WO2020051888A1 - Voltage equalization circuit, series-connected battery pack, and electronic device - Google Patents

Abstract

A voltage equalization circuit (10), a series-connected battery pack (20), and an electronic device. The voltage equalization circuit (10) is applied to the series-connected battery pack (20), and the series-connected battery pack (20) comprises n batteries connected in series. The voltage equalization circuit (10) comprises: a voltage divider circuit (11). A first end (111) of the voltage divider circuit (11) is connected to the positive electrode of the series-connected battery pack (20), and a second end (112) of the voltage divider circuit is connected, via a resistor (12), to a positive electrode of an mth battery in the series-connected battery pack (20), where m is counted from the negative electrode of the series-connected battery pack. The negative electrode of the series-connected battery pack (20) is grounded. A voltage of the second end (112) of the voltage divider circuit (11) is m / n times a voltage of the first end (111) of the voltage divider circuit (11), wherein n is an integer greater than 1, and m is an integer greater than or equal to 1 and less than n. The voltage equalization circuit (10), the series-connected battery pack (20), and the electronic device have simple structures and low costs, thereby improving a utilization rate and extending a service life of the series-connected battery pack (20).

Description

Voltage balancing circuit, series battery pack and electronic equipment Technical field

The present application relates to the field of batteries, and in particular, to a voltage equalization circuit, a series battery pack, and an electronic device.

Background technique

Lithium batteries have the advantages of high nominal voltage, high specific energy, high charge and discharge efficiency, and long life. They are widely used in the field of battery energy storage for electric devices such as electric cars, notebook computers, and mobile phones. Lithium batteries with the same performance are used in series, and they also have the advantages of increasing the use voltage and reducing the charging current. Therefore, lithium batteries are usually used in series in the field of battery energy storage.

Lithium batteries in series batteries may have inconsistent performance as they are used more often. When charging a series battery pack, there may be situations where one battery is fully charged and the other is not yet fully charged. If you continue to charge the battery pack, it will cause the lithium battery that has been fully charged to release lithium, which will cause the battery to overheat or even burn out, posing a safety risk. However, if charging is abandoned, there is a problem that the capacity of the battery pack is wasted.

In order to solve the above problem, a common processing method is to use a controller to monitor the voltage of each battery. When it is found that the battery voltage is too high, by closing the switch of the parallel circuit of the battery, a resistor is connected in parallel to the battery, so that the battery flows into the battery. Part of the current is shunted to the resistor, which reduces the current flowing into the battery and slows down the charging speed of the battery. However, the way the controller monitors the voltage of each battery is costly.

Summary of the Invention

The present application provides a voltage equalization circuit, a series battery pack, and an electronic device, which are used to solve the problem that traditional series battery pack equalization requires a controller to monitor the voltage of each battery, and the cost is relatively high.

A first aspect of the present application provides a voltage equalization circuit, which is applied to a series battery pack, where the series battery pack includes n batteries in series; the voltage equalization circuit includes: a voltage dividing circuit; The first end of the voltage dividing circuit is connected to the positive electrode of the series battery pack, and the second end of the voltage dividing circuit is connected to the mth battery in the series battery pack from the negative electrode of the series battery pack through a resistor. The positive terminal is connected, and the negative terminal of the series battery pack is grounded; the voltage of the second terminal of the voltage dividing circuit is m / n times the voltage of the first terminal of the voltage dividing circuit, and n is an integer greater than 1. Let m be an integer greater than or equal to 1 and less than n.

The above voltage equalization circuit has a simple structure and low cost. At the same time, the voltage equalization circuit can also make the series battery pack work normally when at least one of the m + 1th battery to the nth battery has an open circuit or a sudden increase in resistance, which improves the series battery pack. Utilization and service life.

In a possible implementation manner, the voltage equalization circuit further includes: a control circuit and a first switch; a second end of the voltage dividing circuit is connected to the resistor through the first switch, and the control circuit is connected to the resistor The control terminal of the first switch is connected.

By setting the control circuit and the first switch, the control circuit controls the opening and closing of the first switch, so as to determine whether to balance the series battery pack. The equalization function of the voltage equalization circuit in this embodiment is controllable.

In a possible implementation manner, the control circuit is respectively connected to the positive electrode of the series battery pack and the positive electrode of the m-th battery; and the control circuit is configured to detect the When the voltage at the positive electrode is not equal to m / n times the voltage at the positive electrode of the series battery pack, the first switch is controlled to be closed.

In a possible implementation manner, the voltage equalization circuit further includes: a second switch; one end of the second switch is connected to the positive electrode of the m-th battery, and the other end of the second switch is grounded, The control circuit is respectively connected to a control terminal of the second switch and a control terminal of the voltage dividing circuit; the control circuit is in m batteries of the series battery pack from the negative electrode of the series battery pack. When the impedance of at least one battery is greater than or equal to a preset threshold, the first switch is controlled to be open, the second switch is closed, and the output voltage of the voltage dividing circuit is adjusted to be equal to the input voltage of the voltage dividing circuit. the same.

The voltage equalization circuit provided in this embodiment further includes a second switch. The second switch is connected in parallel with the first m batteries from the negative electrode of the series battery in the series battery pack, and can be closed when there is a battery disconnection in the first m batteries, so that The remaining nm cells in the series battery pack work normally, which further improves the utilization rate and service life of the series battery pack.

In a possible implementation manner, the voltage equalization circuit further includes: a second switch; one end of the second switch is connected to the positive electrode of the m-th battery, and the other end of the second switch is grounded. The control circuit is respectively connected to the control terminal of the second switch and the control terminal of the voltage dividing circuit; the control circuit is respectively connected to the positive electrode of each of the batteries in the series battery pack; the control circuit is detecting When the voltage of the kth battery from the negative electrode of the series battery to the series battery is less than the second preset voltage or the voltage change rate is greater than the preset change rate, if k is less than or equal to the m , The first switch is controlled to be open, and the second switch is closed; if k is greater than the m, the first switch is controlled to be closed, and the second switch is opened; wherein the value of k is Is an integer from 1 to n.

In a possible implementation manner, the n is equal to 2 and the m is equal to 1.

In a possible implementation manner, a first end of the voltage dividing circuit is connected to a positive electrode of an nth battery of the series battery pack, and a negative electrode of the first battery of the series battery pack is grounded.

In a possible implementation manner, the voltage dividing circuit includes p second terminals; the voltage of the i-th second terminal of the voltage dividing circuit is q times the voltage of the first terminal of the voltage dividing circuit, The i-th second terminal is connected to the positive electrode of the j-th battery in the series battery pack from the negative electrode of the series battery pack through a resistor corresponding to the i-th second terminal; p is A positive integer less than n, the value of i is an integer from 1 to p, the value of q is j / n, and j is an integer greater than or equal to 1, and less than n.

By connecting the p second ends of the voltage dividing circuit to the corresponding batteries of the series battery pack, the balancing effect on the series battery pack can be further improved.

A second aspect of the present application provides a series battery pack, including: n batteries connected in series, and a voltage equalization circuit in any one of the possible implementation manners of the first aspect, where n is an integer greater than 1.

