Battery comprising supercapacitor

Abstract

The present invention relates to the technical field of batteries. Disclosed is a battery comprising a supercapacitor. The battery comprises a chemical battery module and a supercapacitor module; the chemical battery module and the supercapacitor module are connected in series by means of a switch module; the chemical battery module comprises one or more battery cells; the supercapacitor module comprises one or more supercapacitor cells; the chemical battery module, the supercapacitor module, and the switch module are all connected to a controller; and by means of the switch module and on the basis of the actual condition of the internal parameters of a battery pack, the controller controls the chemical battery module and the supercapacitor module to be connected in series to jointly supply power to the external, or to be disconnected in series, and the chemical battery module supplies power to the external. The circuit in the present invention has simple and reliable structure, is practical, and is convenient to popularize and apply.

Description

A battery containing a supercapacitor Technical Field

[0001] The present invention relates to the technical field of batteries, and in particular to a battery containing a supercapacitor. Background Art

[0002] When a load is heavy, the discharge current of batteries such as lithium batteries, lead-acid batteries, and other chemical batteries is large, causing the battery voltage to drop below the minimum voltage required by the load. This means that there is a short-term high-power output requirement and a high output voltage requirement. At this time, the output voltage of the battery alone cannot meet the load voltage requirement. In a low-temperature environment, the internal resistance of the battery increases significantly, and the battery cannot meet the short-term power demand with a high output voltage requirement. To address these situations, additional battery capacity redundancy is currently required, such as by significantly increasing the number of unnecessary battery cells, which increases the battery's volume, weight, and cost.

[0003] Summary of the Invention

[0004] The present invention provides a battery containing a supercapacitor, which includes a chemical battery pack and a supercapacitor pack. When the output voltage does not meet or is predicted to not meet the load requirements, the chemical battery pack is automatically connected in series with the internal supercapacitor pack to increase the battery output voltage to meet the minimum operating voltage requirements of the load. This eliminates the need to set additional battery capacity redundancy, effectively reduces the volume and weight of the battery, and achieves a minimized battery configuration.

[0005] The present invention can be achieved through the following technical solutions:

[0006] A battery containing a supercapacitor, comprising a chemical battery pack and a supercapacitor pack, both of which are connected in series via a switch module, wherein the chemical battery pack comprises one or more battery cells, and the supercapacitor pack comprises one or more supercapacitor cells.

[0007] The chemical battery pack, supercapacitor pack, and switch module are all connected to a controller. The controller controls the chemical battery pack and the supercapacitor pack to be connected in series through the switch module according to the actual internal parameters of the battery, so that they can jointly supply power to the outside, or cuts off the series connection between the chemical battery pack and the supercapacitor pack, so that the chemical battery pack can supply power to the outside.

[0008] Furthermore, the switch module includes a first switch and a second switch, one end of the chemical battery pack is connected to one end of the supercapacitor pack through the first switch, the other end of the supercapacitor pack is connected to one end of the load, and the other end of the load is connected to the other end of the chemical battery pack;

[0009] One end of the second switch is connected to one end of the chemical battery pack, and the other end is connected to the other end of the supercapacitor pack.

[0010] Furthermore, the other end of the chemical battery pack is also connected to one end of the supercapacitor pack through a charging circuit, and the charging circuit is used to charge the supercapacitor pack.

[0011] Furthermore, the internal parameters of the battery include battery pack temperature, chemical battery pack charge SOC, chemical battery pack aging SOH, battery voltage and battery discharge current. Corresponding thresholds are set, and judgment conditions are constructed based on each internal parameter being less than the corresponding threshold. The five judgment conditions are combined. If any combination is met, the supercapacitor group and the chemical battery group are controlled to be connected in series through the switch module, otherwise the series connection of the supercapacitor group and the chemical battery group is cut off.

[0012] Furthermore, the multiple supercapacitor cells in the supercapacitor group are connected in series, in parallel, or in a series-parallel hybrid.

