Recently, GAC Ion released a magazine battery plan and conducted live acupuncture testing on it. The biggest highlight should be that the power battery system with ternary lithium batteries as the module did not catch fire during the whole process of the acupuncture experiment. However, during the test, the steel needle pierced the vicinity of the battery case (or the battery cell involved in thermal runaway, or the case involving heat transfer) and the temperature rose to 686.7 degrees Celsius.
After GAC Aian launched the magazine battery solution, many media and netizens compared it with the blade battery system launched by BYD in 2020. The New Energy Information Analysis Network compares the battery solution of GAC E'an magazine with the BYD blade battery system based on the many information points currently available.
1. Analysis of GAC Ion magazine battery technical points:
GAC Ion magazine battery technology is mainly used in ternary lithium battery modules. I learned about the magazine battery assembly through some internal information. The height of the inner adapter cell is suspected to be nickel 55 type. Nickel 55 is a "high voltage single crystal" ternary material. The molar ratio of the cathode material of Ni55 is about Ni55%: Co13%: Mn27%.
During the acupuncture process of the magazine battery assembly, the process of suppressing the conversion of heat into energy through single crystal, special diaphragm and high temperature resistant electrolyte, the temperature increased to 686.7 degrees Celsius, the high temperature generated was converted into white smoke but no fire combustion. The magazine battery system detects the cell temperature through the 24-hour BMS electronic control system. Once thermal runaway occurs, the high-temperature heat dissipation function of the thermal management system starts to actively perform high-temperature heat dissipation; if the high-temperature heat dissipation capacity of the thermal management system is insufficient, reduce the temperature rise caused by thermal runaway , The heat-conducting groove of the battery case will release the energy converted from heat. At the same time, the 1400 degrees Celsius-resistant material at the top of the battery case will try to extend the time for heat to be introduced into the cockpit for occupants to escape.
2. BYD blade battery technical analysis:
blade battery is the most important technology that BYD put on the market last year.Starting from the relentless "prick oneself", it fully embodies the safety of blade batteries compared to traditional ternary lithium batteries and lithium iron phosphate batteries. This is a strategy to solve battery safety from the root (cell), so the blade battery no longer needs too much extra protection for the battery safety system.
During the whole process of the acupuncture test on the blade battery cell (about 28 minutes), an internal short circuit occurred and continued to release heat. But in the whole process, the outer shell of the large monomer lithium iron phosphate battery did not deform, which means that the heat released did not reach the level of conversion into pressure, the pressure relief valve did not open, and there was even no visible smoke and the battery shell. The deformation.
BYD chose the iron battery as the core of the blade battery, mainly because the lithium iron phosphate material itself has the four major advantages of high exothermic starting temperature, slow heat generation, less heat generation, and the material does not release oxygen during the decomposition process and is not easy to catch fire. However, because the energy density was lower than that of ternary lithium, many passenger car companies have fallen into the irrational pursuit of the energy density of power batteries in the past few years. defensive.
However, BYD has continuously improved the energy density of iron phosphate batteries through continuous technological innovation. At the same time, BYD integrates battery technology with large module CTP packaging technology and low-conductivity coolant. The length is 96 cm, width 9 cm, and height. The 1.35 cm single batteries are arranged in an array and inserted into the battery pack like a "blade" to form a blade battery system loading application. Taking into account the long battery life and high safety attributes of the power battery.
3. The fundamental technologies of the two batteries are different:
The technical solution of GAC Ion’s magazine battery is based on the characteristics of the ternary lithium battery, through cell improvement and packaging and control strategies to suppress thermal runaway. Therefore, the magazine battery technology pays more attention to the overall safety of the battery pack. The mesh nanoporous thermal insulation material, high temperature resistant shell, fully-fitted liquid cooling system and full-time control of the fifth-generation battery management The system is the key to the safety technology of the battery system of GAC E'an magazine.
BYD blade battery system is based on the safety of lithium iron phosphate battery.Through cell improvement and packaging technology and control strategies, the temperature rise will not be replaced by energy release when thermal runaway occurs. Therefore, BYD can focus its technological breakthroughs on the improvement of battery energy density and the reduction of battery pack costs.
In fact, GAC Aian’s magazine battery solution and BYD blade battery system are based on batteries, integrated battery assembly, heat insulation system, heat conduction technology, thermal management control strategy, and are adapted for the vehicle model. The combination of hardware and software appears.
GAC Aian has improved battery assembly and thermal management control strategies around safety because the battery cells are manufactured by a third party.
BYD has self-developed and mass-produced battery cells (electrodes, diaphragms and electrolyte), battery assemblies, and thermal management systems, and it has calmly improved safety in all directions.
The author has something to say:
Since China's new energy financial subsidy policy no longer uses mileage and energy density as standards in 2018, the industry has developed more rationally, and many models have begun to burst into flames due to safety defects , Combustion and even explosion accidents.
Jianghuai Weilai ES8, a new force in car-building, has been recalled from the "4-burning"; the traditional car factory SAIC New Energy’s Roewe ERX5 frequently bursts into fire and explosion accidents; therefore, regardless of the magazine battery solution of GAC Aeon and BYD’s The blade battery system must be integrated in the vehicle model and undergo a lot of market verification. It is pale to analyze and compare data based on data alone.
So far, several models equipped with BYD blade batteries have been listed, including the BYD D1 pure grid car-hailing currently operating in Changsha. These blade batteries have not spontaneously ignited during nearly a year of use. The accident, this is undoubtedly a positive publicity for the ternary lithium battery that has frequently spontaneously combusted a while ago. In terms of the technical features announced at the press conference, the GAC E'an magazine battery does have something.
The models equipped with GAC Ion magazine batteries will be launched later in 2021. At that time, the technical status of these two batteries and the vehicle will be studied and determined again.
New Energy Information Analysis Network Evaluation Group produced
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