A third aspect of the present application provides an electronic device including: a voltage equalization circuit, a power consumption circuit, and a series battery pack as in any possible implementation manner of the first aspect above, where the series battery pack includes n batteries connected in series N is an integer greater than 1; a second end of the voltage dividing circuit of the voltage equalization circuit is connected to the first end of the power consumption circuit, and the second end of the power consumption circuit is grounded.

Based on the implementations provided in the above aspects, this application can be further combined to provide more implementations.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic structural diagram of a series battery pack according to an embodiment of the present application; FIG.

2 is a schematic structural diagram of a voltage equalization circuit provided in Embodiment 1 of the present application;

FIG. 3 is a schematic schematic diagram 1 of a voltage equalization circuit provided in Embodiment 1 of the present application; FIG.

4 is a schematic diagram 2 of a principle of a voltage equalization circuit provided in Embodiment 1 of this application;

FIG. 5 is a third schematic diagram of a voltage equalization circuit provided in Embodiment 1 of this application; FIG.

FIG. 6 is a schematic diagram 4 of a principle of a voltage equalization circuit provided in Embodiment 1 of this application;

7 is a schematic structural diagram of a voltage equalization circuit provided in Embodiment 2 of the present application;

8 is a schematic structural diagram of a voltage equalization circuit provided in Embodiment 3 of the present application;

9 is a schematic structural diagram of a voltage equalization circuit provided in Embodiment 4 of the present application;

10 is a schematic structural diagram of a voltage equalization circuit provided in Embodiment 5 of the present application;

FIG. 11 is a schematic structural diagram of a voltage equalization circuit provided in Embodiment 6 of the present application.

Reference signs:

10—voltage equalization circuit;

11—Voltage divider circuit;

111—the first end of the voltage dividing circuit;

112—the second end of the voltage dividing circuit;

12—resistance;

13-control circuit;

14—first switch;

15—second switch;

20—series battery pack;

30—Power-consuming circuit.

detailed description

The technical solutions in the embodiments of the present application will be described below with reference to the drawings in the embodiments of the present application.

FIG. 1 is a schematic structural diagram of a series battery pack according to an embodiment of the present application. As shown in FIG. 1, the series battery pack includes: at least two batteries. The series battery pack shown in FIG. 1 includes n batteries, and the n batteries are connected in series.

For example, when n batteries are connected in series, the n batteries may be placed horizontally / vertically in sequence, and then the positive electrode of the adjacent next battery is connected to the negative electrode of the previous battery, and the positive electrode of the remaining battery is connected to the other battery. The negative electrode of the battery is the positive and negative electrodes of the entire series battery pack.

For example, as shown in FIG. 1, in order to facilitate the description of the n batteries in the series battery pack in the following embodiments of the present application, the present application makes an agreement on the numbers of the n batteries in the series battery pack. In the following embodiments of the present application, starting from the negative electrode of a series battery pack, n batteries are numbered sequentially from the first battery to the n battery. Therefore, the negative electrode of the first battery is the negative electrode of the entire series battery pack, and the positive electrode of the nth battery is the positive electrode of the entire series battery pack.

It can be understood that each battery in the series battery pack is a battery with consistent performance, for example, a battery with the same voltage and capacity. It can also be understood that the batteries in the series battery pack can also be placed in other forms, as long as the batteries in the series battery pack are connected in series. The number of the batteries in the series battery pack indicates that the battery is in a series circuit. Position, not the relative physical position of each battery when placed. Exemplarily, the battery in the series battery pack may be a lithium battery.

With the use of series battery packs, there may be inconsistencies in the performance of the batteries in the series battery packs. At this time, when the smaller capacity battery in the series battery pack is fully charged, the larger capacity battery is not fully charged. . If the battery pack is continuously charged, it will lead to lithium evolution of the fully-charged battery, causing the fully-charged battery to heat up or even burn out, posing a safety risk. However, if charging is stopped when a battery with a small capacity is fully charged, the capacity of the series battery pack will be seriously reduced, which not only wastes the capacity of the battery pack, but also increases the charging frequency of the user, which seriously affects the user's experience.

A common solution to the above-mentioned problem that the series battery pack cannot be balancedly charged is to use a controller to monitor each battery in the series battery pack. For a battery that is overcharged, that is, a battery with a high voltage, one battery can be connected in parallel. The resistor makes a portion of the charging current that originally flows through the battery shunt to the resistance, which reduces the charging current flowing into the battery, thereby slowing down the charging speed of the battery, and thus making the entire battery pack charge in a balanced manner. The battery is fully charged at the same time, avoiding waste of battery capacity and overcharging the battery. However, it is more expensive for the controller to monitor each battery and configure a parallel resistor for each battery.

The following embodiments of the present application provide at least a voltage equalization circuit, a series battery pack, and electronic equipment, which can solve the problem that the series battery pack cannot be balancedly charged, and has a simple structure and low cost.

On the one hand, the embodiments of the present application provide a voltage equalization circuit, which can be applied to the series battery pack shown in FIG. 1 to solve the problem that the series battery pack cannot be uniformly charged and discharged.

FIG. 2 is a schematic structural diagram of a voltage equalization circuit provided in Embodiment 1 of the present application. As shown in FIG. 2, the voltage equalization circuit 10 can be applied to a series battery pack 20 of a power-consuming device such as a mobile phone, a tablet, a wearable device, and an electric vehicle. The voltage equalization circuit 10 includes a voltage dividing circuit 11. The first terminal 111 of the voltage dividing circuit 11 is connected to the positive electrode of the series battery pack 20. The second terminal 112 of the voltage dividing circuit 11 is connected to the positive electrode of the m-th battery from the negative electrode of the series battery pack 20 in the series battery pack 20 through the resistor 12. The negative electrode of the series battery pack 20 is grounded.

Among them, the voltage of the second terminal 112 of the voltage dividing circuit 11 is m / n times the voltage of the first terminal 111 of the voltage dividing circuit 11, n is an integer greater than 1, m is an integer greater than or equal to 1, and less than n .

Exemplarily, as shown in FIG. 2, this embodiment uses the power consumption device including the voltage equalization circuit 10, the series battery pack 20, and the power consumption circuit 30 as an example for description. The series battery pack 20 is connected to the power consumption circuit 30 via the voltage equalization circuit 10. Taking a mobile phone as an example, the series battery pack 20 may be a battery of the mobile phone, and the power consumption circuit 30 may be a motherboard chip, a screen, etc. of the mobile phone. Optionally, when m is 1, n is 2, the voltage dividing circuit in the voltage equalization circuit 10 can be selected from the original 1/2 voltage dividing circuit in the mobile phone. When the user connects the mobile phone with the power supply, the power supply charges the series battery pack 20, and when the user disconnects the mobile phone from the power supply, the series battery pack 20 supplies power to the power consumption circuit 30.

Exemplarily, the power consumption circuit 30 may also be directly connected to the series battery pack 20 without passing through the voltage equalization circuit 10; or, it may be connected to the series battery pack through circuits other than the voltage equalization circuit 10 provided in this embodiment, such as switches. 20 connections.

It is worth noting that the series battery pack 20 can also be charged separately. At this time, the series battery pack 20 is connected to the voltage equalization circuit 10, and the positive electrode of the series battery pack is connected to the power supply. When the series battery pack 20 stops charging and discharges, The positive electrode of the series battery pack is connected to the power consumption circuit 30.

