TW201403994A - Multi-stage battery module charging method and device thereof - Google Patents

Abstract

A multi-stage battery module charging method and a device thereof are disclosed in the present invention. The charging method comprises the following steps of: (a) perform a first-stage charge to the battery module with a first default current; (b) check whether the battery module achieves a default voltage through a judgment unit; (c) perform a second-stage charge to the battery module with a second default current if the default voltage is judged to be achieved; (d) if the default voltage is judged to be achieved again and a default voltage difference among batteries, or one of the batteries exceeds the default voltage, then perform a third-stage charge with a third default current aiming at the batteries with lower voltage; (e) if the default voltage is judged to be achieved again, then perform a fixed-voltage charge on the battery module by the default voltage and the second preset electric current as an initial charging current till the battery module is charged full. Wherein the default voltages are provided by the charger supplier and the judgment unit is a battery management system which connects to both ends of each battery with a switch loop corresponding to each battery. The switch loop is conducted with the charging loop when the battery management system detects the said voltage difference or the default voltage. Such that the current flows through the switch loop to charge the low voltage battery directly. By using the present method, the situations of over-charge or under-charge of partial batteries can be prevented during charge of the battery module, in the meanwhile the voltage can be stabilized, charging efficiency of the batteries can be promoted, and service life of the batteries can be prolonged.

Description

Multi-stage battery module charging method and device thereof

The invention relates to a charging method and device for a battery module, a method and a device for charging a multi-stage battery module capable of adjusting a current direction and charging a battery with a lower voltage.

Traditionally, the battery module is charged by multi-stage charging in the state of a single string battery pack or a battery module. The first phase is constant current charging, and the second phase is constant voltage charging. As shown in the fifth figure, a schematic diagram of a conventional battery charging state is shown. The first stage of the battery (t = t ₀ ~ t ₁ ) performs constant current (I _B ) charging, and the curve (V _PC ) represents the change in the voltage of the battery module. When the voltage of the battery module reaches the voltage (V _inc ) provided by the appliance, it enters the second phase (t=t ₁ ~ t ₂ ) and the voltage is fixed (V _inc ) until the battery module is full (t=t ₂ ). until. This method first provides a certain current to charge the battery module for a period of time to a preset voltage. In the charging process, not only the temperature will rise, but also because the voltage of the battery module is charged, and it is impossible to target each of the batteries. The state of charge is adjusted, but the resistance value and initial voltage of each cell are not necessarily the same. Therefore, during the process of charging the preset voltage, it is possible that the voltage of a certain cell or cell group has exceeded the safe value (ie, each The voltage imbalance between the cells or each cell group can cause the battery module to overheat and affect the life.

In order to solve the above problem, another battery charging state is provided, as shown in the sixth figure. This charging method first measures the maximum voltage and the minimum voltage change of each battery group. The first stage (t=t ₀ ~t ₁ ) is charged with constant current (I _B ). When the maximum voltage (V _emax ) of the _{battery pack} reaches the rated voltage (V _coff ), the charger is turned off, when the battery pack When the maximum voltage drops to the lower voltage limit (V _con ), the charger resumes power supply to the battery pack. When the rated voltage (V _coff ) is reached again, the charger is turned off, and the charger is turned on and off until the cells are charged. Until the battery is fully charged. In the second phase (t=t ₁ ~t ₂ ), the magnitude of the current is determined according to the change of the minimum voltage of the battery group, when the minimum voltage (V _emin ) of the battery group exceeds the voltage (V _inc ) given by the charger. That is, the second stage is gradually adjusted to reduce the magnitude of the charging current, and the power supply is intermittently given as the maximum voltage of the battery pack changes until the battery is full (t=t ₂ ). Although this charging method can balance the voltage between each group of cells (or cells), avoiding the problems of current overcharge, overvoltage, and excessive temperature, but repeatedly switching the charger, frequently charging and discharging the battery will break. Battery life and extend the entire charging time.

The seventh figure provides another charging method, which is to charge the battery module in the first stage (t=t ₀ ~ t ₁ ) with the first preset current (I ₁ ). When the battery module has a battery core, reaches a predetermined voltage (V _1), is changed to be less than a first predetermined current (I ₁₎ of a second predetermined current (I ₂₎ a second charging phase _{(t = t 1 ~ t 2} ), when the battery When the battery core reaches the preset voltage (V ₁ ), the battery is charged with the preset voltage V ₁ until the battery module is fully charged. In this way, the voltage of each cell is controlled to be lower than the preset voltage by adjusting the current, although the voltage of the cell can be prevented from being too large, but the charging of each phase only observes whether or not the cell exceeds the preset voltage. There is no guarantee that each cell will reach the preset voltage and the voltage between the cells will not be balanced.

