When it comes to power batteries, the first thing that everyone thinks of should be CATL, which has the highest market share. Its ternary lithium batteries are widely used in new energy vehicles. However, according to August data released by the China Automotive Power Battery Industry Innovation Alliance, the monthly output of lithium iron phosphate batteries exceeded that of ternary batteries for the first time.
Of course, CATL has also launched lithium iron phosphate batteries, but the one that has been discussed the most is probably BYD’s “blade battery”. The blade battery has an energy density of 140-160Wh/kg. With its affordable price and safety performance of "no fire", it has won the recognition of a large number of consumers.
Seeing the great success of BYD's Blade Battery, other independent new energy and brands have also made efforts to produce their own "non-fire" batteries one after another, hoping to rely on the same outstanding safety to compete in the pure electric market. Get a piece of the pie. BYD Blade Battery has achieved so much success, do these later batteries really have a chance? Today, Brother Jiang will take a look at these batteries with everyone.
1. GAC magazine battery
Technical features: Add shell to protect the battery core
Battery energy density: 162.00-184.00Wh/kg
Among the many "non-fire" batteries, GAC's magazine battery should be the first to be released. On March 10, 2020, GAC Aion released a new generation of power battery safety technology, referred to as "magazine battery", and completed acupuncture experiments during the same period.
The experimental process showed that the stabbed battery core experienced thermal runaway, but only smoke emitted briefly, and there was no fire or explosion. After leaving it alone for 48 hours, the voltage dropped to 0V and the temperature returned to room temperature. During the process, only the stabbed cell module was affected, and it did not spread to other locations in the battery pack. Acupuncture does not cause fire, and what is more interesting is that GAC's magazine battery is still a ternary lithium battery that is easy to catch fire due to thermal runaway. GAC's move can be said to have rectified the name of ternary lithium.
Why did other ternary lithium batteries catch fire, but GAC’s magazine battery did not? In this regard, in addition to the key role of the "magazine" in the battery's name as isolation protection and limiting loss of control to a single compartment, the new ultra-high heat-resistant and stable battery core and the speed battery with good cooling function The fifth-generation battery management system is actually also very important for cold systems and being able to start the self-rescue program immediately.
It does not catch fire, the battery energy density is even higher, and the product has been mass-produced (it has been installed in new GAC cars such as AION Y). Under the synergy of these multiple beneficial effects, everyone feels that it can provide Ternary lithium battery has its name corrected. Can it compete with blade battery?
2. Extreme krypton core battery
Technical features: Improve the thermal stability of the battery core from the material level
Battery energy density: 176.6-250Wh/kg (The highest value is not in mass production)
Although the Ji Krypton 001 car has not yet been officially delivered, its battery has completed acupuncture experiments as early as July. According to the test results announced by Jikrypton, after the steel needle penetrated the battery pack and triggered thermal runaway, the "Jixin" battery pack BMS triggered a thermal event alarm signal in time.
At the same time, smoke appeared in the stabbed "pole core" battery pack, and the highest temperature of the stabbed battery core reached 801.4. Although the temperature was very high, the battery did not catch fire or explode.
After standing for 24 hours, the monomer voltage dropped to 0V and the temperature dropped to room temperature. The thermal barrier design and the entire package structure are intact. There is no obvious deformation, the battery shell is not charged, the internal fixed structure and high-voltage connections of the battery pack are intact, and there is no heat spread.
Although the experimental effect of Ji Krypton 001 is similar to that of the previous GAC magazine battery, its implementation method is completely different from that of shell protection. JiKrypton's "pole core" battery works directly from the source. It uses Ni55+ batteries to reduce the proportion of "nickel" content (the more nickel, the longer the battery life. In addition, the chance of causing internal instability in the battery is also larger).
The three elements of nickel, cobalt and manganese in the ordinary 811 ternary lithium battery are 8:1:1, but the ratio of these three elements in the NI55+ battery is 5:2:3. Such a ratio The nickel content is less than 811. Of course, lowering the nickel content is detrimental to the cruising range, but Jikrypton still optimizes the battery space by increasing the voltage (from 4.2V to 4.35V) and reducing parts, thus preserving the vehicle's cruising range. However, the fly in the ointment is that the cost of this kind of battery is relatively high. If the cost cannot be reduced, it will be difficult for it to defeat BYD.