In this embodiment, an example is described by adding a voltage equalization circuit 10 between the series battery pack 20 and the power consumption circuit 30 as an example.

Specifically, as shown in FIG. 2, the first end 111 of the voltage dividing circuit 11 in the voltage equalization circuit 10 is connected to the positive electrode of the series battery pack 20. When a user supplies power to the series battery pack 20, the first The terminal 111 and the positive electrode of the series battery pack 20 both receive the voltage provided by the power supply. When the series battery pack 20 supplies power to the power consumption circuit 30, the first terminal 111 of the voltage dividing circuit 11 receives the voltage provided by the series battery pack 20. The first terminal 111 of the voltage dividing circuit 11 is an input terminal, and the second terminal 112 is an output terminal. The input voltage V _{in of the} input terminal is the same as the voltage provided by the power supply and the voltage of the positive electrode of the series battery pack 20.

Specifically, the second end 112 of the voltage dividing circuit 11 is connected to the first end of the resistor 12, and the connection point is denoted as A. The second end of the resistor 12 is connected to the positive electrode of the m-th battery in the series battery pack 20. The connection point is denoted as B.

Among them, when there is a voltage difference between the two ends of the resistor 12, that is, points A and B, a current is generated in the resistor 12. Specifically, when the voltage at the point A is higher than the voltage at the point B, a current flows from the first terminal of the resistor 12 to the second terminal of the resistor 12. When the voltage at point A is lower than the voltage at point B, a current flows from the second terminal of the resistor 12 to the first terminal of the resistor 12.

Optionally, the resistor 12 may be a resistor, or may be a resistor circuit formed by multiple resistors connected in series or in parallel, which is not limited in this application.

Exemplarily, the voltage received by the first terminal 111 of the voltage dividing circuit 11 is denoted by V _in and the current is denoted by I _in , and the voltage output by the second terminal 112 of the voltage division circuit 11 is denoted by V _out and the current is denoted by I _out , Where V _{out is} lower than V _in , I _{out is} higher than I _in , and the power of the first end 111 of the voltage dividing circuit 11 is the same as the power of the second end 112, that is, V _in * I _in = V _out * I _out .

Exemplarily, V _out may be 1/2 times V _in or 1/3 times V _in and the like. In this embodiment, the voltage of the second terminal 112 of the voltage dividing circuit 11 is m / n times the voltage of the first terminal 111 of the voltage dividing circuit 11, that is, V _out = V _in * m / n, where n is a series connection. The number of batteries in a battery pack, n is an integer greater than 1. m is an integer greater than or equal to 1 and less than n. That is, V _out ranges from V _in * 1 / n to V _in * (n-1) / n.

In this embodiment, referring to the above connection method, the resistor 12 constitutes an equalization branch for balancing the charge and discharge of the first m batteries and the last nm batteries in the series battery pack 20 from the negative electrodes of the series battery pack. The principle analysis is as follows:

When charging the series battery pack 20:

The power supply source supplies power to the series battery pack 20. The voltage of the positive terminal of the series battery pack 20 and the first terminal of the voltage dividing circuit 11 is V _in , and the voltage of the second terminal of the voltage dividing circuit 11 is V _out , and V _out = V _in * m / n. The voltage of the positive electrode of the m-th battery in the series battery pack 20, that is, point B, is V _B. At this time, the power supply source supplies the charging current I ₁ to the series battery pack 20.

When the performance of each battery in the series battery pack 20 is the same and the charging is balanced, since the negative electrode from the point B to the series battery pack 20 includes m batteries, and the series battery pack 20 includes a total of n batteries, therefore, V _B = V _in * m / n = V _out . Therefore, the voltage across the resistor 12 is the same, and no current flows through the resistor 12. The power supply can continuously charge the cells of the series battery pack 20 in a balanced manner.

When the performance of each battery in the series battery pack 20 is inconsistent, for example, the first m batteries of the series battery pack 20, that is, from the first battery to the m battery from the negative electrode of the series battery pack 20, the charging speed is faster than the series battery In the remaining nm batteries of the group 20, at this time, the voltage V B at the point _{B is} greater than V _in * m / n = V _out , that is, the voltage at the point B of the resistor 12 is greater than the voltage at the point A.

FIG. 3 is a schematic diagram 1 of the principle of the voltage equalization circuit provided in Embodiment 1 of the application. As shown in FIG. 3, a current I ₃ from point B to point A will be generated in the resistor 12. The current Kirchhoff's current law, the remaining battery nm flowing through the series battery group 20 is I ₁ is equal to the current flowing through the resistor 12 and the current I ₃ m before flowing through the battery 20 and the series battery group ₂ of I , I ₁ = I ₂ + I _3. At this time, I ₂ <I ₁ . Accordingly, there is a balanced branch, such that flow through the series battery remaining of the battery 20 nm of the current I ₁ m before the current flowing through the battery 20, the series battery pack is greater than I _2, i.e., a portion of the charging current is diverted to the resistor 12, thereby slowing down the charging rate of the first m batteries that the charging power source charges to the series battery pack 20 faster. Exemplarily, after the current I ₃ flowing through the resistor 12 flows into the voltage divider circuit 11, the remaining nm cells provided to the series battery pack 20 through the first end of the voltage divider circuit 11 increase the balance of the series battery pack 20 The charging current I ₁ in the nm cells increases the charging speed of the remaining nm cells in the slow-charging series battery pack 20.

When the performance of each battery in the tandem battery pack 20 is inconsistent, for example, the first m batteries of the tandem battery pack 20 from the negative electrode of the tandem battery pack 20 have a slower charging speed than the remaining nm batteries of the tandem battery pack 20, at this time, The voltage V B at the point _{B is} smaller than V _in * m / n = V _out , and the voltage at the point B of the resistor 12 is smaller than the voltage at the point A.

FIG. 4 is a schematic diagram 2 of the principle of the voltage equalization circuit provided in Embodiment 1 of the present application. As shown in FIG. 4, a current I ₃ ′ from a point A to a point B will be generated in the resistor 12. According to Kirchhoff's current law, the sum of the current I ₁ flowing through the remaining nm cells of the series battery pack 20 and the current I ₃ ′ flowing through the resistor 12 is equal to the current I flowing through the first m cells of the series battery pack 20 ₂ ′, I ₁ + I ₃ ′ = I ₂ ′, at this time, I ₂ ′> I ₁ . At this time, the existence of the equalization branch makes the current I ₁ flowing through the remaining nm cells of the series battery pack 20 smaller than the current I ₂ ′ flowing through the first m batteries of the series battery pack 20, that is, a part of the charging current I ₃ is extra. ′ Charging the first m batteries of the series battery pack 20 with a slower charging speed increases the charging rate of the first m batteries of the series battery pack 20. At this time, a part of the current supplied from the charging current I ₁ supplied to the series battery pack 2 flows into the first end of the voltage dividing circuit 11, thereby slowing down the remaining nm cells of the series battery pack 20 that is charged faster. Charging speed.

When the series battery pack 20 is discharged:

The series battery pack 20 supplies power to the power consumption circuit 30. The voltage of the positive terminal of the series battery pack 20 and the first terminal of the voltage dividing circuit 11 is still recorded as V _in , and the voltage of the second terminal of the voltage dividing circuit 11 is also recorded as V _out . V _out = V _in * m / n. The voltage of the positive electrode of the m-th battery in the series battery pack 20, that is, point B, is V _B.