The Republic of China Patent Publication No. I366322 provides a charging device including a first voltage converter, a second voltage converter and a control module. The first voltage converter outputs power to charge the first energy storage component and the second energy storage component, and the second voltage converter outputs power to charge the second energy storage component. When the second energy storage component is charged to a saturation threshold voltage, the control module controls the second voltage converter to stop charging the second energy storage component, and simultaneously returns the current to be flowed into the second energy storage component to the first voltage The converter performs conversion, and after the first voltage converter is converted, the first energy storage component is charged to reduce the output power of the power supply to achieve energy saving effect. Wherein, the current to flow into the second energy storage component first flows to an inductor, which begins to store energy due to reverse excitation, and after the control module controls the switch, the inductor releases its stored energy and returns The first voltage converter is given for conversion.

Although the above charging device can avoid overcharging of a single energy storage component and can charge an energy storage component with a lower voltage, since the inductance cannot be used to control the flow of excess current, more current can only stop adjacent energy storage. Component, therefore, when the charging device needs to charge a plurality of energy storage components, each energy storage component needs to be equipped with a voltage converter to determine the charging, thereby achieving the purpose of balancing the voltages of the energy storage components.

Accordingly, this charging technology is used for high-power energy storage applications such as electric bicycles (EVs), electric vehicles (EVs) or energy storage devices (ESS) because of the energy storage components in these devices. One hundred or even a thousand, forcing the charging device to increase the number of storage elements to use the voltage converter, not only increases the complexity and uncertainty of the overall charging circuit, but also increases the overall cost.

Therefore, how to balance the voltage between the cells or the battery cells in the charging module, thereby avoiding the temperature of the battery module being too high and improving the life of the battery module is a problem to be solved.

In view of this, the object of the present invention is to provide a multi-stage battery module charging method, which is to divide the constant current charging into several stages, each stage has different current values and charging time, and when the charging reaches a predetermined voltage, Perform constant voltage charging. The method of adopting the staged constant current charging can solve the problem that the battery is overheated and the battery life is lowered by the conventional charging of the preset voltage in a short time.

Another object of the present invention is to provide a multi-segment battery module charging method, which is to divide the constant current charging into a first-stage charging, a second-stage charging, and a third-stage charging, and to charge in a second stage to a preset. When the voltage is applied, the current value is adjusted, and the battery that has not been charged to the preset voltage is charged in a third stage with a small current, and after the preset voltage is reached again, the constant voltage is charged. For the charging of the battery core that does not reach the preset voltage, the charger can be prevented from continuously charging the charged battery core, causing overcharge and over temperature problems, and ensuring that each battery core can be fully charged. The preset voltage maintains the voltage balance between the cells.

Another object of the present invention is to provide a multi-segment battery module charging device to implement the above-described multi-segment battery module charging method.

In order to achieve the above objects, a means of the present invention provides a multi-segment battery module charging method, the method comprising the following steps:

a. charging the battery module in a first stage with a first preset current;

b. determining, by a determining unit, whether the battery module reaches a predetermined voltage;

c. If it is determined that the preset voltage is reached, the battery module is subjected to the second stage charging with a second preset current;

d. If it is determined that the preset voltage is reached again, and a predetermined differential pressure is reached between the cells, or one of the cells exceeds the preset voltage, the third predetermined current is applied to the cell with a lower voltage. Carry out the third stage of charging;

e. If it is determined that the preset voltage is reached again, the battery module is fixedly charged with the preset voltage, and the second preset current is used as the initial charging current until the battery module is fully charged.

The second predetermined current is subtracted from the first preset current by a current difference, the third preset current is the second preset current minus a current difference, and the current of each phase is appropriately matched. The charging time, such step by step charging up to the preset voltage, can improve the conventional practice of charging the preset voltage once in a short time, so that the battery module of the present invention does not have an excessive temperature when it is charged. Battery life issues.

Wherein, the method for the third stage charging of the battery with lower voltage is to set a switching circuit corresponding to each battery core, and when it is determined that the battery core is charged to a preset voltage or a preset pressure difference is reached between the batteries; When the switch circuit is turned on, the current is passed, and the battery with a lower voltage is charged, so that each of the cells can be charged to a predetermined voltage, and no overcharge of the battery occurs.

