Active balancing has abandoned the passive balancing method of current consumption and changed to a method of transmitting current. The device responsible for charge transfer is a power converter. This device enables the small batteries in the lithium-ion battery pack to transfer charge regardless of whether they are charged, discharged or idle, so that the small batteries can always maintain dynamic balance.
Because the charge transfer efficiency of the active balancing method is extremely high, it can supply a higher balancing current, which means that this method has a stronger balance ability when charging, discharging and idle lithium-ion battery packs.
1. Strong fast charging ability: The active balance function can make the small batteries in the lithium-ion battery pack reach equilibrium faster, so the safety of fast charging is higher, and it is suitable for higher current high-rate charging methods.
2. When idle: Even if each small battery has reached the equilibrium state during charging, due to the different temperature gradients, the internal temperature of some small batteries is higher, and the internal temperature of some small batteries is lower, which will make the inside of each small battery The leakage rate is different. The test data shows that the leakage rate doubles every time the battery rises by 10°C. The active balance function can ensure that the small batteries in the idle lithium-ion battery pack are constantly rebalanced, which is beneficial to the storage in the battery pack. The power can be fully utilized, so that when the working capacity of the battery pack ends, the residual power of a single small lithium-ion battery is minimized.
3. When discharging: There is no lithium-ion battery pack with a discharge capacity of 100%. This is because the end of the working capacity of a group of lithium-ion batteries is determined by a small lithium-ion battery that is discharged first, and cannot be guaranteed All small lithium-ion batteries can reach full capacity at the same time. On the contrary, there are individual small lithium-ion batteries that retain unused residual power. Through the active balance method, when the lithium-ion battery pack is discharged, the internal large-capacity lithium-ion battery will distribute the electric energy to the small-capacity lithium-ion battery. Therefore, the small-capacity lithium-ion battery can also be fully discharged, and there is no There is residual power left, and the battery pack with active balancing function has a larger actual storage power (that is, it can release power closer to the nominal capacity).