When the performance of each battery in the series battery pack 20 is the same and the discharge is balanced, since the negative electrode from the point B to the series battery pack 20 includes m batteries, and the series battery pack 20 includes a total of n batteries, therefore, V _B = V _in * m / n = V _out . Therefore, the voltage across the resistor 12 is the same, and no current flows through the resistor 12. The series battery pack 20 can continue to be discharged uniformly.

When the performance of each battery in the tandem battery pack 20 is inconsistent, for example, the first m batteries of the tandem battery pack 20, that is, the first to mth batteries, discharge faster than the remaining nm batteries of the tandem battery pack 20, At this time, the voltage V B at the point _{B is} smaller than V _in * m / n = V _out , and the voltage at the point B of the resistor 12 is smaller than the voltage at the point A.

FIG. 5 is a third schematic diagram of the voltage equalization circuit provided in Embodiment 1 of the present application. As shown in FIG. 5, a current I ₆ from point A to point B will be generated in the resistor 12. According to Kirchhoff's current law, the discharge current I ₄ of the remaining nm cells of the series battery pack 20 is equal to the sum of the current I ₆ flowing through the resistor 12 and the discharge current I ₅ of the first m batteries of the series battery pack 20, I ₄ = I ₅ + I _6. At this time, I ₅ <I ₄ . Therefore, the existence of the balanced branch makes the discharge current I ₄ of the remaining nm cells of the series battery pack 20 greater than the discharge current I ₅ of the first m cells of the series battery pack 20, thereby increasing the slower discharge of the series battery pack 20 The discharge rate of the remaining nm batteries.

When the performance of each battery in the tandem battery pack 20 is inconsistent, for example, the first m batteries of the tandem battery pack 20 have a slower discharge rate than the remaining nm batteries of the tandem battery pack 20, at this time, the voltage at point B V _{B is} greater than V _in * m / n = V _out , the voltage at the point B of the resistor 12 is greater than the voltage at the point A.

FIG. 6 is a fourth schematic diagram of the principle of the voltage equalization circuit provided in Embodiment 1 of the present application. As shown in FIG. 6, a current I ₆ ′ from the point B to the point A will be generated in the resistor 12. According to Kirchhoff's current law, the sum of the discharge current I ₄ of the remaining nm cells of the series battery pack 20 and the current I ₆ ′ flowing through the resistor 12 is equal to the discharge current I ₅ ′ of the first m cells of the series battery pack 20 , I ₄ + I ₆ ′ = I ₅ ′. At this time, I ₅ ′> I ₄ . At this time, the existence of the equilibrium branch makes the discharge current I ₄ of the remaining nm cells of the series battery pack 20 smaller than the discharge current I ₅ ′ of the first m batteries of the series battery pack 20, that is, a part of the discharge current I ₅ ′ flows. The resistance 12 is reduced, thereby reducing the discharge rate of the remaining nm cells of the series battery pack 20.

Exemplarily, referring to the above-mentioned principle analysis of FIG. 3 to FIG. 6, it can be known that when the voltage difference across the resistor 12 is constant, the larger the resistance of the resistor 12 is, the smaller the current flowing through the resistor 12 is. At this time, the equalization effect of the equalization branch where the resistor 12 is located is slower. The resistance value of the resistor 12 can be determined according to the equilibrium rate requirement of the series battery pack 20.

When the charged series battery pack 20 has not yet started to discharge, if the voltage at point B in the series battery pack 20 is less than m / n times the overall voltage of the series battery pack 20, at this time, the voltage at the point A of the resistor 12 is greater than the point B The voltage I ₆ is generated in the resistor 12 as shown in FIG. 5. The m + 1th to nth batteries in the series battery pack 20 provide a charging current to the voltage dividing circuit 11. After the voltage dividing circuit 11 increases the charging current, It is adjusted to I ₆ to charge the first m batteries of the series battery pack 20. If the voltage at point B in the series battery pack 20 is greater than m / n times the overall voltage of the series battery pack 20, at this time, the voltage at the point A of the resistor 12 is smaller than the voltage at the point B, and the current I ₆ in the resistor 12 is generated as shown in FIG. ′, After receiving the current I ₆ ′ at the second terminal of the voltage dividing circuit 11, the m + 1 to n-th batteries of the series battery pack 20 are charged through the first terminal. As a result, the voltages of the cells in the series battery pack 20 are balanced.

Exemplarily, referring to the above-mentioned principle analysis of FIGS. 3 to 6, it can be known that in this embodiment, a voltage equalization circuit 10 is provided between the power consumption circuit 30 and the series battery pack 20, and is generated by the voltage division circuit 11 in the voltage equalization circuit 10. m / n times the input voltage. At the same time, considering that the positive electrode voltage of the m-th battery in the series battery pack 20 containing n batteries should be equal to m / n times the input voltage, the voltage A resistor 12 is used to connect the second end of the voltage dividing circuit 11 and the positive electrode of the m-th battery in the series battery pack 20 to obtain an equalization branch. The existence of the balanced branch makes the resistor 12 in the resistor 12 to be unbalanced when the batteries in the series battery pack 20 are unbalanced. A current is generated, and the direction of the current varies with the charge and discharge of the series battery pack and the magnitude of the voltage of the positive electrode of the m-th battery in the series battery pack 20, thereby achieving the balance of the charge and discharge of the batteries in the series battery pack.

In this embodiment, when at least one of the m + 1th battery to the nth battery in the series battery pack 20 has a fault such as an open circuit or a sudden increase in resistance, the first to mth batteries in the series battery pack 20 Batteries can still work normally.

Specifically, when the failed series battery pack 20 is charged, the power supply source can charge the first m batteries of the series battery pack 20 through the voltage dividing circuit 11 and the resistor 12. When the failed series battery pack 20 is discharged, the first m batteries of the series battery pack 20 can supply power to the power consumption circuit 30 through the resistor 12. Therefore, the voltage equalization circuit provided in this embodiment can also enable the series battery pack to work normally under a partial fault condition, and improve the utilization rate of the series battery pack.

The embodiment of the present application provides a voltage equalization circuit, which can be applied to a series battery pack including n batteries connected in series. The voltage equalization circuit includes: a voltage dividing circuit; the first end of the voltage dividing circuit is connected to the positive electrode of the series battery pack, and the second end of the voltage dividing circuit is connected to the mth battery in the series battery pack from the negative electrode of the series battery pack through a resistor. The negative terminal of the series battery pack is grounded; the voltage at the second terminal of the voltage dividing circuit is m / n times the voltage at the first terminal of the voltage dividing circuit. In this embodiment, by adding a voltage equalization circuit between the power consumption circuit of the series battery pack and the series battery pack, an input voltage of m / n times is generated by the voltage dividing circuit in the voltage equalization circuit. The positive electrode voltage of the m-th battery in the series battery pack should also be m / n times the input voltage when the battery is uniformly charged and discharged. Therefore, a resistor is used to connect the second end of the voltage divider circuit to the The positive pole of the m-th battery, an equalization branch is obtained. The existence of a balanced branch makes it possible to generate a current in the resistor when the voltage of the positive electrode of the m-th battery in the series battery pack is unbalanced, and the voltage of the positive electrode of the m-th battery in the series battery pack is greater than or less than the voltage of the second terminal of the voltage dividing circuit, and The direction of the current changes with the charge and discharge of the series battery pack and the voltage of the positive electrode of the m-th battery in the series battery pack, which realizes the automatic equalization of the charge and discharge of the batteries in the series battery pack. The provided voltage equalization circuit has a simple structure and low cost. At the same time, the voltage equalization circuit can also make the series battery pack work normally when at least one of the m + 1th battery to the nth battery has an open circuit or a sudden increase in resistance, which improves the series battery pack. Utilization and service life.

