Battery problem is the biggest obstacle to the industrialization of electric vehicles

If electric vehicles can be industrialized, it is of course beneficial to solve the current energy and environmental problems caused by the rapid growth of car ownership. However, several roads on the road to the industrialization of electric vehicles have made us think that it is not easy for electric cars to say "I love you." If we carefully analyze the problems that hinder the industrialization of electric vehicles, we can also find that the battery problem is a difficult problem. As long as the battery problem can be solved, other problems can be resolved quickly. From the current state of development of electric vehicle batteries, there are mainly the following problems.

One is that compared to diesel engines and automobile engines, the cost of the battery is too high.

Bosch on June 16 this year released the current North American market comparison of the cost of diesel engine technology, gasoline engine technology and electric vehicle technology for every 100 miles required. From the figure below, the current use of electric vehicle technology costs a lot more than the traditional car engine and diesel engine technology. In the use of electric vehicles, the cost of the battery occupies a large proportion.

If you want to achieve the industrialization of electric vehicles, you must reduce the cost of electric vehicles to a lower level than traditional gasoline and diesel vehicles. As shown in the figure below, under the premise that this goal can be achieved by 2020, fuel prices must increase by 230% and the cost of batteries must drop by 70%, based on the current US fuel prices. For the next 10 years, whether it is fuel price increase of 230% or battery cost reduction of 70%, it is more difficult to achieve.

At present, the energy density of mainstream lead-acid or iron-iron batteries can only reach a level of 0.1 deg/kg. If one kWh of electricity is equivalent to 0.112 liters of gasoline energy, which is calculated by consuming 15 degrees of electrical energy per 100 kilometers, the mileage of an electric vehicle with a mileage of 500 kilometers will only reach 750 kilograms. According to the industry-recognized cost price of 1000 US dollars/degree, the battery cost of an electric vehicle should be close to 80,000 US dollars in order to achieve the cruising range of ordinary internal-combustion engine cars. (Remarks: The current international use of batteries for pure electric vehicles. The immediate goal is to weigh less than 250 kilograms, with a peak power of 100 kilowatts, a power density of 400 watts per kilogram, an energy of 40 kilowatt-hours, and a charge of about 270 kilometers.

Second, the problem of battery quality consistency cannot be effectively solved in the short term

Since the traditional automobile engine has undergone continuous improvement for nearly a century, its reliability and durability have reached a very high level. However, the battery of an electric car has not passed such a large-scale, long-term and various conditions of environmental testing. In particular, in the quality problems faced by batteries, quality consistency issues are the key. Because the electric car battery is composed of many small battery packs. If the texture of the raw materials used by each small battery pack or its manufacturing process is inconsistent, there will be a difference between each small battery, and eventually the consistency of the entire vehicle battery quality cannot be guaranteed.

Taking a lithium battery as an example, overcharging and overdischarging of a lithium battery are not easy to control. For single-cell lithium batteries, both overcharging and overdischarging are easy to control, but the lithium batteries used in electric vehicles are made up of several small lithium batteries connected in parallel, as long as the consistency of these small lithium batteries. Bad, it is easy to cause some overcharge, some underfill phenomenon, and ultimately affect the battery life and cost.

Third, the battery life is too short

At present, all electric vehicle batteries have long-lived problems. In general, the battery should be replaced at least once during the entire life cycle of the electric vehicle, that is, about once every five years or so. However, the longest warranty/replacement that auto companies can provide is only about two years. What's more, the more intractable, the faster or shorter the charging time of a typical vehicle battery, the shorter its life expectancy. In other words, prolonging battery life and realizing battery's rapid charging function are still a paradoxical problem. (Note: In order to solve the cost, life, and quality problems of vehicle batteries, there is currently a kind of “naked car sales, battery rental” in the industry. The concept of a business model of “rechargeable, compatible, smart management, and credit card consumption” means that future users will not need to purchase batteries when they purchase electric vehicles, but can purchase different types of electric vehicles at the same or less expensive cost than fuel vehicles. The battery used in the electric vehicle is purchased by the power station, and it is jointly provided with the insurance company to provide battery rental service for the electric vehicle user with ultra-low rental fees. After the user purchases the electric vehicle, he can apply for the battery rental procedure, and only need to pay the battery composition. -20% deposit and payment of battery insurance premiums to insurance companies on a yearly basis will qualify for access to the network and lifelong use of the battery until the vehicle is scrapped.

In fact, in addition to the battery cost, life, and quality issues described above, the battery charging time is too long and the mileage that a charge can run is too short to be a problem to be solved. Therefore, before the technology has not reached a certain practical standard, it is easier to achieve industrialization of electric vehicles.