3. Lantu amber and mica batteries
Technical features: Batteries are insulated by filling materials
Battery energy density: None -275 Wh/kg (max. Value is not yet in mass production)
Unlike the earlier batteries in the first two experiments, Lantu’s amber battery experiment has just been completed recently. However, what it does is not acupuncture thermal runaway experiment, but thermal diffusion thermal runaway experiment. It uses the internal heating method of the battery pack to heat the temperature of one battery cell and the surrounding battery cells to 300 C, artificially triggering thermal runaway, and then looking at the battery reaction.
The final experimental results showed that the Lantu amber battery passed the power battery safety inspection of the China Automotive Industry Center: after triggering thermal runaway, the battery pack did not smoke, fire, or explode. According to Lantu's battery engineer, the working conditions of this thermal diffusion experiment are more stringent than those of the acupuncture experiment.
How does Lantu’s battery do this without catching fire at temperatures as high as 300 degrees Celsius? The reason why it is called an amber battery is that each cell is wrapped in thermal insulation material, just like amber. This is similar to the Tesla Model 3 battery. The gaps between the battery cells are filled with insulating materials to isolate the battery cells one by one to prevent an individual soldier from losing control and burning the entire camp. However, due to the addition of insulating materials, the energy density of the battery will be relatively low.
Mica batteries are similar. Both use "three-dimensional insulation wall" technology. Only mica batteries add layered Al-Si mica and aerogel into the battery pack, and the battery core and Mica and aerogel will be stacked in layers like mica stones, and there will be relatively less insulation materials.
4. Great Wall Dayu Battery
Technical features: Dissipate heat through "drainage"
Battery energy density: None
Compared with the previous batteries that have entered the state of being installed in vehicles, Great Wall's Dayu battery is progressing slightly slower. According to Great Wall officials, this battery will not be officially installed in vehicles until 2022. Although it takes a long time, this battery designed based on the ternary 811 high-nickel battery cell is still very promising.
According to the "Safety Requirements for Power Batteries for Electric Vehicles", Dayu Battery adopts a heating trigger method for the Sanyuan 811 high-nickel large-capacity battery core. The battery core is triggered in the middle of the module, with a temperature as high as 1037 degrees Celsius and an instantaneous air pressure. Under the condition of 16kpa, the smoke exclusion temperature is lower than 100 degrees Celsius, and there is no open flame spillage or explosion.
The reason why this Dayu battery does not catch fire even at a high temperature of 1037 degrees Celsius and an instantaneous air pressure of 16kpa is mainly because it focuses on drainage. In terms of technical solutions, there are four "secrets": 1) Heat source isolation: adopt double protection, use double-layer insulation composite materials between cells, and use high-temperature insulation composite materials between modules; 2) Two-way commutation and heat flow distribution, through The design and simulation of the flow converter channel realizes the control and distribution of the heat source trajectory; 3) Directional explosive discharge, automatic fire extinguishing and positive pressure oxygen barrier, through shunting, diversion and commutation, the fire source is quickly guided to the fire extinguishing channel and discharged. 4) High-temperature insulation and intelligent cooling to prevent high-voltage arcing and inhibit heat diffusion.
To understand simply, it means that by rationally guiding the heat trajectory and combining it with the cooling system, it can achieve the effect of preventing fire and explosion.
In addition to not catching fire, it is worth mentioning that Great Wall Motors’ Dayu battery will open its patents for free. It is reported that Dayu battery technology will be fully applied to Great Wall Motors' new energy series models in 2022. The first project will be the first model of the Salon brand (Great Wall's high-end sub-brand).
The only pity is that currently no finished product of Dayu battery has been released, and the experimental video has not been released. Perhaps only after the actual mass-produced product has been tested, can everyone further understand its strength.
Written at the end
In addition to the "non-fire" batteries developed by the above-mentioned car companies, some battery manufacturers have also launched these batteries, such as the No. 1 battery released by Honeycomb Energy. "Jelly batteries" that can catch fire and heal themselves; in December last year, Sunwanda publicly displayed self-developed power batteries that emit smoke and do not catch fire.