Lithium-ion battery pack equalization charging analysis -Lithium - Ion Battery Equipment
Commonly used lithium-ion battery pack balancing charging technologies include constant shunt resistance balancing charging, on-off shunt resistor balancing charging, uniform battery voltage balancing charging, switched capacitor balancing charging, buck converter balancing charging, inductor balancing charging, etc. When a group of lithium-ion batteries is charged in series, each battery should be charged evenly, otherwise the performance and life of the entire battery group will be affected during use.
1. Attach a parallel balancing circuit to each single cell of the lithium-ion battery pack to achieve the purpose of shunting. In this mode, when a battery reaches full charge first, the balancing device prevents it from overcharging and converts excess energy into heat to continue charging the remaining batteries. This method is simple, but it will cause energy loss and is not suitable for fast charging systems.
2. Before charging, discharge each cell one by one through the same load to the same level, and then perform constant current charging to ensure a more accurate equilibrium state between each cell. However, for battery packs, due to physical differences between individuals, it is difficult for each cell to achieve completely consistent ideal effects after deep discharge. Even if the same effect is achieved after discharging, new imbalances will appear during the charging process.(Lithium - Ion Battery Equipment)
3. Test and averagely charge the single cells in the lithium-ion battery pack on time, in sequence, and individually. When charging a lithium-ion battery pack, it can be ensured that each lithium-ion battery in the battery pack will not be overcharged or over-discharged, thus ensuring that each battery in the lithium-ion battery pack is working normally. state.
4. Using the time-sharing principle, through the control and switching of switch components, additional current flows into the battery with a relatively low voltage to achieve the purpose of balanced charging. This method is more efficient, but the control is more complicated.
5. Use the voltage parameters of each battery as the balancing object to restore the voltage of each battery to be consistent. During equalization charging, the capacitor is alternately connected to two adjacent batteries through a control switch, receives charge from the high-voltage battery, and then discharges to the low-voltage battery until the voltages of the two batteries become consistent. This balancing method better solves the problem of battery pack voltage imbalance, but this method is mainly used in situations where the number of batteries is small.
6. The entire system is controlled by a single-chip microcomputer, and each battery has an independent set of modules. The module performs charging management on each single battery according to the set program, and automatically disconnects after charging is completed. This method is relatively simple, but when the number of single cells is large, it will greatly increase the cost and is not conducive to reducing the system volume.
1. Attach a parallel balancing circuit to each single cell of the lithium-ion battery pack to achieve the purpose of shunting. In this mode, when a battery reaches full charge first, the balancing device prevents it from overcharging and converts excess energy into heat to continue charging the remaining batteries. This method is simple, but it will cause energy loss and is not suitable for fast charging systems.
2. Before charging, discharge each cell one by one through the same load to the same level, and then perform constant current charging to ensure a more accurate equilibrium state between each cell. However, for battery packs, due to physical differences between individuals, it is difficult for each cell to achieve completely consistent ideal effects after deep discharge. Even if the same effect is achieved after discharging, new imbalances will appear during the charging process.(Lithium - Ion Battery Equipment)
3. Test and averagely charge the single cells in the lithium-ion battery pack on time, in sequence, and individually. When charging a lithium-ion battery pack, it can be ensured that each lithium-ion battery in the battery pack will not be overcharged or over-discharged, thus ensuring that each battery in the lithium-ion battery pack is working normally. state.
4. Using the time-sharing principle, through the control and switching of switch components, additional current flows into the battery with a relatively low voltage to achieve the purpose of balanced charging. This method is more efficient, but the control is more complicated.
5. Use the voltage parameters of each battery as the balancing object to restore the voltage of each battery to be consistent. During equalization charging, the capacitor is alternately connected to two adjacent batteries through a control switch, receives charge from the high-voltage battery, and then discharges to the low-voltage battery until the voltages of the two batteries become consistent. This balancing method better solves the problem of battery pack voltage imbalance, but this method is mainly used in situations where the number of batteries is small.
6. The entire system is controlled by a single-chip microcomputer, and each battery has an independent set of modules. The module performs charging management on each single battery according to the set program, and automatically disconnects after charging is completed. This method is relatively simple, but when the number of single cells is large, it will greatly increase the cost and is not conducive to reducing the system volume.