Exemplarily, on the basis of the embodiment shown in FIG. 2, an embodiment of the present application further provides a voltage equalization circuit. FIG. 7 is a schematic structural diagram of a voltage equalization circuit provided in Embodiment 2 of the present application. The voltage equalization circuit provided in this embodiment further includes a control circuit and a first switch, which are used to control whether to balance the series battery pack. As shown in FIG. 7, the voltage equalization circuit 10 further includes: a control circuit 13 and a first switch 14;

The second terminal of the voltage dividing circuit 11 is connected to the resistor 12 through the first switch 14, and the control circuit 13 is connected to the control terminal of the first switch 14.

For example, a first switch 14 is provided on the equalization branch where the resistor 12 is located. When the first switch 14 is closed, the voltage equalization circuit 10 can work normally to balance the charge and discharge of the batteries in the series battery pack 20; When a switch 14 is open, the voltage equalization circuit 10 stops equalizing the charge and discharge of the batteries in the series battery pack 20.

Exemplarily, the control circuit 13 is connected to the control terminal of the first switch 14 and is used to control whether the first switch 14 is closed or open. The user can control the voltage balance circuit 10 to control the battery in the series battery pack 20 through the control circuit 13. Charge and discharge.

Optionally, the control circuit 13 may also receive the detection result of the detection circuit in the power consuming equipment where the series battery pack 20 is located, and control the first switch 14 to be closed or open according to the detection result. Exemplarily, the detection circuit may be a detection circuit that detects a voltage / current / resistance value in the series battery pack 20.

Optionally, the detection circuit may also be a service life detection circuit for a series battery pack. When it is detected that the service life of the series battery pack is less than the first preset age, it can be considered that the series battery pack has just started to use, and the performance is good, and no Charge and discharge are balanced. At this time, the control circuit 13 controls the first switch 14 to open. When it is detected that the service life of the series battery pack exceeds the second preset age, it can be considered that the series battery pack is old and the performance is too poor. At this time, the control circuit 13 also controls the first switch 14 to open, and no longer affects the series battery pack. Charge and discharge are balanced. Among them, the second preset period is greater than the first preset period.

Optionally, the control circuit 13 is further configured to close the first circuit when it is detected that at least one of the m + 1th battery to the nth battery in the series battery pack 20 has an open circuit or a sudden increase in resistance. Switch 14. Exemplarily, when the power consumption circuit 30 is connected to the second end of the voltage dividing circuit 11, since the first m batteries in the series battery pack at this time directly supply power to the power consumption circuit 30 through the resistor 12, there may be a series battery pack 20 If the voltage provided exceeds the maximum voltage that the power consumption circuit 30 can accept, the control circuit 13 is further configured to control the first switch when the voltage provided by the series battery pack 20 exceeds the maximum voltage that the power consumption circuit 30 can accept. 14 open.

An embodiment of the present application provides a voltage equalization circuit, further including a control circuit and a first switch. The first switch is connected in series with a resistor. The control circuit is used to control the first switch to open and close, thereby determining whether to balance the series battery pack. The equalization function of the voltage equalization circuit in this embodiment is controllable.

Exemplarily, on the basis of the embodiment shown in FIG. 7, an embodiment of the present application further provides a voltage equalization circuit. FIG. 8 is a schematic structural diagram of a voltage equalization circuit provided in Embodiment 3 of the present application. This embodiment provides a specific structure of the detection circuit, and an implementation manner of controlling whether the first switch is closed according to a detection result of the detection circuit. As shown in FIG. 8, the control circuit 13 is respectively connected to the positive electrode of the series battery pack 20 and the positive electrode of the m-th battery;

A control circuit 13 is used to control the first switch 14 to be closed when it is detected that the voltage at the positive electrode of the m-th battery is not equal to m / n times the voltage at the positive electrode of the series battery pack 20.

Exemplarily, the two input pins of the control circuit 13 are also connected to the positive electrode of the series battery pack 20 and the positive electrode of the m-th battery, respectively, for detecting the voltage of the positive electrode of the series battery pack 20 and the positive electrode of the m-th battery respectively. . When the control circuit 13 detects that the voltage at the positive electrode of the m-th battery is not equal to m / n times the voltage at the positive electrode of the series battery pack 20 according to the input voltage of the input pin, it controls the first switch 14 to close. After the first switch 14 is closed, the voltage equalization circuit 10 can realize automatic equalization according to the voltage of the second terminal of the voltage dividing circuit 11 and the voltage at the positive electrode of the m-th battery of the series battery pack 20.

Exemplarily, on the basis of any of the foregoing embodiments, an embodiment of the present application further provides a voltage equalization circuit. FIG. 9 is a schematic structural diagram of a voltage equalization circuit provided in Embodiment 4 of the present application. In this embodiment, the voltage equalization circuit further includes a second switch, which is used to solve the problem that the series battery pack cannot work when the first m batteries of the series battery pack are disconnected. As shown in FIG. 9, the voltage equalization circuit 10 further includes: a second switch 15;

One end of the second switch 15 is connected to the positive electrode of the m-th battery, and the other end of the second switch 15 is grounded; the control circuit 13 is connected to the control terminal of the second switch 15 and the control terminal of the voltage dividing circuit 11 respectively;

The control circuit 13 controls the first switch 14 to be open, and the second switch 15 to be closed when the impedance of at least one of the first m batteries of the series battery pack 20 from the negative electrode of the series battery pack 20 is greater than or equal to a preset threshold, and When the series battery pack 20 supplies power to the power consumption circuit 30 through the voltage divider circuit 11 and the positive voltage of the series battery pack 20 is less than the first preset voltage, the output voltage of the voltage divider circuit 11 is controlled to be adjusted to the input of the voltage divider circuit 11 The voltage is the same.

Exemplarily, the voltage equalization circuit shown in FIG. 9 is added with the second switch 15 on the basis of the embodiment shown in FIG. 7. As shown in FIG. 9, when at least one of the first m batteries of the series battery pack 20 has a fault such as an open circuit or a sudden increase in resistance, the series battery pack 20 cannot form a charge and discharge circuit and cannot work normally.

In order to avoid this problem, a second switch 15 is added in this embodiment, and the second switch 15 is arranged in parallel with the first m series batteries of the series battery pack 20. Among the current m series batteries, the battery impedance is greater than or equal to a preset threshold. At this time, the control circuit 13 controls the first switch 14 to be open, and the second switch 15 to be closed to short-circuit the first m series batteries. At this time, the negative electrode of the m + 1th battery of the series battery pack 20 is grounded, When the remaining nm batteries are charged and discharged, they can form a charge and discharge circuit and can work normally. Specifically, during charging, the power supply source charges the remaining n-m batteries of the series battery pack 20, and when discharging, the remaining n-m batteries of the series battery pack 20 supply power to the power consumption circuit 30 through the voltage dividing circuit 11.