Another means of the present invention is to provide a multi-segment battery module charging device, the device comprising:

a battery module comprising a plurality of cells connected in series;

a charger coupled to the battery module to form a charging circuit for supplying current to the battery module;

A battery management system is connected to the two poles of each of the cells for monitoring the voltage of each cell or the voltage difference between the cells, and adjusting the charging circuit accordingly.

The battery management system is provided with a switch circuit corresponding to each of the batteries, and the switch circuit includes a resistor and a switch component. The switching circuit is initially in a state that is not yet electrically connected to the charging circuit. When the battery management system detects that a predetermined differential pressure is between each of the cells or one of the cells exceeds a predetermined voltage, the switching element is turned on by controlling the switching element. Switching circuit and charging circuit. At this time, the current will not flow to the fully charged battery, but will flow to the switching circuit. First, a part of the current is consumed through the resistor, and the remaining small current (the third preset current) is again The battery with a lower voltage is charged.

The above method can achieve the purpose of "charging a cell with a lower voltage" in the present invention, and the present invention can save more energy by inductive energy storage and charging device with a plurality of switches to guide the current direction compared with the prior art. cost.

The embodiments of the present invention will be described in more detail below with reference to the drawings and the <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt;

Please refer to the first figure for the flow chart of the steps of the charging method of the multi-stage battery module of the present invention. The method includes the following steps: performing a first stage charging on the battery module with a first preset current (step S10); determining, by a determining unit, whether the battery module reaches a predetermined voltage, if the preset voltage has not been reached yet And continuing to charge with the first preset current until the preset voltage is reached (step S20); if it is determined that the preset voltage is reached, the second preset charging of the battery module by a second preset current (step S30) The determining unit determines whether the battery module reaches the preset voltage, and if the preset voltage has not been reached, continues to charge with the second preset current until the preset voltage is reached (step S40); When the preset voltage is reached again, and a predetermined differential pressure is reached between the cells, or one of the cells exceeds the preset voltage, the third-stage charging is performed with a third preset current for the lower-voltage battery. (Step S50); determining, by the determining unit, whether the battery with the lower voltage reaches the preset voltage, and if the battery core has not reached the preset voltage, continuing to charge with the third preset current until the battery core reaches the preset Set voltage (step S60) If it is determined that the preset voltage is reached again, the battery module is fixedly charged with the preset voltage, and the second preset current is used as the initial charging current until the battery module is full (steps) S70).

Please refer to the second figure for a schematic diagram of the charging state of the battery module of the present invention. The horizontal axis represents the time of current charging, and the vertical axis simultaneously shows the current magnitude and a preset voltage value. In a preferred embodiment of the present invention, a first preset current I ₁ is first provided to perform a first-stage constant current charging on the battery module for a time t=t ₀ to t ₁ , and then a judgment unit is disclosed. Determine whether the battery module reaches a preset voltage V ₁ . In the figure, when S ₁ is the first stage of charging, the voltage curve of the battery module changes, and the figure shows the voltage value of the battery module when the time reaches t ₁ . The preset voltage V ₁ is just reached; wherein the preset voltage V ₁ represents a maximum voltage that can be withstood when a cell is safely operated, for example 4.1V. Then, the second preset current I _{2 is used} to charge the battery module in the second stage of t ₁ ~ t ₂ , and the position of the battery module can be reduced due to the consideration of the first stage charging. Therefore, the current supplied in the second stage must be the value after the first predetermined current minus the current difference ΔI _a to maintain the safety of the battery module. Then, the determining unit determines whether the battery module reaches the preset voltage V ₁ . In the figure, when the S ₂ is the second stage charging, the voltage curve of the battery module changes, and the figure shows that when the time reaches t ₂ , the battery module The voltage value of the group just reaches the preset voltage V ₁ ; at the same time, the judging unit monitors whether a predetermined differential pressure is reached between the cells, or whether one of the cells exceeds the preset voltage V ₁ (ie, whether there is electricity) If the core is fully charged, but the other cells are not fully charged, if the preset differential pressure is reached or one of the cells exceeds the preset voltage, the third preset current I ₃ is changed to a lower voltage. The battery is subjected to a third stage constant current charging of t ₂ to t ₃ . Similarly, the current supplied in the third stage must be a value of the second predetermined current minus a current difference ΔI _B . Then, the determining unit determines whether the battery module reaches the preset voltage V ₁ . In the figure, when the S ₃ is the third stage charging, the voltage curve of the battery module changes, and the figure shows that when the time reaches t ₃ , the battery module The voltage value of the group just reaches the preset voltage V ₁ . Then to the determination unit determines whether the battery module reaches the predetermined voltage V ₁ is, if the reaches a predetermined voltage, the battery module I ₂ change for the predetermined time and the second predetermined voltage V ₁ is current t ₃ ~t ₄ constant voltage charging until the battery module is full, the figure shows the voltage curve of S ₄ for this stage, which is maintained at a certain voltage. As the battery module is almost fully charged, the required current amount gradually cut back.

