Battery pack

Abstract

To provide a battery pack that requires no low-voltage auxiliary battery, and is capable of receiving a power source supply from a battery module having the highest voltage of a large number of battery modules connected in series, performing DC-DC converting thereon, and providing the power source to a control unit on a master board.SOLUTION: A battery pack 100 includes a first battery module 110, a second battery module 120 connected in series with the first battery module, and a master board 130 connected to the first battery module and the second battery module. The master board includes a MUX (Multiplexer) circuit 133 that is connected to a battery module having a relatively higher voltage between the first and second battery modules, a DC-DC converter 134 that is connected to the MUX circuit and performs DC-DC converting, and a control unit 135 that is supplied with a drive power source from the DC-DC converter.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The disclosure relates to a battery pack. [Background technology]

[0002] Typically, an electric vehicle contains a high-voltage battery, such as a lithium-ion battery, and a low-voltage battery, such as a lead-acid battery. The high-voltage battery primarily provides the energy needed to run the electric vehicle, while the low-voltage battery primarily provides the energy needed to power the battery pack system.

[0003] Therefore, in the past, in addition to the additional cost associated with low-voltage batteries, there were also problems with the safety of electric vehicles being reduced due to defects in the low-voltage batteries themselves and fluctuations in the power supply to the vehicle (e.g., power supply voltage drops, jumps, disconnections, noise, and poor connection).

[0004] In particular, there is a high possibility that pack-related history (e.g., battery impedance, battery capacity, data required for life calculation, and user history) stored in the system memory may be lost due to instability of the power supply of the pack master board.

[0005] To solve this problem, there is a method of placing a coin cell inside the master board to supply power to the system memory even when there is no external power supply, but this has the problem that the amount of data that can be stored in the memory is extremely limited due to the limit of the coin cell's output power, and the coin cell also has a short lifespan.

[0006] Alternatively, the power required for system operation can be obtained through the battery module inside the pack, but when the power required for pack system operation is extracted from a specific module in a battery pack with a serial structure between modules, there is a problem of large voltage imbalance between modules.

[0007] Another possible method is to step down the pack voltage from the top module and perform DC-DC conversion to operate it, but with the current trend toward higher pack voltages (e.g., 800V or higher), this method has various problems due to losses caused by reduced efficiency of the DC-DC converter and the voltage resistance limits of the integrated circuits (e.g., rising costs, restrictions on sufficient separation distance, inadequate product lineup for power integrated circuits, etc.).

[0008] The above information disclosed in this Background of the Invention section is intended to enhance the understanding of the background of the invention only and may therefore include information that does not constitute prior art. [Prior art documents] [Patent documents]

[0009] [Patent Document 1] Korean Patent Publication No. 10-2021-0110970 [Patent Document 2] Korean Patent Publication No. 10-2020-0047075 [Patent Document 3] Korean Patent Publication No. 10-2018-0045804 Summary of the Invention [Problem to be solved by the invention]

[0010] The present disclosure provides a battery pack that does not require a low-voltage auxiliary battery, receives power from a battery module having the highest voltage among multiple battery modules connected in series, performs DC-DC conversion, and provides power to a control unit of a master board. [Means for solving the problem]

[0011] An exemplary battery pack according to the present disclosure includes a first battery module; a second battery module connected in series to the first battery module; and a master board electrically connected to each of the first and second battery modules, and the master board may include a first power supply wiring connected to a positive terminal of the first battery module, a second power supply wiring connected to a positive terminal of the second battery module, a MUX (Multiplexer) circuit connected to the first and second power supply wiring and connected to a battery module having a relatively higher voltage among the first and second battery modules, a DC-DC converter connected to the MUX circuit and performing DC-DC conversion, and a control unit provided with a driving power from the DC-DC converter.

[0012] In some examples, the MUX circuit may balance the voltages of the first and second battery modules.

[0013] In some examples, the exemplary battery pack according to the present disclosure may further include a voltage sensor, and the voltage sensor may transmit voltage information of the first and second battery modules to the control unit.

[0014] In some examples, the first and second battery modules may each provide a first voltage, a voltage difference between the first and second battery modules may be a second voltage, and the DC-DC converter may provide a third voltage, wherein the first voltage may be greater than the second voltage and the second voltage may be less than the third voltage.

[0015] In some examples, the first voltage may be in a range of 50V to 70V, the second voltage may be in a range of 1V to 2V, and the third voltage may be in a range of 10V to 14V.