For example, the control circuit 13 can determine whether the impedance of each battery is less than a preset threshold by monitoring the current flowing through each battery and the voltage across the battery. Optionally, the control circuit 13 may also receive the battery resistance detection results of other monitoring circuits in the power consuming equipment where the series battery pack 20 is located. For example, a temperature sensor may be present in the power consuming device, which is used to detect the temperature of each battery in the series battery pack 20. Since the resistance value of the battery decreases as the temperature increases, the temperature detected by the temperature sensor may indicate the resistance of the battery. Value, the control circuit 13 can obtain the detection result of the temperature of each battery by the temperature sensor, thereby obtaining the resistance value of each battery, and then determining whether the resistance value of each battery is greater than or equal to a preset threshold.

It is worth noting that when the first switch 14 is open and the second switch 15 is closed, the voltage provided by the series battery pack 20 to the power consumption circuit 30 through the voltage dividing circuit 11 decreases. When the voltage of the positive electrode of the series battery pack 20 is less than the first When the voltage is preset, the control circuit 13 also controls the output voltage of the voltage divider circuit 11 to be adjusted to be the same as the input voltage of the voltage divider circuit 11, that is, the voltage divider circuit 11 works in a through mode to avoid supplying an excessively low voltage to the power consumption circuit . Exemplarily, when the voltage of the positive electrode of the series battery pack 20 is not less than the first preset voltage, the voltage dividing circuit 11 still works in the voltage dividing mode.

It is worth noting that when the battery impedance of the first m series batteries is greater than or equal to a preset threshold, if the series battery pack 20 passes other voltage dividing circuits, but does not pass through the voltage dividing circuit 11 and the power consumption as shown in FIG. 9 When the electric circuit 30 is connected, the voltage dividing circuit 11 in FIG. 9 is not operated. The operating mode of the voltage divider circuit connecting the series battery pack 20 and the power consumption circuit 30 may still be a voltage divider mode, a through mode, or a voltage at the positive electrode of the series battery pack 20 not less than the first preset voltage. When the voltage of the positive electrode of the series battery pack 20 is less than the first preset voltage, it works in the through mode. Exemplarily, the first preset voltage may be a maximum voltage that the power-consuming circuit can accept.

In the embodiment of the present invention, the through mode, that is, the input voltage of the voltage dividing circuit 11 is the same as the output voltage, and the voltage dividing circuit is equivalent to a wire with almost zero impedance.

It can be understood that when the open-cell battery appears in the first m batteries and the rear nm batteries of the series battery pack 20, the control circuit 13 controls both the first switch 14 and the second switch 15 to be open. At this time, the series battery pack 20 is open. Charging and discharging can no longer be performed.

The voltage equalization circuit provided in this embodiment further includes a second switch. The second switch is connected in parallel with the first m batteries from the negative electrode of the series battery in the series battery pack, and can be closed when there is a battery disconnection in the first m batteries, so that The remaining nm cells in the series battery pack work normally, which further improves the utilization rate and service life of the series battery pack.

Exemplarily, on the basis of any of the foregoing embodiments, an embodiment of the present application further provides a voltage equalization circuit. Unlike the embodiment shown in FIG. 9, the control circuit 13 in this embodiment is further connected to a series battery pack, respectively. The positive connection of each battery in 20 is used to control the first switch and the second switch according to the voltage change of each battery.

In this embodiment, when the control circuit detects that the voltage of the k-th battery from the negative electrode of the series battery pack in the series battery pack is less than the second preset voltage or the voltage change rate is greater than the preset change rate, if k is less than or equal to m, the first switch is controlled to open, and the second switch is closed; if k is greater than m, the first switch is controlled to be closed, and the second switch is opened;

Wherein, the value of k is an integer from 1 to n.

Exemplarily, when the battery is broken, and the resistance value suddenly increases, the voltage across the battery will suddenly decrease. In this embodiment, the control circuit 13 is connected to the positive electrode of each battery in the series battery pack 20, and can be further The voltage across the battery changes to detect a battery failure in time. Specifically, the control circuit 13 may determine the battery failure according to the voltage magnitude or the rate of change of the voltage of the battery.

Specifically, when the k-th battery in the series battery pack 20 fails, when the k-th battery belongs to the first m batteries, the control circuit 13 closes the second switch and controls the first switch to open. When the k-th battery belongs to the last n-m batteries, the control circuit 13 closes the first switch and controls the second switch to open. In this embodiment, in the closed or open state of the first switch and the second switch, the control of the voltage divider circuit 11 by the control circuit 13 is the same as that in the embodiment shown in FIG. 9, which will not be described again in this application.

The second switch provided in this embodiment may be connected in parallel with the first m batteries in the series battery pack from the negative poles of the series battery pack. This embodiment determines whether there is a faulty battery according to the battery voltage and / or voltage change rate, and according to The number of the faulty battery in the series battery pack determines the opening and closing of the first switch and the second switch, so that when there is a faulty battery in the series battery pack, it can still work normally, which improves the utilization rate and service life of the series battery pack. .

A second switch can also be provided for each battery in the series battery pack, that is, a second switch is connected in parallel for each battery. The control circuit is connected to the control end of each second switch. Each second switch is open by default. When an open circuit fault is detected in a certain battery, the second switch corresponding to the battery is controlled to be closed.

At this time, the control circuit 13 also controls the first switch to be opened. The control of the voltage dividing circuit 11 by the control circuit 13 is the same as the control method in the embodiment shown in FIG. 9, which will not be described again in this application.

In the embodiments shown in FIGS. 2 to 9 of the present application, the power consumption circuit 30 is connected to the series battery pack 20 through a voltage dividing circuit of a voltage equalization circuit.

Optionally, another voltage dividing circuit may be provided on the power consuming equipment. The power consuming circuit 30 is connected to the series battery pack 20 through the voltage dividing circuit, and the voltage divider circuit adjusts the voltage and current provided by the series battery pack 20 The specific ratio of the output voltage to the input voltage and the ratio of the output current to the input current can be set according to the demand of the power consumption circuit 30. At this time, referring to FIG. 9, when there is a battery disconnection in the series battery pack 20, if the disconnected battery is any of the first m batteries, the second switch is closed and the first switch is controlled to open the circuit so that the series battery pack is open. 20 can still supply power to the power consumption circuit 30; if the disconnected battery is any of the last nm batteries, control the second switch to open and close the first switch so that the series battery pack 20 can still pass the voltage dividing circuit first 11. Power is supplied to the power consumption circuit 30 through the new voltage divider circuit. At this time, the voltage divider circuit 11 in the voltage equalization circuit and the voltage divider circuit added for the power consumption circuit can both work in the through mode or the voltage divider mode. It is also possible for one to work in the through mode and the other to work in the divided voltage mode. Optionally, when a second switch is connected in parallel for each battery, the second switch connected in parallel with the disconnected battery may be closed, so that the series battery pack 20 can still supply power to the power consumption circuit 30.