Please refer to the fourth picture together with the second picture to better understand the temperature change of the battery module during each charging phase. The first stage charging is performed by the first preset current I ₁ during the period from t ₀ to t ₁ , and when the voltage reaches the preset voltage V ₁ , the corresponding temperature will rise to T ₁ , and the battery is made. The module has a crisis of overheating. Therefore, the present invention will perform a second charging of the battery module. The charging of the second stage is to use a second preset current I ₂ that is much lower than the first preset current I ₁ . The module is charged, the battery module is charged to the preset voltage V ₁ by a lower voltage, and the second phase charging time is t ₁ ~ t ₂ , which is longer than the first phase charging time. The temperature of the battery module is thus decreased from T ₁ to T ₂ ; then, the third-stage charging is performed, and the charging at this stage is to charge the battery cell that has not reached the preset voltage V ₁ by the third preset current I ₃ , wherein I _{3 is} smaller than I ₂ and I ₁ ; and the initial charging voltage reaches the preset voltage V _{1 at} this stage, and the elapsed time is t ₂ ~ t ₃ , which is less than the charging time of the second stage, and the temperature is lowered from T _{2 .} to T _3; a final stage of charge as compared to previous charging phase is different from a preset voltage V ₁ is feed Constant voltage charge, and a second current I ₂ as preset initial charging current over the charging time of this stage is t ₃ ~ t _4, is maintained at a temperature of about about T _3.

Please refer to the third figure for the circuit diagram of the multi-section battery module charging device of the present invention. The utility model comprises a battery module 1, a battery management system 2 and a charger 3. The battery module 1 can be a plurality of cells 11 and 12 connected in series as shown in the figure, or a plurality of cells connected in series with each other (not shown); the charger 3 is connected with the battery module 1 a charging circuit for supplying a current to the battery module 1; the battery management system 2 is connected to the two poles of each of the cells 11, 12 for monitoring the voltage of each of the cells 11, 12 and the cells 11; The voltage difference between 12, and according to the adjustment of the charging circuit, so that the voltage of each of the cells 11, 12 can be balanced. The battery management system 2 further includes a switch circuit 22 for adjusting a circuit for charging each of the cells. The switch circuit 22 is initially in a state that is not yet electrically connected to the charging circuit; wherein the switch circuit 22 has a control for charging a switching element 21 of the circuit, the switching element 21 is a Metal-Oxide-Semiconductor Field-Effect Transistor (MOSFET), respectively disposed at a position corresponding to each of the cell circuits, and the source 211 of the switching element 21 is transmitted through A resistor 23 is connected to the anode of each of the cells, a drain 212 is connected to the cathode of each of the cells, and a gate 213 is connected to the battery management system 2. A discharge control switch 24 and a charge control switch 25 are connected between the battery management system 2, the charger 3 and the battery module 1. The discharge control switch 24 is activated when the voltage of the battery is too low, the discharge current is too large, and the short circuit occurs. The charge control switch 25 is protected as the cell voltage is too high.

