The question of battery life under the advancement of supercharging technology
2025 is considered the “first year of the super-fast charging explosion”. In the past two years, the rapid development of fast charging and super charging has brought convenience to consumers and alleviated the anxiety of driving range to a great extent. But at the same time, the hidden worries behind technological progress also trouble consumers. Fast charging damages the battery, and the battery cost remains high, making consumers love and fear fast charging and super charging. Some analysts pointed out that if the number of fast charging exceeds a certain number, the battery life will be directly “cut in half”. Recently, during the 2025 Shanghai Auto Show, Li Bin, founder, chairman and CEO of NIO, also pointed this out in an interview. He said that if super charging is often used, whether manufacturers can provide 8 years, 10 years or even longer battery warranties remains to be verified.
Ultra-fast charging accelerates battery degradation
The reporter interviewed several consumers about the impact of ultra-fast charging on batteries. Although everyone has no clear understanding of the extent to which ultra-fast charging affects battery life, it is generally believed that just like mobile phones, ultra-fast charging will definitely shorten battery life.
“Although I don’t know the specific values of battery attenuation under ultra-fast charging and slow charging, I think the battery of an electric car is like a mobile phone battery. Using ultra-fast charging should accelerate battery aging.” Beijing electric car owner Zhang Feng told reporters that he once asked the dealer about the cost of replacing the car battery, and the answer he got was almost half the price of a new car. For car owners, whether to choose to replace the battery or buy a new car after the battery has rapidly attenuated is a difficult problem.
Car owner Dong Lin told reporters that using super-fast charging has become a “standard feature” for the fast-paced work and life of “office workers” in the city. Now there are super-charging piles not only in residential areas, but also in cities. He uses super-fast charging hundreds of times a year on average. In his opinion, super-fast charging will definitely shorten the life of the car’s power battery.
Mr. Huang, an online car-hailing driver, said that online car-hailing drivers generally choose superfast charging, and the emergence of superfast charging has indeed saved them a lot of time. However, they found that superfast charging “hurts the battery” and will accelerate the “aging” of the power battery. A recent survey showed that among online car-hailing drivers with an average daily mileage of more than 100 kilometers of pure electric vehicles, the proportion of superfast charging used reached more than 70%, and the health of their on-board power batteries would drop from 100% of new cars to 85% within two years, with an average annual decline of 7.5%.
Lu Chihua, a professor at the School of Automotive Engineering at Wuhan University of Technology, pointed out that according to the current mainstream technical analysis in the industry, the cycle life of on-board lithium iron phosphate batteries can reach 3,000 to 5,000 times, and the cycle life of ternary lithium batteries can reach more than 2,000 times. Based on the charging frequency of 1 to 2 times a week, and considering the life of the battery itself, the power battery can be used normally for 8 to 10 years without any problems. However, frequent use of ultra-fast charging is another matter. Experiments have shown that the battery health of pure electric vehicles with a two-year age and more than 100 fast charges is about 85%, and the decay rate is accelerating. The latest research by the team of Academician Ouyang Minggao of Tsinghua University shows that batteries that frequently use ultra-charges of more than 120kW will have a cycle life that is 40% shorter than slow charging.
There is a “trick” behind the long battery warranty
Regarding the warranty of electric vehicle power batteries, according to the regulations issued by the Ministry of Industry and Information Technology and other departments in 2015, new energy vehicle companies must provide a warranty period of at least 8 years or 120,000 kilometers for batteries and other core components starting from 2016. This means that the warranty period is based on the condition that is reached first, that is, the warranty period ends after the battery is used normally for 8 years or the vehicle has traveled 120,000 kilometers.
It is understood that at present, most car companies also implement the above regulations for the warranty of power batteries, that is, after the power battery has been used normally for 8 years or the vehicle has traveled 120,000 kilometers, the power battery will decay to 70%~80%, and then the replacement conditions can be met. For example, Tesla stipulates that the warranty period for batteries and drive units is 8 years or 240,000 kilometers, whichever comes first. Specifically, the battery and drive unit of Tesla Model S enjoy an 8-year or 240,000-kilometer warranty service, while the warranty period for the whole vehicle and battery drive unit is 4 years or 80,000 kilometers respectively. In addition, Tesla’s battery warranty policy also includes that the battery capacity must be maintained at a minimum of 70% during the warranty period. If the battery decays by more than 30% under normal use, Tesla will provide free battery replacement service.
Under normal circumstances, car owners can choose to replace the battery after the attenuation value of the on-board battery meets the requirements of the car company. However, in reality, the cost of replacing the on-board power battery is usually high and may account for a large proportion of the total price of the vehicle. For example, the battery pack price of a certain brand of electric car priced at 250,000 yuan is 118,000 yuan, and the battery price accounts for more than 40%. Recently, an electric car owner in Zhejiang published his electric car battery replacement quotation on the Internet, which amounted to more than 200,000 yuan. This “sky-high” bill reveals a disturbing fact that the replacement cost of brand batteries and related accessories actually exceeds the residual value of the vehicle itself, which makes some electric car owners exclaim that “replacing the battery is more expensive than changing the car.”
