How long is the battery life of an electric car?

"How fast can this electric car run?" "This electric car, change the battery a few years, change tens of thousands of dollars?" The average new energy vehicle users and sales are asked the most, basically these three the problem is, how fast and how far to run is a good solution, basically running a few laps can be estimated. And battery life, but not simply test the car can know. Anyone with a little experience in car maintenance knows that batteries, which are consumable parts of traditional gasoline vehicles, have an average life of about 3 years and need to be replaced when they arrive. A small car battery costs a few hundred dollars, and a few hundred kilograms of batteries on an electric car. Isn't it expensive? After a few years of hard work to save the money, it is not enough to change the battery! There are quite a few people with similar views, and the life expectancy of the reference battery accessories seems to have some truth. So, is the battery of an electric car really unbearable as rumored? Let's start with the type of mainstream battery.

First, the classification of power batteries

The power batteries currently used in automobiles are roughly classified into lead-acid batteries, lithium batteries, and nickel-hydrogen batteries. Among them, nickel-metal hydride batteries are only used in Toyota's non-plug-in hybrid vehicles, which are not suitable as a separate power source; lead-acid batteries are mainly used in low-speed electric vehicles, which is also known as "old man"; lithium batteries are the most widely used electric vehicle power battery. Lithium batteries are divided into many types according to different materials. At present, the mature applications are mainly ternary lithium batteries and lithium iron phosphate batteries. The models that use lithium batteries in the market are basically these two types of batteries.

Second, lead acid may require a dog belt, nickel-hydrogen is a carnival of Toyota alone lithium battery is king!

Let's start with a lead-acid battery. In fact, it is the battery on a general car, and it is directly used as a power source after multiple strings/parallel. This type of battery, the discharge current is small (the result is that we usually say "car is not strong"), the models are not running fast, the fastest speed is about 60 kilometers, the life is also relatively short, the cycle of 3 years or so must be replaced It is. The advantage is that the production threshold is low, the price is cheap, and the requirements for the protection circuit and the equalization circuit are lower, and basically the hand workshop can be produced. Disadvantages, slow speed, low power, short life..... New energy vehicles that meet national requirements do not use lead-acid batteries. However, many of the impressions that such batteries have left in people's minds have been directly transferred to lithium batteries.

How long can an electric car battery last? This is the easiest answer. Two lithium-ion batteries also have different "tempers". Let me talk about ternary lithium batteries. More representative vehicles include Tesla, Beiqi E200EV, Jianghuai IEV5, Chery eQ, etc., characterized by high energy density, large volume under the same volume and weight; good battery consistency and mature production technology. In this type of battery, the theoretical cycle life is about 1500 times. In actual use, the complete charge and discharge cycle is more than 800 times, and the control battery discharge is in the state of 25%-75%, and the actual use can reach more than 1200 times. Seeing here, are you going to say that 800 times, 1 time to charge 1 time, less than 3 years will not work? Here, I would like to explain the concept of a complete loop. Refers to the battery is fully charged then put it out, count a cycle. If you use 75% from 100% every day, then fill it up, then 4 days is a complete cycle, and the life can reach 10 years. With a typical ternary lithium battery electric vehicle running for 200 kilometers, the actual cycle can also travel 180 kilometers in one complete cycle, and 144,000 kilometers in 800 cycles. It is normal attenuation, and there is no pressure on 120,000 kilometers. In the frequency of 60 kilometers per day, it can be used for 10 years. If you pay attention to the shallow charge and maintain the battery, the 1200 cycles, 150,000 kilometers, basically cover the life of the family car, that is, the battery and the car have the same life, no need to replace the battery in the whole cycle.

The battery has the same life as the car, and there is no need to replace the battery during the entire cycle.

Let us talk about lithium iron phosphate battery, representative models are BYD Qin, BYD Tang, BYD E6, Tengshi, Jianghuai IEV4. The characteristics of this type of battery are long cycle life, which can reach 2000 cycles or more; the charge and discharge rate is high, that is, it can have a larger charge and discharge current; the safety is good, and the bending and puncture high temperature are no problem. The disadvantage is that the energy density is lower, the same battery life needs to use more batteries, correspondingly increase the weight and cost; the consistency is worse, need a better battery management system; the low temperature attenuation is more obvious, the capacity will be reduced by 10% at 0 °C Left and right, and the capacity will be reduced by about 30% at -20 degrees.

2000 cycles have been more than enough for pure electric vehicles. Even for Qin, which has only 70 kilometers of battery life, 2000 cycles can support Qin Chundian's driving of 140,000 kilometers. Counting the mileage of using gasoline, it is no problem to cover the life of the whole car.

Third, what if there is a problem?

There may be friends who think that the car is not finished, what should I do if the battery has problems within the life span? Is it costly to repair? First of all, the state now requires that the key components of new energy vehicles (batteries, electric controls, motors) provide no less than five years or 100,000 kilometers of warranty, and since 2016, provide no less than 8 years or 120,000 kilometers of warranty. During this period, repairs are completely free, and some manufacturers offer a longer warranty period than this, such as BYD, battery life warranty. Then, after the insurance, what should I do if the battery fails? Is it necessary to change the battery pack? It really needs to be replaced, but the cost is not tens of thousands of people's hearts, because there is no need to replace the entire battery. Just replace the corresponding piece or pieces of faulty battery. The cost of a single battery is only a few hundred dollars. When it comes to working hours, one or two thousand dollars should be cheaper than fuel truck maintenance. At this point, the worry that there will be high battery replacement costs during the use of electric vehicles can be eliminated. You can choose the new energy car that suits you with confidence. You don't need to pay any extra cost for the battery during the whole process you can enjoy the different experience brought by the new energy car.

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