What are the technical reasons for three-dimensional lithium-ion battery frequent burning?

　　Author ：Iflowpower – Portable Power Station Supplier

Tesla used a three-yuan lithium-ion battery. After last year, more than 10 cars had a fire burning accident. In May this year, there were 4 cars in May, resulting in 3 deaths and 1 injuries.

From January to June this year, there were 6 spontaneous fire accidents in foreign new energy vehicles. The three-dimensional lithium-ion batteries used by these vehicles were self-name, and the production process should be not a matter of impact. The accident caused by a serious collision, and she was ignited without reason, which had to find the original from the inner unsafe of the three-dimensional ion battery.

The battery pack and fuel tank are the same components containing high-energy substances, which is the material foundation of electric vehicle safety. The electrolyte in the lithium ion battery is formulated with flammable solvents, and the positive electrode oxidant and negative electrode reducing agent are only separated by a micrometer thick diaphragm. This company is a thinner, and the diaphragm used is thinner.

When charging and discharging, there is more heat during the battery, and the heat is more heat during high-magnification. When a certain temperature is reached, the oxidant on the positive electrode is easy to chemically react with the electrolyte, especially the three-yuan material, which will also analyze the ecological oxygen, this is A state in which the oxygen is spurt, it is easy to chemically react with the reducing substance. A large amount of chemical reaction heat causes thermal out of control, there will be a lot of gas, resulting in elevated air pressure, followed by a battery break, burning, explosion and other accidents.

Therefore, the oxidant on the positive electrode is different, and the temperature of the thermal out of control is different. The lower the positive electrode material heat loss temperature, the worse the safety of the battery. Trimer positive battery safety is lower than the lithium iron phosphate ion battery and other batteries.

Since the three-dimensional ion battery has a combustion of three elements, it can also be spontaneous under the conditions of isolation of air, so the three-yuan lithium-ion battery is difficult to extinguish, spread quickly, and it is difficult to escape the rescue. At present, my country's ternary lithium-ion battery acupuncture experiments cannot be completely passed, but they are allowed to use in a passenger car or even in commercial vehicles. According to incomplete statistics, my country's 1 to September this year will reach 21.

These years, the three vertical development routes led by the Ministry of Science and Technology have changed again, and the pure electric vehicle, hybrid vehicle, fuel power lithium battery electric vehicle, to pure electric vehicle, plug-in electric vehicle, fuel power lithium battery electric Car, then go to pure electric car, increased range electric car, fuel power lithium battery electric car. Among them, the hybrid vehicle is approximately doubled to plug-in; after about 5 years, this year is changed to the extension; always constant is the pure electric car and fuel power lithium battery electric vehicle. At present, there are many problems of fuel-powered lithium batteries to handle, and they are still far from marketization.

Pure electric cars are focused, but long mileage pure electric vehicles under high subsidies need to deal with five anxiety. First, mileage anxiety: even if there is a multi-battery battery, there is a power off; the body is heavy, no power; the air conditioner is seriously shortened. Second, safety anxiety: the battery is much higher, the energy is high, the danger is large, and the combustion explosion occurs.

Third, charging anxiety: charging piles should be intensive, costly, and Fei also difficult to meet the requirements. The fourth is the price anxiety: the battery is large, the price is high, and the competitiveness is low. Fifth, battery anxiety: battery life is shorter than the whole vehicle, second, three batteries to pay for users.

After the subsidy is stopped, the longer the mileage, the more the original subsidy is, the more difficult to sell it. At present, there is only a small electric vehicle that is small, safe and mileage contradictory. Pure electric car pursues long miles, leading to excessive multi-fitting batteries, safety declines, this technology development route is the original fever car.

3. Tenjin subsidy long mileage pure electric car is the policy of frequent burning vehicles. It is caused by electric vehicle mileage indicators and subsidies to hooks with pure electric miles.

The amount of battery nickel is increasing, and the ratio of nickel-cobalt manganese is gradually towed from 333, 523, 622 to 811, and the higher the energy density, the greater the danger. The unreasonable subsidy policy is the original fever. 4.