[0016] In some examples, if the voltage of the first battery module is higher than the voltage of the second battery module, the control unit can use the MUX circuit to connect the DC-DC converter to the first battery module to receive power from the first battery module, and if the voltage of the second battery module is higher than the voltage of the first battery module, the control unit can use the MUX circuit to connect the DC-DC converter to the second battery module to receive power from the second battery module.

[0017] In some examples, the MUX circuit may include a first switch coupled to the first power supply wiring; and a second switch coupled to the second power supply wiring, and the control unit may turn on or off the first switch and the second switch.

[0018] In some examples, the DC-DC converter may include a primary capacitor connected in parallel between the first power supply wiring and the second power supply wiring; a primary winding connected in parallel between the first power supply wiring and the second power supply wiring; a switching element connected between the primary winding and the second power supply wiring; a secondary winding electromagnetically coupled to the primary winding; a rectifier diode connected to one end of the secondary winding; and a secondary capacitor connected in parallel to one end and the other end of the secondary winding, and the control unit may control the switching element in a PWM manner. Effect of the Invention

[0019] The present disclosure provides a battery pack in which a pack system controller selects a battery module having the highest voltage among a plurality of battery modules and receives power required to drive the pack system controller from the battery module, thereby eliminating the need for a low-voltage auxiliary battery as in the prior art.

[0020] In addition, the present disclosure provides a battery pack in which balancing between multiple battery modules is automatically performed by receiving power from a battery module having the highest voltage among multiple battery modules, and therefore does not require a conventional manual or active cell balancing circuit. [Brief description of the drawings]

[0021] [Figure 1] FIG. 1 is a block diagram illustrating a configuration of an exemplary battery pack according to the present disclosure. [Diagram 2] FIG. 2 is a circuit diagram illustrating the configuration of a MUX circuit and a DC-DC converter in an exemplary battery pack according to the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0022] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0023] The present disclosure is provided to more completely explain the present invention to those skilled in the art, and the following examples may be modified into various other forms, and the scope of the present invention is not limited to the following examples. Rather, these examples are provided to make the present disclosure more faithful and complete, and to fully convey the idea of ​​the present invention to those skilled in the art.

[0024] In the following drawings, the thickness and size of each layer are exaggerated for convenience and clarity of description, and the same reference numerals refer to the same elements in the drawings. As used herein, the term "and / or" includes any one and all combinations of one or more of the corresponding listed items. In addition, in the present specification, "connected" means not only when member A and member B are directly connected, but also when member A and member B are indirectly connected with member C interposed between them.

[0025] The terms used in this specification are used to describe specific embodiments and are not intended to limit the present invention. As used in this specification, the singular form can include the plural form unless the context clearly dictates otherwise. Also, as used in this specification, "comprise", "include" and / or "comprising", "including" specify the presence of a referenced feature, number, step, operation, member, element, and / or group, but do not exclude the presence or addition of one or more other features, numbers, operations, members, elements, and / or groups.

[0026] In this specification, the terms first, second, etc. are used to describe various members, parts, regions, layers, and / or portions, but it is clear that these members, parts, regions, layers, and / or portions should not be limited by these terms. These terms are used only to distinguish one member, part, region, layer, or portion from another region, layer, or portion. Thus, a first member, part, region, layer, or portion detailed below can refer to a second member, part, region, layer, or portion without departing from the teachings of the present invention.

[0027] Space-related terms such as "beneath," "below," "lower," "above," and "upper" may be used to facilitate understanding of one element or feature from another element or feature illustrated in the drawings. Such space-related terms are used to facilitate understanding of the present invention in various process or use states of the present invention, and are not intended to limit the present invention. For example, when an element or feature in the drawing is turned over, an element or feature described as "beneath" or "below" becomes "upper" or "above." Thus, "beneath" is a concept that encompasses "upper" or "below."

[0028] The controller and / or other associated devices or components of the present disclosure may be implemented using any suitable hardware, firmware (e.g., application specific semiconductors), software, or a suitable combination of software, firmware, and hardware. For example, the various components of the controller and / or other associated devices or components of the present disclosure may be formed on a single integrated circuit chip or on separate integrated circuit chips. The various components of the controller may be implemented on a flexible printed circuit film, tape carrier package, printed circuit board, or the same substrate as the controller. The various components of the controller may be processes or threads executed by one or more processors in one or more computing devices, which may execute computer program instructions and interact with other components to perform various functions as described below. The computer program instructions are stored in a memory that may be executed by the computing device using standard memory devices such as random access memory. The computer program instructions may also be stored in other non-transitory computer readable media, such as CD-ROMs, flash drives, and the like. Additionally, those skilled in the art to which the present invention pertains should recognize that functionality of various computing devices may be combined with one another or integrated into a single computing device, or functionality of a particular computing device may be distributed across one or more other computing devices without departing from exemplary embodiments of the present invention.

