The internal resistance of lithium battery is one of the important indicators to measure the performance of the battery, which has an important impact on the charging and discharging process, cycle life and safety of the battery. So, what are the specific functions of lithium battery internal resistance?
1.Affect the charging efficiency: The internal resistance of the lithium battery directly affects the charging efficiency of the battery. The greater the internal resistance, the more heat is generated during charging, which causes the battery temperature to rise. High temperatures will accelerate the aging of the battery and reduce the life of the battery. At the same time, the high internal resistance will also make the voltage drop faster during the charging process, which will affect the charging effect.
2.Affect the discharge performance: The internal resistance of the lithium battery will also affect the discharge performance of the battery. During the discharge process of a battery with a large internal resistance, the current output will be limited, resulting in a decrease in the discharge capacity of the battery. This means that under the same load conditions, the battery with a large internal resistance may not be able to provide sufficient power output, which will affect the normal operation of the device.
3.Affect the cycle life: During the charging and discharging process of lithium battery, the internal resistance will produce a certain amount of energy loss. This energy loss causes the temperature inside the battery to rise, which affects the structural and chemical stability of the battery material. The cycle life of a battery that has been in a high temperature state for a long time will be greatly shortened. Therefore, reducing the internal resistance of the battery helps to improve the cycle life of the battery.
4.Affect safety: When the internal resistance of lithium battery is too large, it may cause the heat inside the battery to be unable to be dissipated in time, resulting in thermal runaway. Thermal runaway refers to the rapid increase in the internal temperature of the battery, resulting in the decomposition and combustion of the battery material. Therefore, controlling the internal resistance of lithium batteries is one of the key factors to ensure the safe use of batteries.
5.Affect the power density: The magnitude of the internal resistance of the lithium battery directly affects the power density of the battery. Power density refers to the maximum power that a battery can output in a certain volume and weight. Batteries with higher internal resistance have a lower power density and cannot meet the needs of high-power devices. Therefore, reducing the internal resistance of lithium batteries can help improve the power density of batteries and meet the needs of high-power equipment.
In summary, the internal resistance of lithium battery has an important impact on the charging efficiency, discharge performance, cycle life, safety and power density of the battery. Therefore, in the process of design, manufacture and use of lithium batteries, attention should be paid to the control and management of internal resistance to improve the overall performance of the battery.
Kunpeng Project