According to relevant news, Toyota will launch a solid-state battery within this year, which can provide 500 kilometers of driving range. According to Toyota officials, this solid-state battery is expected to become a viable alternative to liquid electrolyte lithium batteries. The battery can be charged from empty to fully charged in 10 minutes. The charging speed is close to that of refueling a traditional fuel vehicle, and it only has a very limited charge. Minor safety hazard.
In terms of supporting new energy vehicles, although Toyota will announce the solid-state battery within this year, the prototype vehicle equipped with the solid-state battery will not be launched until 2022, and according to Toyota’s plan, its Mass production will take place around 2025. In the field of solid-state batteries, Toyota Motor has a globally recognized leading advantage. Public information shows that Toyota currently has more than 1,000 solid-state battery-related patents.
In fact, compared with the liquid lithium batteries we use now, car companies have already been involved in the development of solid-state batteries, trying to overcome the current problems faced by liquid lithium batteries in another unique form. Therefore, solid-state batteries The battery is also recognized as the next generation of power batteries and may replace liquid electrolyte lithium-ion batteries. At present, many related companies, including CATL, BYD, Guoxuan High-tech, etc., claim to have in-depth research in this field, and even many companies and universities have participated in the research and development of solid-state batteries, such as Daimler, Fisker, Chinese lithium battery giant, French oil company Total and spin-offs from MIT and Stanford University.
In terms of development prospects, solid-state batteries seem to be very attractive, but from an application perspective, are solid-state batteries really the most suitable energy carrier for electric vehicles? And if solid-state batteries really become popular, can they bring about a real explosive era for electric vehicles?
The most obvious shortcomings of the liquid electrolyte lithium batteries we can see today are the safety hazards caused by instability and the obvious impact of performance degradation on driving in different environments. , such as battery self-ignition and sharp decline in battery life in winter, are the core problems currently faced by liquid electrolyte lithium batteries. The advantage of solid-state batteries is to fill in these shortcomings of liquid batteries.
We generally see spontaneous combustion in electric vehicles that occurs during charging. The main reason why this problem occurs is because the growth of lithium dendrites during the charging process of liquid electrolyte batteries can easily pierce the separator. Causes a short circuit in the battery, causing unstable changes in the internal structure of the battery, leading to spontaneous combustion. Moreover, based on the motion characteristics of the electrolyte, in a low-temperature environment, the viscosity of the electrolyte will increase and the ion conduction speed will slow down, resulting in a mismatch in the electron migration speed of the external circuit. Therefore, the battery will be severely polarized and the charge and discharge capacity will decrease sharply. This That is why electric vehicles suffer serious power loss in extremely cold areas.
In contrast, solid-state batteries do not have the above-mentioned troubles of liquid batteries, mainly because the structure of solid-state batteries is essentially different from liquid batteries. The two ends of a traditional lithium battery are the positive and negative poles of the battery, and the electrolyte (liquid state) is in the middle. During the movement of lithium ions from the positive electrode to the negative electrode and then to the positive electrode, the charging and discharging process of the battery is completed. Solid-state batteries are batteries that use solid electrodes and solid electrolytes, which can inhibit lithium dendrites, are not easy to burn, are not easy to explode, have no electrolyte leakage, and will not cause side reactions at high temperatures, etc. This means that solid-state batteries can be perfect Avoid the characteristics of liquid electrolytes and become a safer capacitor carrier.
And the energy density of solid-state batteries is higher. For ordinary liquid batteries, it can generally reach 300Wh/kg, which is the highest, but exceeding 500Wh/kg is considered impossible. Solid-state batteries do not need to use lithium-embedded graphite negative electrodes, but can directly use metallic lithium as the negative electrode. This can greatly reduce the amount of negative electrode material and significantly improve the energy density of the entire battery. The energy density that solid-state battery research and development can provide can basically reach 300-400Wh/kg. The starting point is the end point of liquid batteries. It can be said that it has considerable development potential. For this reason, solid-state batteries are also considered to be the key to electric vehicles. Ideal battery.
Compared with the shortcomings in performance, the reason why solid-state batteries need to enter the market as soon as possible is to fill another major problem of liquid electrolyte lithium batteries - lifespan. According to data from the China Automotive Technology and Research Center, the cumulative number of retired power batteries in China in 2020 will exceed 200,000 tons. If these lithium batteries are not handled properly, they will cause environmental pollution for up to 50 years.
At this time, two very important issues will arise. First, as electric vehicles continue to circulate on the market, the market share of liquid electrolyte lithium batteries will only continue to increase, and based on their short life (a pure For electric vehicles, it is conservatively estimated that the battery will enter the scrapping stage after it decays below 80% in 5-7 years). The number of retired liquid electrolyte lithium batteries will only increase year by year, and its processing pressure will only increase year by year.
The second is based on the car companies’ recycling capabilities for these liquid electrolyte lithium batteries. Battery recycling needs to be dismantled and renovated and then assembled into new power batteries before they can be reloaded on electric vehicles. In this case, The costs incurred are undoubtedly huge. But of course, some people say that power battery recycling is a new blue ocean derived from electric vehicles. However, if more recyclable solid-state batteries enter the market, the battery life of electric vehicles will be significantly improved (ideally, solid-state batteries are recycled It can reach about 45,000 times.) The blue ocean of power battery recycling may have a big impact.
In fact, in terms of battery characteristics, the various benefits of solid-state batteries are also obvious. The most important thing is that solid-state batteries solve the two core problems of reliability and charging efficiency of today’s electric vehicles. This is also a consumer choice. The core concerns of consumers when choosing electric vehicles. And from the perspective of the underlying cause of battery life anxiety, if Toyota's solid-state battery can really charge the battery from empty to full within 10 minutes, it will basically fill the gap between electric vehicles and fuel vehicles in terms of battery life. This is undoubtedly This is the biggest impact of electric vehicles on fuel vehicles.
And judging from the new energy strategies of various countries around the world, many countries have now put a ban on the sale of fuel vehicles on the agenda. The basic planning time is 2025 (Netherlands, Norway), 2030 (United States) (California), Germany, India) and 2040 (France, the United Kingdom), and Toyota said that solid-state batteries will be used in real vehicles in 2025, and it is also stepping on the earliest ban on the sale of fuel vehicles. Such a It has also smoothly integrated with global automobile development trends.
Whether electric vehicles are good or not is still too early to answer. Because there is still considerable development potential for electric vehicles, which is why new energy vehicles can still attract a large wave of investment and attention even when the technology is not yet fully mature. But it is worth affirming that the new era accompanying new energy vehicles will change the future pattern of the automotive industry. Perhaps the arrival of solid-state batteries will be another opportunity to lead the explosion of this industry.