Mileage as a contradiction is the ideological method of frequent burning cars. It is a matter of safety and mileage. The mileage is considered to be a contradictory, security is considered a secondary aspect of the contradiction, which is the mistake of ideological methods, which is the root cause of development routes, policies, and technology.

In summary, my country's new energy vehicle development routes and policies are misleading, urgent use of three-dimensional lithium-ion battery, excorging the contradiction between safety and mileage, followed by electric car burning events frequently. Moreover, the body is heavy, the power consumption, the actual discharge is high, and the original intention of electric vehicle energy saving and emission reduction. Use the extension technology to handle security and mileage contradictions in the past ten years, the author's claim can be concatenated as two sentences.

Principle: Using safe and mature batteries, develop electric vehicles for energy conservation and emission reduction; technical routes: with minimal pure electric vehicles Break-break, large and medium-sized vehicles develop pure electric drive increase. Tiny pure electric vehicles can be used for lead-acid batteries, or use lithium-ion batteries to do high-speed vehicles, by market decision; increased motor vehicles can handle five major anxiety of pure electric vehicles, marketization is the most feasible. It is gratifying that the author's claim is gradually accepted.

The Ministry of Science and Technology included the increase in the new three vertical lines in January this year; the National Development and Reform Commission was included in the extensive electric vehicle in the "Automotive Industry Investment Management Regulations (Draft for Comments)" released in July. Once the new energy car subsidies are stopped, after the industry enters the market, it is expected that small pure electric vehicles and increased-raising electric vehicles will grow rapidly. The author will divide the development of the increased range into the three generations.

The first generation of the extension electric vehicle is installed in the pure electric car, which is simply for new driving mileage, and is used to power generation by the extension. Take the BMW I3 as an example, such as the installation of the extension, increase the price of 15%, 0.7L displacement engine, and the vehicle is 5.

35L. The small car battery is heavy, the increase in the power is high, energy consumption, and the increase in power generation and battery are simple in series, so the fuel consumption is high. The second generation of increased range electric vehicles optimizes the power system, the engine is reduced, the engine energy efficiency is optimized, the battery is small and the cost is reduced, and the vehicle is reduced to more energy saving.

Its advantage is that the battery pack does not exceed the charge and overhang, the life is prolonged, the safety is high; the lithium phosphate ion battery is suitable, the safety is further improved; the battery is small, the subsidy is small; During driving, more than 50% of the fuel truck is saved; it can be saved; it can be charged, exempt to build charging piles, can drive long distances; if there is charging conditions, the city's 100-kilometer oil rate is more than 80%; Easy to develop and refueling along the fuel car, easy to develop; no mileage, safety, charging, price, battery five anxiety. The second generation of increased range is the fusion of fuel vehicles and electric vehicles, which changed the limitations of the first generation of simple extended renewal mileage, achieving energy conservation and emission reduction. This technology has been used in a variety of vehicles, such as Huanglong New Energy Automotive Co.

, Ltd. 12 meters reunable passenger car, using lithium iron phosphate ion battery, urban bus mode 100 kilometers fuel consumption 12L, highway mode 100 kilometers fuel consumption 16.3L; Canada Planb The increased range truck can reduce 70% pollutant emissions, 100 kilometers fuel consumption 17L; Nissan car Note's E-POWER power system belongs to series hybrid, using three-cylinder 1.

5KWh, battery 1.5KWh, 100 kilometers fuel consumption only 2.9 L; Shandong Dezhou Fu Road Group's increased range low-speed car, lead-acid battery, single cylinder 0.

2L engine, oil electricity efficiency 299g / (kWh), 100 kilometers fuel consumption only 1.8L. However, the second generation of increased range electric vehicles are charged with the battery, and the battery is powered by electricity, and the current flows through the battery pack, so there is also a deficiency.

First, the battery charging-discharge process is at least 10% loss during the discharge; the second is that the battery dosage is less than the pure electric car, but due to the power to meet the maximum speed requirements, the battery usage still needs to be about 40% of the pure electric car, the price is clear 3. It is higher than the fuel car; the third is more battery, the body is heavy, there is weight loss energy saving potential; four is that the battery has always been high load, life is affected. .