[0013] The beneficial technical effects of the present invention are as follows:

[0014] The supercapacitor group and the chemical battery group are connected in series via a switch module to form a battery for external power supply. When the output voltage of the chemical battery group does not meet or is predicted to not meet the load requirements, the chemical battery group is automatically connected in series with the internal supercapacitor group, and the minimum operating voltage requirement of the load is met by increasing the working mode of the battery output voltage. This eliminates the need for additional battery capacity redundancy, effectively reduces the volume and weight of the battery, and achieves a minimized battery configuration. The circuit structure of the present invention is simple and reliable, practical and convenient, and easy to promote and apply. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] FIG1 is a block diagram of the overall circuit structure of the present invention;

[0016] FIG2 is a schematic diagram of current flow when MOSFETs are used as the first switch and the second switch in a specific embodiment of the present invention, wherein the right side is the boost mode and the left side is the exit boost mode. DETAILED DESCRIPTION

[0017] The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0018] As shown in Figure 1, the present invention provides a battery containing a supercapacitor, including a chemical battery pack and a supercapacitor pack, the two of which are connected in series through a switch module, the chemical battery pack includes one or more battery cells, the supercapacitor pack includes one or more supercapacitor cells, the chemical battery pack, the supercapacitor pack, and the switch module are all connected to a controller, and the controller controls the chemical battery pack and the supercapacitor pack to be connected in series through the switch module according to the actual situation of the internal parameters of the battery, so that they can jointly supply power to the outside, or cut off the chemical battery pack and the supercapacitor pack from being connected in series, so that the chemical battery pack can supply power to the outside. In this way, the supercapacitor pack and the chemical battery pack are selectively connected in series through the switch module to make up for the insufficient voltage of the chemical battery pack itself to meet the voltage requirements of the external load instead of expanding the battery pack capacity by adding more redundant cells, reducing the volume and weight of the battery, and realizing a minimized battery configuration. After testing, it was found that if a pure lithium iron phosphate battery is prepared, a 40Ah battery pack is required to meet the requirements. However, the battery pack structure of the present invention only requires a 20Ah battery pack plus a 330F supercapacitor to meet the requirements. The weight of the battery pack can be reduced to about 2 / 3 to 1 / 2 of the original, the volume can be reduced to about 2 / 3 of the original, and the cost can be reduced to 1 / 2.

[0019] The details are as follows:

[0020] The switch module includes a first switch and a second switch. One end of the chemical battery pack is connected to one end of the supercapacitor pack through the first switch, the other end of the supercapacitor pack is connected to one end of the load, and the other end of the load is connected to the other end of the chemical battery pack; one end of the second switch is connected to one end of the chemical battery pack, and the other end is connected to the other end of the supercapacitor pack.

[0021] The first switch and the second switch can be other switching elements such as MOSFET tubes, IGBTs, relays, etc., among which MOSFET tubes and IGBTs can use special switch driver chips, which communicate with these switch driver chips through the controller. The switch driver chip drives the first switch and the second switch to be on and off to realize whether the supercapacitor group is connected in series into the loop. For the voltage increase of the chemical battery group, it is also possible to directly control the input of the switch driver chip by designing a pure hardware control circuit to control the on and off of the first switch and the second switch. In addition, if the first switch and the second switch use relay-type switching elements, it is necessary to design a corresponding switch control module, which receives the control instructions of the controller or is directly driven by the controller to realize the control of whether the supercapacitor group is connected in series into the loop.

[0022] A storage capacitor is also connected between the other end of the supercapacitor group and the other end of the chemical battery group. The two ends of the energy storage capacitor are also connected in parallel to the two ends of the load. The other end of the chemical battery group is also connected to one end of the supercapacitor group through a charging circuit. The charging circuit is used to charge the supercapacitor group.

[0023] The charging circuit can be implemented using a current-limited buck circuit, or other charging circuits such as a bidirectional DCDC charging and discharging circuit with limitations, a charging circuit composed of a resistor and a switch (limitations include current limiting, voltage limiting, or current and voltage limiting), etc. When the supercapacitor group is not working, it is charged to the maximum voltage required under the current working conditions. The setting of the maximum voltage is obtained by considering factors such as the vehicle's operating status, battery pack status, and ambient temperature. The supercapacitor group can be charged by a chemical battery pack through a charging circuit, or by load feedback.

[0024] In addition, the target charging voltage that can be set for the supercapacitor group is related to the ambient temperature monitored by the battery pack. The higher the ambient temperature, the lower the target charging voltage that can be set, thereby extending the life of the supercapacitor group.

[0025] The multiple supercapacitor cells in the supercapacitor group can be connected in series, in parallel, or in a series-parallel hybrid.

[0026] Considering that there may be a short blank period in the circuit during the current path switching process, the energy storage capacitor connected in parallel between the chemical battery pack, supercapacitor pack and load can temporarily support the output voltage and reduce the short-term voltage drop of the entire battery pack during the switching process.

[0027] When executing the control of whether the supercapacitor group is connected in series to enter the loop, the controller can monitor multiple internal parameters of the battery such as battery pack temperature, chemical battery group charge SOC, chemical battery group aging SOH, battery voltage and battery discharge current, set corresponding thresholds, and construct judgment conditions based on each internal parameter being less than the corresponding threshold. The five judgment conditions are combined. If any combination is established, the supercapacitor group and the chemical battery group are controlled to be connected in series through the switch module, otherwise the series connection of the supercapacitor group and the chemical battery group is cut off.