Please refer to the first to third figures at the same time to understand the charging method of the multi-section battery module of the present invention. The first preset current I _{1 is} supplied by the charger 3 to perform the first stage charging of the battery module 1 (step 10), and the determining unit (ie, the battery management system 2) determines whether the battery module 1 reaches the preset voltage V _{1 .} If the preset voltage V ₁ has not been reached, the charging is continued with the first preset current I ₁ until the preset voltage is reached (step S20). If it is determined that the preset voltage V _{1 is} reached, the charger 3 is changed to supply. The second preset current I ₂ performs second-stage charging on the battery module 1 (step S30). As can be seen from the second figure, the second predetermined current I _{2 of the} second-stage charging is smaller than the first preset current of the first-stage charging. I ₁ ; wherein, during the first stage charging and the second stage charging, the current flows in the I ₁ and I ₂ directions as indicated in the third figure. In the judgment unit (i.e., a battery management system 2) determines that the battery module 1 reaches the predetermined voltage V _1, if not yet reached the preset voltage, to continue the second predetermined charging current I _2, until the pre- voltage setting (step S40), if the determination unit (battery management system 2) determines the charging voltage reaches a predetermined V _1, the determination unit (battery management system 2) simultaneously detects whether or not each cell reaches a preset pressure between 11 and 12 Poor or whether one of the cells exceeds the preset voltage V ₁ (as in the third diagram, after the battery 11 has been charged for two stages, the voltage has reached the preset voltage, and the lower cell 12 is not fully charged). The battery management system 2 provides a signal to the gate 213 of the switching element 21 to turn on the source 211 and the drain 212, and the switching circuit 22 is connected to the charging circuit, and the current discharged from the charger 3 no longer flows to the battery. The core 11 flows to the switching circuit 22, and a part of the current is first consumed through the resistor 23, and the remaining minute current (the third predetermined current I ₃ ) flows to the underlying battery cell 12 (step S50), and then The determining unit (battery management system 2) determines whether the battery cell 12 reaches the preset voltage V _1, if the cell 12 has not reached the preset voltage, to continue the predetermined current I ₃ of the third charge, until the cell 12 reaches a predetermined voltage V ₁ (the S60 step), when the judging unit (battery management system 2) detecting every single cell 11 are preset voltage V ₁ is reached, the charger 3 will be changed to the predetermined voltage V ₁ is constant voltage charging until the battery pack 1 is fully charged (step S70).

The main feature of the present invention is that after the charger performs several stages of charging on the battery module, the battery management system activates the switching circuit, so that the charger charges the battery of the minimum voltage, so that the voltage between the batteries is balanced to avoid saturation. The battery is overcharged, causing excessive temperature to affect battery life. Another feature is that the battery module is charged in a fractional phase, and each phase is charged with a preset voltage by using different current values and different charging times. Compared with the prior art, the battery is charged to a preset voltage with a certain current. The way of the invention, or the way of switching the charger, the method of the invention can avoid the increase of the battery temperature during charging, and improve the charging efficiency and prolong the battery life. In addition, the multi-section battery module charging method provided by the invention can be applied to various mobile power management and energy storage systems.

The above is only a preferred embodiment for explaining the present invention, and is not intended to limit the invention in any way, so that any modifications or changes relating to the invention may be made in the spirit of the same invention. All should still be included in the scope of the intention of the present invention.

S10~S70. . . Steps for charging a multi-section battery module according to an embodiment of the present invention

I ₁ . . . First preset current

I ₂ . . . Second preset current

I ₃ . . . Third preset current

V ₁ . . . Preset voltage

S ₁ . . . The voltage curve of the battery module changes during the first stage of charging

S ₂ . . . The voltage curve of the battery module changes during the second phase of charging

S ₃ . . . The voltage curve of the battery module changes during the third phase of charging

S ₄ . . . The final stage of constant current charging, the voltage curve of the battery module changes

△I _a . . . Current difference

△I _b . . . Current difference

1. . . Battery module

11. . . Batteries

12. . . Batteries

2. . . Battery management system

twenty one. . . Switching element

211. . . Source

212. . . Bungee

213. . . Gate

twenty two. . . Switching circuit

twenty three. . . resistance

twenty four. . . Discharge control switch

25. . . Charging control switch

3. . . charger

I _B . . . Constant current

V _pc . . . Battery module voltage change

V _inc . . . Voltage

V _emax . . . Battery group maximum voltage

V _coff . . . Rated voltage

V _con . . . Lower voltage limit

V _emin . . . Battery group minimum voltage

The first figure is a flow chart of the steps of the charging method of the multi-stage battery module of the present invention.

The second figure is a schematic diagram of the charging state of the battery module of the present invention.

The third figure is a schematic circuit diagram of a multi-section battery module charging device of the present invention.

The fourth figure shows a schematic diagram of the temperature change of the battery module during each phase of charging.

The fifth figure is a schematic diagram of a conventional battery charging state.

The sixth figure is a schematic diagram of another conventional battery charging state.

