creating a "highway" for ion transmission. More importantly, additives with lower film-forming impedance are added to the electrolyte to reduce the diffusion impedance of lithium ions, making it easier for lithium ions to enter the negative electrode.
Longer battery life
In terms of battery life, the official propaganda shows that the battery can still maintain a relatively healthy state after 3,500 cycles of charging and discharging cycles and a mileage of about 1 million kilometers. If we calculate that an ordinary family car has driven 20,000 kilometers in 1 year, wouldn't the Aegis short knife battery be able to "one generation of batteries and two generations of cars", and the battery can continue to be used when the age of the car has reached its age, which is really a bit incredible.
The lower the temperature, the greater the advantage
It is reported that the Aegis short knife battery has also been optimized for extreme cold, adding low-impedance film-forming additives to the electrolyte, which can reduce the internal resistance of the battery when discharging at low temperature, and significantly reduce the resistance of ion electrons when shuttling at low temperature. At the temperatures of 0°C, -10°C, -20°C and -30°C, the low-temperature discharge capacity retention rate of the Aegis short knife battery is higher than that of the long knife battery, with an average lead of 8.7%, and the lower the temperature, the greater the difference.
With a "knife" guard, escort
Obviously, the Aegis short knife battery, which has "military-grade" safety, has significant advantages in terms of safety performance, cycle life, fast charging capacity and low-temperature discharge compared with the "long knife battery" in the current industry. At the same time, the Aegis short knife battery has a shorter length, higher energy density, higher volume utilization, more flexible group arrangement, and wider adaptability, which can be compatible with different models such as cars, commercial vehicles, SUVs, and MPVs. This makes us even more excited about the Geely Galaxy E5, which will be equipped with this battery for the first time.
"History" is the least the most, I don't know, anyway, some people will panic
In my opinion, whether the knife is long or short, the knife is frightening to those companies that have not seriously devoted themselves to battery technology research. I think that behind the rise of China's electric vehicles, in fact, there are many Chinese car companies like Geely that focus on technology, through continuous innovation, continuous trial and error, and continuous exploration, and finally achieved results. And in this process, perhaps at the beginning there were doubts here and there, but gradually, slowly, those doubts became praise, and those ill-intentioned momentum builders became the dust of history.