AutoBeta(AutoBeta.net)04/22 Report--

New energy vehicles have been paid attention to and favored since they were put on the market, and many manufacturers have sounded the charge in the development of new energy vehicles, while the advantages of new energy vehicles in terms of environment and maintenance are much less worrying than traditional fuel vehicles. However, in August last year, an accident of spontaneous combustion occurred at the EX5pro Automobile Research Institute, but fortunately there were no casualties, but at 23:38 on April 21, Weibo revealed that in the underground parking garage of a residential area in Shanghai's Xuhui District, a Weima car smoked and caught fire, and firefighters were unable to enter the fire scene due to too much smoke in the basement. Only water can be filled in the garage. Tesla officially said that he rushed to the scene as soon as possible.

Famous American actor mary McCormack posted on the social networking site that her husband Tesla modelS spontaneously ignited on the way. Fortunately, someone witnessed and reminded him that he only saw it after he stopped the car. After the Los Angeles police arrived at the scene, it was confirmed that a Tesla ModelS caught fire. Firefighters immediately put out the fire when they arrived at the scene.

We all wonder if we are sitting in a huge explosive bag or a car on top of a new energy model. We can start with the batteries of today's new energy models. Ferdinand Porsche, the man who first built the first electric car, launched a lohner porsche electric car with a wheel housing motor in 1900, which uses an one-ton lead-acid battery with a maximum horsepower of 3 horsepower. Today, the battery used by Tesla, which we focus on, is a 18650 nickel cobalt lithium battery provided by Panasonic. Tesla formed a battery pack by connecting 8000 18650 batteries in series. The energy density of this material is 20% higher than that of ordinary lithium cobalt batteries, but its thermal stability is worse, which means there is a greater risk of thermal runaway and fire. In order to control these unstable batteries out of control, Tesla uses an external fuse (whenever a battery with excessive current is encountered, the battery is disconnected in the case of battery displacement) and by using external liquid cooling to further reduce battery runaway in a large area of the battery. It is worth noting that this is only a single battery that does not spread to other batteries around it. Now we have to worry about the chances of these fires, which makes people feel like sitting in Tesla like the cat in Schrodinger's cat experiment.

What we notice is that the lithium battery used in the model that caught fire is lithium nickel cobalt battery, including the lithium cobalt battery in Weima fire, but our other domestic manufacturer, BYD, uses lithium iron phosphate, and the high temperature resistance of lithium iron phosphate is 300-500 degrees. Compared with the chemical characteristics of the above two batteries, they are relatively less active, so they are relatively at ease. However, most of the batteries made by the battery manufacturers that are mainly supplied in China are mainly ternary batteries, so many of our consumers will worry about when we can get into safe new energy vehicles. The answer is yes, except for traditional chemical battery models. We also have fuel cell models. In this regard, the Japanese manufacturers Toyota and Honda hydrogenated fuel cells are the most advanced, not only with zero emissions. And fuel cells do not have to worry about secondary pollution in recycling. The technical difficulties lie in the construction of hydrogenation stations and the storage of liquid hydrogen. There is also graphene, a chemically stable material with large energy storage, but graphene has not been put into use in mass production because of its high price.

I believe that in the future we can see more and safer new energy models appear and serve our travel.

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