Exemplarily, on the basis of any of the foregoing embodiments, FIG. 10 is a schematic structural diagram of a voltage equalization circuit provided in Embodiment 5 of the present application. In this embodiment, the voltage equalization circuit includes multiple equalization branches, which further improves the equalization effect on the series battery pack. As shown in FIG. 10, the voltage dividing circuit includes p second terminals;

The voltage of the i-th second terminal of the voltage dividing circuit is q times the voltage of the first terminal of the voltage-dividing circuit. The i-th second terminal is connected in series with the slave in the series battery pack through a resistor corresponding to the i-th second terminal. The negative electrode of the battery pack is connected to the positive electrode of the jth battery;

Among them, p is a positive integer less than n, i is an integer from 1 to p, q is a value of j / n, and j is an integer greater than or equal to 1, and less than n.

Exemplarily, in order to further improve the equalization effect of the voltage equalization circuit on the series battery pack, a plurality of equalization branches may be provided between the voltage dividing circuit and the series battery pack. As shown in Figure 10. In FIG. 10, n is equal to 4 and p is equal to 3 as an example, the voltage equalization circuit provided in this embodiment is exemplarily described.

In this embodiment, the voltage dividing circuit includes three second terminals. Of course, the voltage dividing circuit may further include only one second terminal, or only include two second terminals as shown in FIG. 2. In this embodiment, three second ends may be numbered. As shown in FIG. 10, the voltage dividing circuit includes a first second end, a second second end, and a third second end. Optionally, each second end can be numbered in any order.

Exemplarily, each second terminal provides a different divided voltage with respect to the input voltage V _in . Specifically, the divided voltage that the second terminal can provide can be determined according to the number of batteries in the series battery pack. When a series battery pack includes n batteries, the voltage divided by any second end of the voltage dividing circuit can be q times V _in . The value of q is j / n, and the range of j is [1. , N-1], that is, j / n can be from 1 / n to (n-1) / n. In FIG. 10, the value of q can be 1/4, 2/4, and 3/4.

When it is determined that the divided voltage of the i-th second terminal is q in times of V _in , it can be further determined that the j-th battery from the negative electrode in the series-connected battery pack works in a balanced manner in each battery of the series-connected battery pack. The positive electrode voltage is also Q times V _in . At this time, the i-th second terminal can be connected to the positive electrode of the j-th battery through a battery to form an i-th equalization branch. The working principle of the i-th equalizing branch is the same as the working principle of the equalizing branch in the embodiment shown in FIG. 2, and details are not described herein again.

By providing a plurality of equalization branches, the voltage equalization circuit provided in this embodiment can further improve the effect of equalizing the cells in the series battery pack.

Optionally, when the voltage divider circuit of the voltage equalization circuit provides multiple second ends, the power consumption circuit can be connected to any second end of the voltage divider circuit, as shown in FIG. Switch the second end of the connection.

Optionally, on the basis of the embodiment shown in FIG. 10, a corresponding first switch may be added to each equalization branch. When the j-th battery in the series battery pack has an open circuit fault, the first switch in the balanced branch connected to the positive electrode of the j-th to n-th battery in the series battery pack needs to be opened. Optionally, it is also possible to keep only the balanced branch of the positive connection of the positive electrode of the first j-1 battery that is closest to the jth battery.

Optionally, a second switch may be provided on the equalization branch circuit with the smallest divided voltage. Referring to FIG. 10, a second switch may be provided in parallel with the first battery at the rightmost end of the third equalization branch. When the first battery has an open circuit fault, the second switch needs to be closed, and all the first switches are controlled to open. When the other batteries in the series battery pack except the first battery open circuit failure, keep the second switch open.

The embodiment of the present application further provides a voltage equalization circuit, specifically taking n = 2 and m = 1 as an example, the control circuit in the foregoing embodiment controls the first switch and the second switch by way of example. FIG. 11 is a schematic structural diagram of a voltage equalization circuit provided in Embodiment 6 of the present application. As shown in FIG. 11, when n = 2 and m = 1, the series battery pack 20 includes two batteries, battery 1 and battery 2. The positive electrode of battery 1 is connected to the negative electrode of battery 2, the negative electrode of battery 1 is the negative electrode of battery pack 20 in series, and the positive electrode of battery 1 is the positive electrode of battery pack 20 in series. The positive electrode of the battery 1 is connected to the second terminal of the voltage dividing circuit 11 through a resistor 12 and a first switch. The second switch is provided in parallel with the battery 1. The voltage V _out of the second terminal of the voltage dividing circuit 11 is 1/2 of the voltage V _in of the first terminal of the voltage dividing circuit 11.

In this embodiment, the rated operating voltage of the power consumption circuit 30 is V _in / 2. The power consumption circuit 30 may be connected to the second end of the voltage dividing circuit 11 as shown in FIG. The voltage dividing circuit is connected to the positive electrode of the series battery pack 20.

In this embodiment, when the battery 1 has an open circuit fault, the control circuit 13 controls the first switch to open and the second switch to close. At this time, the power source can still charge the battery 2 directly. When the battery 2 is discharged, the voltage provided by the battery 2 is only half of the voltage provided by the original series battery pack 20, which is just the working voltage required by the power consumption circuit 30. Therefore, the control circuit 13 can The voltage circuit 11 or other newly added voltage dividing circuits work in a through mode, and the battery 2 directly supplies power to the power consumption circuit 30.

In this embodiment, when an open circuit fault occurs in the battery 2, the control circuit 13 controls the first switch to be closed and the second switch to be opened. At this time, the power source charges the battery 2 through the voltage dividing circuit 11 and the resistor 12. When discharging, if the power consumption circuit 30 is connected to the second end of the voltage dividing circuit 11, the battery 1 directly supplies power to the power consumption circuit 30 through the resistor 12, and because the voltage provided by the battery 2 is only the original series battery pack 20 Half of the supplied voltage is therefore not caused to cause the voltage of the power consumption circuit 30 to be too high. During discharge, if the power consumption circuit 30 is connected to the positive electrode of the battery 2 through another newly added voltage dividing circuit, the battery 1 supplies power to the power consumption circuit 30 through the resistor 12, the voltage dividing circuit 11, and other newly added voltage dividing circuits in order, and because The voltage provided by the battery 2 is only half of the voltage provided by the original series battery pack 20, which is just the working voltage required by the power consumption circuit 30. Therefore, the control circuit 13 can control the voltage dividing circuit 11 and other newly-added points. The voltage circuits all work in pass-through mode.

It can be understood that when both the battery 1 and the battery 2 have open circuit faults, the series battery pack 20 cannot perform charging and discharging. The control circuit 13 controls both the first switch and the second switch to be open.

Another aspect of the present application further provides a series battery pack, which includes: n batteries connected in series, and a voltage equalization circuit as in any one of the embodiments of FIG. 2 to FIG. 10 above, where n is an integer greater than 1.

Another aspect of the present application further provides an electronic device, including: a power consumption circuit, a series battery pack, and a voltage balancing power as in any one of the foregoing embodiments of FIG. 2 to FIG. 10. The series battery pack includes n batteries connected in series, n Is an integer greater than 1;

One second end of the voltage dividing circuit of the voltage equalization circuit is connected to the first end of the power consumption circuit, and the second end of the power consumption circuit is grounded.