In addition, it is reported that the battery warranty policy provided by some electric vehicle brands includes lifetime warranty for the three-electric system (power battery, drive motor, and electronic control system), but some conditions need to be met, such as the first owner, no more than 30,000 kilometers of mileage per year, maintenance at officially authorized service stores, non-operational use, etc. Only when these conditions are met can the battery be replaced when it decays to 70%~80%.
“Although the power battery warranty policies of car companies can basically comply with national regulations, there are still some brands of ‘routine warranty’ that deceive consumers and ‘dig holes’ for consumers.” Dong Lin told reporters that in one case, some car companies exclude power batteries with more than 200 super-fast charging times per year from long-term warranty, which actually forms a warranty “barrier” for some private cars and online car-hailing users who use more super-fast charging; in another case, although some car companies claim that electric vehicles have a “lifetime warranty”, it does not include “lifetime free battery replacement”. Some brands’ warranties only cover quality issues of the product itself, and do not include normal battery attenuation. If consumers do not pay attention or understand, it is easy to have misunderstandings and illusions that “the battery has a long-term warranty”. In addition, some electric vehicle brands need to go to the agency designated by the car company for identification of the detection value of battery attenuation. The brand does not recognize the values detected by the owner at non-designated agencies, which greatly reduces the long-term warranty of the battery.
Survey data shows that only about 23% of electric car owners fully understand the warranty details, and more than half of the owners mistakenly believe that the “lifetime warranty” covers free replacement of the battery throughout its life cycle. Previously, some electric car brands promised a lifetime warranty on the battery cells, but the battery pack casing, circuit board and labor costs had to be borne by the user. The single cost of these additional costs was at least about 3,000 to 5,000 yuan. Zhang Feng said that some car companies listed “non-first owner”, “third-party repairs” and “battery attenuation less than 80%” as warranty exemption clauses, resulting in a serious reduction in the actual coverage of warranty rights and interests, which harmed the rights and interests of consumers.
Balancing speed and longevity
How to extend battery life and balance battery protection with the protection of car owners’ rights and interests has become a new topic as ultra-fast charging is rapidly becoming popular.
In fact, the industry and enterprises have not ignored this problem. It is one of the consensus of the industry to “prescribe the right medicine” and protect the battery through technological progress. In recent years, many companies have also developed corresponding battery protection technologies for related issues that affect battery life caused by ultra-fast charging. Among them, in terms of controlling the temperature rise of battery charging, some battery companies use the integrated design of water cooling plates to control the temperature difference of the battery cells during fast charging to ±2°C, and cooperate with new electrolytes to make the number of 4C charging cycles exceed 1,500 times, an increase of 50% over traditional solutions. In terms of battery thermal management systems (BMS), some car companies have added a “supercharge protection mode” to limit the charging power to 60kW when the power is less than 20%, avoiding some problems that damage the battery. Others use battery preheating technology to increase the fast charging efficiency by 35% in a -10°C environment, while reducing the battery attenuation rate by 30%.
In addition to the protection of power battery technology, some smart super charging piles today will also automatically regulate the current during the entire charging process to reduce the impact on the battery itself. For example, in the early stages of super charging for electric vehicles, the current is usually large to quickly replenish the power; but as the battery approaches full charge, the current will gradually decrease to prevent overcharging and protect the battery.
“Occasional fast charging has limited impact on battery health.” Qi Lu, director and professor of the New Energy Materials and Technology Laboratory of Peking University, said that while car companies are improving relevant technical measures, they should also popularize the knowledge of scientific and reasonable use of super-fast charging to car owners and consumers. Under normal circumstances, car owners should control the proportion of super-fast charging to less than 40%, and try to use slow charging when time permits, especially to avoid using super-fast charging when the power is less than 10% or more than 90%, because using super-fast charging in this range will cause greater damage to the battery.
Some experts also suggested that through innovation in commercial models, such as adopting a battery leasing model, automakers can be encouraged to shift from “selling products” to “selling services”. The vehicle-battery separation model can reduce users’ sensitivity to battery warranty, while also forcing companies to improve the maturity of fast charging technology.
“In fact, the ultra-fast charging mode not only brings users’ demand for long-term battery warranty, but its essence reflects the dynamic balance between technological progress and user expectations.” Li Ming, vice president and professor of the School of Automotive Engineering of Jilin University, believes that this requires the construction of a balanced system of “technical guarantee-scientific use-policy guidance”. On the technical side, a dynamic power regulation system of “intelligent fast charging protection network” is constructed to monitor the temperature and state of charge of the battery cell in real time through the battery management system (BMS) to avoid overcharging damage. On the user side, a “scenario-based charging” cognitive system is constructed, and even the “emergency fast charging mode” and “daily slow charging mode” developed by car companies can be combined, and consumers can form good usage habits to protect the battery. On the policy side, the “fast charging warranty boundary” is delineated, ultra-fast charging warranty specifications are issued, corporate responsibilities are clarified, and consumers’ worries are eliminated. In this way, it is possible to gradually form a new pattern of “ultra-fast charging + long warranty”, so that the “10-year battery worry-free” of electric vehicles can truly become a reality from a marketing slogan.
Zhao Jianguo Editor: Sun Huanyu Layout: Li Peiyang
Research from Tsinghua University shows that batteries frequently using ultra-charging above 120kW can shorten their cycle life by 40% compared to slow charging. View the full report below.
Sources: ScienceDirect, Netease, New Energy Vehicle News NES, NetEase News and CarNewsChina