Three reasons why the power battery limits the depth of discharge

There are three important reasons why power lithium-ion batteries limit the depth of discharge. In fact, any electric vehicle that uses lithium batteries has a rule that the full capacity of the battery cannot be used for travel, and only a few kilowatt-hours are left to buffer the battery. For example, 60kwh (55kwh available) may appear in the standard format or other similar regulations. If you are satisfied with this, you will find that any electric vehicle that uses lithium batteries has a rule, that is, you cannot use the full capacity of the battery for travel, and always set aside a few kilowatt-hours to buffer the battery. For example, 60kwh (55kwh available) may appear in the standard format or other similar regulations. Three important reasons for power lithium-ion batteries to limit the depth of discharge In fact, there are three important reasons for limiting the depth of discharge of lithium batteries. The first reason is that the cycle life increases dramatically as the depth of discharge (DoD) decreases. Technically speaking, it is quite difficult to reduce the impact of battery charging and discharging at the deep drop point on the cycle life, which depends on many factors beyond the control ability of the existing technology. A very typical example is the Winston battery 100AhLFP battery standard meter, the battery life is 5000 cycles, according to the Ministry of Defense 80%, 7000 cycles, according to the Ministry of Defense 70%. This shows the impact of depth of discharge on battery life. The second reason is that when the battery dispenses any electrical current, the internal resistance of the battery increases as the capacity decreases. When the depth of discharge is large, the resistance increases when the current is stable, which requires the battery to supply more energy and waste electrical energy in the form of heat. The third reason is that when the depth of discharge is large, the original stable discharge curve of the battery will change sharply. Therefore, by limiting the depth of discharge to a relatively flat range, customers can better control the power and get a better application experience. It is worth mentioning that the depth of discharge of the shackle is not the same concept as the discharge capacity of the battery. For example, the 60 and 70 kWh batteries of the Tesla Model S can be upgraded through software to unlock the rated battery capacity to 75 kWh. After the upgrade, ModelS still has a good battery capacity as a safety buffer. So the question is, will the missing 60Kwh battery of ModelS have a longer life? Statement: Some pictures and content of the articles published on this site are from the Internet. If there is any infringement, please contact to delete. Previous: Analysis of the types of battery explosions