In the present application, "at least one" means one or more, and "multiple" means two or more. "And / or" describes the association relationship between related objects, and indicates that there can be three kinds of relationships. For example, A and / or B can indicate: A exists alone, A and B exist simultaneously, and B exists alone, where A, B can be singular or plural. The character "/" generally indicates that the related objects are an "or" relationship. "At least one or more of the following" or similar expressions refers to any combination of these items, including any combination of single or plural items. For example, at least one (a), a, b, or c can be expressed as: a, b, c, ab, ac, bc, or abc, where a, b, and c can be single or multiple .

The processors involved in the embodiments of the present application may be general-purpose processors, digital signal processors, application specific integrated circuits, field programmable gate arrays or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, and may implement or The disclosed methods, steps and logic block diagrams in the embodiments of the present application are executed. A general-purpose processor may be a microprocessor or any conventional processor. The steps of the method disclosed in combination with the embodiments of the present application may be directly implemented by a hardware processor, or may be performed by a combination of hardware and software modules in the processor.

The memory involved in the embodiments of the present application may be a non-volatile memory, such as a hard disk (HDD) or a solid-state drive (SSD), etc., and may also be a volatile memory (volatile memory), such as Random-access memory (RAM). The memory is any other medium that can be used to carry or store desired program code in the form of instructions or data structures and can be accessed by a computer, but is not limited thereto.

In the several embodiments provided in this application, it should be understood that the disclosed apparatus and method may be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the unit is only a logical function division. In actual implementation, there may be another division manner. For example, multiple units or components may be combined or Can be integrated into another system, or some features can be ignored or not implemented. In addition, the displayed or discussed mutual coupling or direct coupling or communication connection may be indirect coupling or communication connection through some interfaces, devices or units, which may be electrical, mechanical or other forms.

The units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, may be located in one place, or may be distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the objective of the solution of this embodiment.

In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each of the units may exist separately physically, or two or more units may be integrated into one unit. The above integrated unit may be implemented in the form of hardware, or in the form of hardware plus software functional units.

In various embodiments of the present application, the size of the serial numbers of the above processes does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not deal with the implementation process of the embodiments of the present application. Constitute any limitation.

In each of the foregoing embodiments, it may be implemented in whole or in part by software, hardware, firmware, or any combination thereof. When implemented in software, it may be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, all or part of the processes or functions according to the embodiments of the present application are generated. The computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable devices. The computer instructions may be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another computer-readable storage medium, for example, the computer instructions may be from a website site, computer, server, or data center Transmission by wire (for example, coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (for example, infrared, wireless, microwave, etc.) to another website site, computer, server, or data center. The computer-readable storage medium may be any available medium that can be accessed by a computer or a data storage device such as a server, a data center, and the like that includes one or more available medium integration. The usable medium may be a magnetic medium (for example, a floppy disk, a hard disk, a magnetic tape), an optical medium (for example, a DVD), or a semiconductor medium (for example, a solid state disk (Solid State Disk)).

Claims (10)

1. A voltage equalization circuit is applied to a series battery pack, and the series battery pack includes n batteries in series; characterized in that the voltage equalization circuit includes: a voltage dividing circuit; wherein,

   A first end of the voltage dividing circuit is connected to a positive electrode of the series battery pack, and a second end of the voltage dividing circuit is connected to the mth number from the negative electrode of the series battery pack in the series battery pack through a resistor. The positive electrode of the battery is connected, and the negative electrode of the series battery pack is grounded;

   The voltage of the second terminal of the voltage dividing circuit is m / n times the voltage of the first terminal of the voltage dividing circuit, n is an integer greater than 1, and m is greater than or equal to 1 and less than n. Integer.
2. The voltage equalization circuit according to claim 1, wherein the voltage equalization circuit further comprises: a control circuit and a first switch;

   A second terminal of the voltage dividing circuit is connected to the resistor through the first switch, and the control circuit is connected to a control terminal of the first switch.
3. The voltage equalization circuit according to claim 2, wherein the control circuit is respectively connected to a positive electrode of the series battery pack and a positive electrode of the m-th battery;

   The control circuit is configured to control the first switch to be closed when it is detected that the voltage at the positive electrode of the m-th battery is not equal to m / n times the voltage at the positive electrode of the series battery pack.
4. The voltage equalization circuit according to claim 2 or 3, wherein the voltage equalization circuit further comprises: a second switch;

   One end of the second switch is connected to the positive electrode of the m-th battery, the other end of the second switch is grounded, and the control circuit is respectively controlled by the control end of the second switch and the voltage dividing circuit.端 连接 ； End connection;

   When the impedance of at least one of the first m batteries of the series battery from the negative electrode of the series battery is greater than or equal to a preset threshold, the control circuit controls the first switch to open, and the first The two switches are closed, and when the series battery pack supplies power to the power consumption circuit through the voltage dividing circuit, and the positive voltage of the series battery pack is less than a first preset voltage, the output voltage adjustment of the voltage dividing circuit is controlled Is the same as the input voltage of the voltage dividing circuit.
5. The voltage equalization circuit according to claim 2 or 3, wherein the voltage equalization circuit further comprises: a second switch;

   One end of the second switch is connected to the positive electrode of the m-th battery, the other end of the second switch is grounded, and the control circuit is respectively controlled by the control end of the second switch and the voltage dividing circuit. Terminal connection; the control circuit is respectively connected to the positive electrode of each of the batteries in the series battery pack;

   When the control circuit detects that the voltage of the k-th battery in the series battery pack from the negative electrode of the series battery pack is less than the second preset voltage or the voltage change rate is greater than the preset change rate, if the k Less than or equal to m, controlling the first switch to open, and the second switch is closed; if k is greater than m, controlling the first switch to be closed, and the second switch is open;

   Wherein, the value of k is an integer from 1 to n.
6. The voltage equalization circuit according to any one of claims 1 to 5, wherein the n is equal to two and the m is equal to one.
7. The voltage equalization circuit according to any one of claims 1-6, wherein a first end of the voltage dividing circuit is connected to a positive electrode of an n-th battery of the series battery pack, The negative terminal of the first battery is grounded.
8. The voltage equalization circuit according to claim 1, wherein the voltage dividing circuit comprises p second terminals;

   The voltage of the i-th second terminal of the voltage dividing circuit is q times the voltage of the first terminal of the voltage-dividing circuit, and the i-th second terminal passes a resistance corresponding to the i-th second terminal. Connected to the positive electrode of the j-th battery in the series battery pack from the negative electrode of the series battery pack;

   The p is a positive integer less than n, the value of i is an integer from 1 to p, the value of q is j / n, and j is an integer greater than or equal to 1, and less than n.
9. A series battery pack, comprising: n batteries connected in series, and the voltage equalization circuit according to any one of claims 1-8, wherein n is an integer greater than 1.
10. An electronic device, comprising: the voltage equalization circuit, the power consumption circuit, and a series battery pack according to any one of claims 1 to 8, wherein the series battery pack includes n batteries connected in series, and the n Is an integer greater than 1;

    One second end of the voltage dividing circuit of the voltage equalization circuit is connected to the first end of the power consumption circuit, and the second end of the power consumption circuit is grounded.

Images