With the popularization of new energy vehicles, more and more people are driving pure electric vehicles to travel in cities. The increase in the number of users has caused the demand for charging piles to rise rapidly, and fast charging has become one of the core needs of many car owners for pure electric vehicles. But in actual use, many car owners are also worried about multi-frequency fast charging, will it speed up the loss of power lithium batteries and reduce their service life? So what is the real situation?
Does frequent fast charging damage the battery life?
Frequent fast charging will have a certain degree of impact on the batteries currently carried in electric vehicles, and the degree of impact varies depending on the type of battery. At present, lithium-ion batteries and lead-acid batteries are commonly used in electric vehicles. Among them, lithium-ion batteries also include iron phosphate lithium-ion batteries and ternary lithium-ion batteries. Different types of batteries need to be analyzed differently.
Lead-acid batteries are currently mainly used in micro-electric vehicles. The general fast charging mode is divided into three stages, constant current, constant voltage, and trickle charging. Because the current and voltage of fast charging are too large, the heating of the battery will inevitably reduce the electrolyte inside the battery, resulting in a reduction in capacity and continuous driving mileage.
Lithium-ion batteries have lighter weight and higher energy density, and are currently commonly used battery products in most electric vehicles. Lithium-ion battery is a device that generates electric energy through chemical reaction. When fast charging, there will be a large current and voltage input in an instant. Frequent use of fast charging will reduce the battery’s reducing ability, thereby reducing the number of cycles of charging and discharging, and causing damage to the battery. Certain damage.
Regarding the lithium iron phosphate battery, the number of cycles will decrease at low temperatures, resulting in a decrease in battery capacity. It has a relatively low density. If fast charging is tantamount to worsening the situation, the driving range will decrease. The low temperature has little effect on the ternary lithium-ion battery. On the contrary, it will exhibit unstable characteristics at high temperature. For example, if a large current input is used when the external temperature exceeds a certain range, it may cause a certain battery in the battery pack. Overheating causes the phenomenon of thermal failure in the long run.
In comparison between the two, in the fast charge mode, the safety of the lithium iron phosphate battery is relatively high. This is due to its lower energy density and less impact on the battery core in the fast charge mode. However, the ternary lithium-ion battery has a smaller volume and a higher density. It is precisely because of its active chemical properties that it is easier to oxidize with oxygen in the air. When the charging temperature is higher than the specified range by a certain percentage, Prone to burning. Therefore, in the fast charge mode, the impact on the core of the ternary lithium-ion battery is greater.
However, pure electric passenger cars are more safe during charging due to the smaller battery size, higher density, and more stringent battery protection and charging safety.
Can fast charging technology completely solve the impact on battery life in the future?
Although fast charging has brought a certain impact on electric vehicle batteries, proper use can still provide car owners with more convenience. At present, the research and development of fast charging technology has become the core of global car companies’ attention.
In the research conducted by technology companies in my country, Europe, America, Israel, etc., the technologies related to improving charging efficiency and battery life are quite intensive. It is reported that a concept car of Porsche, MissionE, uses an 800V charging voltage system, which can charge the vehicle 80% in 15 minutes. Tesla’s super charging station uses only 480V DC in the DC fast charging mode, so it can achieve 80% charging in 40 minutes. Previously, foreign media reported that Toshiba has developed a brand-new fast-charging battery. Researchers claim that it can be fully charged with 90% of the power within 5 minutes, and has a 10-year lifespan and high level of safety. In addition, there is also the latest news that a US company that studies solid-state power said that BMW and Toyota may introduce solid-state battery technology in the future, which can allow electric vehicles to reach or exceed 800 kilometers.
The large-scale popularization of fast charging requires safety issues to be solved first!
Although the market has this urgent demand for fast charging technology, there are still many difficulties in the popularization of high-power fast charging.
First of all, fast charging, as an emerging technology, is applied to the field of electric vehicles. It also faces many bottlenecks. For example, the inconsistent charging interface of vehicle models makes fast charging standards inconsistent. Of course, some foreign brand car companies have begun to follow my country’s standards. For example, Tesla has begun to design models that meet my country’s charging interface standards.
Secondly, my country’s power system more hopes that car owners will charge slowly at night. Some fast charging stations face problems such as difficult access to the site and insufficient capacitance, which may have certain difficulties when they are widely popularized.
Of course, with the popularization of fast charging technology, the more high-current and high-voltage charging and discharging, the more its safety cannot be ignored. While always emphasizing fastness, what should be ensured is the safety of battery use, such as the design and layout of battery packs, etc., through rigorous design to reduce safety problems caused by battery damage.