There are always new energy vehicle owners who reflect:
Why is fast charging getting slower and slower?
Let me tell you about the things behind the "fast and slow charging".
We need to understand the principle of "fast charging". The fast charging of new energy vehicles is achieved by increasing the charging current, but it is not that the larger the charging current, the better. When the charging current is too high, the chemical reaction inside the battery will become violent, producing a large amount of heat energy, which will cause the battery temperature to rise. The battery temperature is too high will affect the service life and safety of the battery, so the vehicle will automatically reduce the charging speed during the charging process to ensure that the temperature of the battery is within a safe range.
In order to protect the safety of the battery and extend the life of the battery, many electronic devices are equipped with a battery management system (BMS). The BMS will monitor and manage the charging and discharging process of the battery to prevent abnormal conditions such as overcharging and overdischarging of the battery. However, in some cases, the BMS may limit the charging current, which can affect the charging speed.
For example, when the battery is close to full charge, the BMS may reduce the charging current to protect the battery from damage. In this case, even with fast charging technology, the charging speed will be slower
We also need to consider the impact of environmental factors on the charging speed. For example, when the temperature is warmer, the battery's ability to dissipate heat decreases, causing the battery temperature to rise faster. At this time, the vehicle will automatically reduce the charging speed in order to protect the safety of the battery.
In the same way, when the temperature is lower, the heat dissipation capacity of the battery will be enhanced, which will increase the charging speed; However, when the temperature is too low, the vehicle will take certain protective measures, such as limiting the charging current, to prevent the battery from being too cold and causing damage.
Of course, in addition to the vehicle-end restrictions, battery materials, battery temperature, charging pile technology, etc. It will also have a certain impact on the charging speed, especially as the weather continues to get cooler, and in some areas with low temperatures, the charging speed will also drop to a certain extent!