[0028] When the controller receives the feedback from various sensors and finds that the chemical battery pack meets the condition to enter the boost control logic, it first controls the second switch to disconnect and remain open through the switch driver chips corresponding to the first switch and the second switch, and then controls the first switch to close and remain closed, connecting the supercapacitor bank in series with the chemical battery pack. At this time, the output voltage of the entire battery pack is jointly provided by the series connection of the supercapacitor bank and the chemical battery pack, thus meeting the minimum operating voltage requirement of the load. Since there will be a state where the first switch and the second switch are both disconnected during the switching control process by the switch driver chips, the energy storage capacitor is used to support the voltage demand for a short time, and the freewheeling circuits of the first switch and the second switch, such as MOSFET transistors, can ensure the normal operation of the battery.

[0029] According to the above analysis, as shown in Figure 2, taking the MOSFET transistor as an example, its switching judgment logic is as follows:

[0030] Initially set the discharge current thresholds as N1 and N2, where N1 < N2, and the voltage thresholds as M1 and M2, where M1 > M2. The initial state of the first switch is open, and the initial state of the second switch is closed. Here, the thresholds N1, N2, M1, and M2 can be adjusted according to the load voltage demand or can also be fixed values. For example, when the discharge demand current is large, the voltage threshold can be increased or decreased.

[0031] a. As shown in the right figure of Figure 2, the battery enters the boost control logic as follows:

[0032] (1) When "the discharge current of the chemical battery pack < N1" and "the voltage of the chemical battery pack < M1", the second switch disconnects and remains open. After the second switch completes the disconnection, the first switch closes and remains closed;

[0033] (2) For any other situation except the above, no action is taken.

[0034] b. As shown in the left figure of Figure 2, the battery exits the boost control logic as follows:

[0035] (1) When "the discharge current of the chemical battery pack > N2", the first switch needs to be disconnected and remain open. After the first switch completes the disconnection, the second switch closes and remains closed;

[0036] (2) When "the voltage of the chemical battery pack - the voltage of the supercapacitor bank > M2", the handling method is the same as that in b(1);

[0037] (3) For any other situation except the above two, no action is taken.

[0038] Although specific embodiments of the present invention are described above, those skilled in the art should understand that these are merely examples and that various changes or modifications may be made to these embodiments without departing from the principles and essence of the present invention. Therefore, the scope of protection of the present invention is limited by the appended claims.

Claims

1. A battery containing a supercapacitor, characterized in that: It includes a chemical battery pack and a supercapacitor pack, which are connected in series through a switch module. The chemical battery pack includes one or more battery cells, and the supercapacitor pack includes one or more supercapacitor cells. The chemical battery pack, supercapacitor pack, and switch module are all connected to a controller. The controller controls the chemical battery pack and the supercapacitor pack to be connected in series through the switch module according to the actual internal parameters of the battery pack so that they can jointly supply power to the outside, or cuts off the series connection between the chemical battery pack and the supercapacitor pack so that the chemical battery pack can supply power to the outside.

2. The battery containing a supercapacitor according to claim 1, characterized in that: The switch module includes a first switch and a second switch, one end of the chemical battery pack is connected to one end of the supercapacitor pack through the first switch, the other end of the supercapacitor pack is connected to one end of the load, and the other end of the load is connected to the other end of the chemical battery pack; One end of the second switch is connected to one end of the chemical battery pack, and the other end is connected to the other end of the supercapacitor pack.

3. The battery containing a supercapacitor according to claim 2, characterized in that: The other end of the chemical battery pack is also connected to one end of the supercapacitor pack through a charging circuit, and the charging circuit is used to charge the supercapacitor pack.

4. The battery containing a supercapacitor according to claim 1, characterized in that: The internal parameters of the battery include battery pack temperature, chemical battery pack charge SOC, chemical battery pack aging SOH, battery voltage and battery discharge current. Corresponding thresholds are set, and judgment conditions are constructed when each internal parameter is less than the corresponding threshold. The five judgment conditions are combined. If any combination is met, the supercapacitor group and the chemical battery group are controlled to be connected in series through the switch module. Otherwise, the series connection of the supercapacitor group and the chemical battery group is cut off.

5. The battery containing a supercapacitor according to claim 4, characterized in that: The multiple supercapacitor cells in the supercapacitor group are connected in series, in parallel, or in a series-parallel hybrid.

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