The seventh figure is a schematic diagram of another conventional battery charging state.

S ₁ . . . The voltage curve of the battery module changes during the first stage of constant current charging

S ₂ . . . The voltage curve of the battery module changes during the second stage of constant current charging

S ₃ . . . The voltage curve of the battery module changes during the third stage of constant current charging

S ₄ . . . The final stage of constant voltage charging, the voltage curve of the battery module changes

I ₁ . . . First preset current

I ₂ . . . Second preset current

I ₃ . . . Third preset current

△I _a . . . Current difference

△I _b . . . Current difference

V ₁ . . . Preset voltage

t ₀ ~ t ₁ . . . First stage constant current charging time

t ₁ ~t ₂ . . . Second stage constant current charging time

t ₂ ~t ₃ . . . Third stage constant current charging time

t ₃ ~ t ₄ . . . Final stage constant voltage charging time

Claims (15)

A multi-section battery module charging method, the method comprising the steps of: a. charging a battery module in a first stage with a first preset current; b. determining, by a determining unit, whether the battery module reaches a preset Voltage; c. If it is determined that the preset voltage is reached, the second preset charging is performed on the battery module by a second preset current; d. if it is determined that the preset voltage is reached again, and each battery core reaches a pre-set When the voltage difference or one of the cells exceeds the preset voltage, the third stage charging is performed with a third preset current for the lower voltage battery; e. if it is determined that the preset voltage is reached again, The battery module is fixedly charged by the preset voltage, and the second preset current is used as the initial charging current until the battery module is fully charged. According to the charging method of the multi-stage battery module of claim 1, wherein the second preset current is the first preset current minus a current difference, and the third preset current is the second The preset current is subtracted from a current difference. The multi-segment battery module charging method according to claim 1, wherein the predetermined voltage is a voltage maximum value that can be withstood when each battery cell operates safely. The multi-section battery module charging method according to claim 1, wherein the determining unit is a battery management system. The multi-section battery module charging method according to claim 4, wherein the battery management system provides a switching circuit, and in step d, each of the batteries reaches a preset pressure difference or one of the batteries When the preset voltage is exceeded, the battery management system controls to turn on the switch circuit for the third preset current to pass, to perform the third stage charging on the lower voltage battery. The multi-segment battery module charging method according to claim 5, wherein the switching circuit comprises a resistor and a switching element, and the switching element is a field effect transistor (Metal-Oxide-Semiconductor Field-Effect Transistor) , MOSFET), the switching circuit is disposed at a position corresponding to each of the cell circuits. The multi-segment battery module charging method according to claim 6, wherein a source and a drain of the switching element are respectively connected to two poles of the corresponding core, and a gate and the battery management system are respectively connection. The multi-segment battery module charging method according to claim 1, wherein the battery cell is a battery cell group connected in series. The multi-segment battery module charging method according to claim 1, wherein the battery core is a plurality of serial battery groups connected in series with each other. A multi-segment battery module charging device includes: a battery module including a plurality of cells connected in series; a charger connected to the battery module to form a charging circuit to provide a current to the battery module; A battery management system is connected to the two poles of each of the cells for monitoring the voltage difference between the cells and the voltage difference between the cells, and adjusting the charging circuit accordingly. The multi-segment battery module charging device according to claim 10, wherein the battery management system is provided with a switching circuit corresponding to each of the batteries, and the switching circuit is initially in a state that has not been electrically connected to the charging circuit, when the battery When the management system detects that a preset differential pressure is reached between each of the cells or one of the cells exceeds a predetermined voltage, then the switch circuit is controlled to be connected to the charging circuit for current to pass, so that the charger is for a smaller voltage. The battery is charged. The multi-segment battery module charging device according to claim 11, wherein the switching circuit comprises a resistor and a switching element, and the switching element is a field effect transistor (Metal-Oxide-Semiconductor Field-Effect Transistor) , MOSFET), the switching circuit is disposed at a position corresponding to each of the cell circuits. The multi-section battery module charging device according to claim 12, wherein a source and a drain of the switching element are respectively connected to two poles of the corresponding core, and a gate and the battery are managed. System connection. The multi-segment battery module charging device according to claim 10, wherein the battery module comprises a plurality of series connected cells. The multi-segment battery module charging device according to claim 10, wherein the current is a first preset current, a second preset current, and a third preset current, and the first preset current is greater than the a second preset current, the second preset current being greater than the third preset current.