[0029] 1 is a block diagram illustrating a configuration of an exemplary battery pack 100 according to the present disclosure. As illustrated in FIG. 1, the exemplary battery pack 100 according to the present disclosure may include a first battery module 110, a second battery module 120, a master board 130, and a slave board 140.

[0030] In some examples, the battery module may further include a first battery module to an Nth battery module (where N is a natural number ranging from 2 to 1000). In some examples, the master board 130 may be electrically / mechanically coupled to any one of the multiple battery modules, and the slave board 140 may be electrically / mechanically coupled to the remaining battery modules.

[0031] In the following, an example in which the master board 130 is coupled to the first battery module 110 and the slave board 140 is coupled to the second battery module 120 will be described.

[0032] All the remaining battery modules except the first battery module 110 are defined as second battery modules 120. In the following description, the first battery module 110 and the second battery module 120 are defined as the two battery modules most adjacent to each other.

[0033] The first battery module 110 may include a number of battery cells 111. In some examples, the number of battery cells 111 may be connected in series and / or parallel. In some examples, the battery cells 111 may include or be referred to as lithium ion batteries, lithium ion polymer batteries, lithium iron phosphate batteries, or solid-state batteries. In some examples, the first battery module 110 may provide a DC voltage of about 50V to about 70V, preferably about 60V. In some examples, the first battery module 110 may further include a voltage sensor (not shown) and a sensing wiring 112 for sensing a cell voltage and / or a module voltage. In some examples, the first battery module 110 may be defined as a concept including a number of battery cells 111 and a master board 130.

[0034] The second battery module 120 may include a number of battery cells 121. In some examples, the second battery module 120 may further include a voltage sensor (not shown) and a sensing wiring 122 for sensing a cell voltage and / or a module voltage. The second battery module 120 may be substantially configured the same as or similar to the first battery module 110. In some examples, the slave board 140 may be electrically coupled to the master board 130, and the slave board 140 may be communicatively coupled to the master board 130. In some examples, the second battery module 120 may be defined as a concept including a number of battery cells 121 and the slave board 140.

[0035] In some examples, the first and second battery modules 110, 120 may each provide a first DC voltage, and for example, the first DC voltage may range from about 50 V to about 70 V. In some examples, a voltage difference between the first and second battery modules 110, 120 may be a second DC voltage, and for example, the second DC voltage may range from about 1 V to about 2 V.

[0036] In some examples, the first battery module 110 and the second battery module 120 may be electrically connected in series and / or parallel through the bus bar 151.

[0037] In some examples, the pack negative terminal 152 may be electrically connected to the negative terminal of the first battery module 110, and the pack positive terminal 153 may be electrically connected to the positive terminal of the second battery module 120.

[0038] In some examples, a negative relay 154 may be coupled between the pack negative terminal 152 and the first battery module 110 , and a positive relay 155 may be coupled between the pack positive terminal 153 and the second battery module 120 .

[0039] The master board 130 may include first and second power supply wirings 131 and 132 , a MUX (Multiplexer) circuit 133 , a DC-DC converter 134 , and a control unit 135 .

[0040] In some examples, the master board 130 may further include a data acquisition unit 137, a timer 138, and a relay controller 139. In some examples, the voltage sensor and the sensing wiring 112 may be treated as components of the master board 130.

[0041] The first power supply wiring 131 is connected to the positive terminal of the first battery module 110 and can transmit the highest voltage of the first battery module 110 to the MUX circuit 133. The second power supply wiring 132 is connected to the positive terminal of the second battery module 120 and can transmit the highest voltage of the second battery module 120 to the MUX circuit 133. In some examples, if there are N battery modules, the number of power supply wirings may also be N.

[0042] In some examples, the second power wiring 132 of the second battery module 120 may be electrically coupled to the master board 130 via the slave board 140. In some examples, the power wiring may include or be referred to as the top voltage line of the module. In some examples, the first and second power wirings 131, 132 may further include a printed circuit board pattern and a connector. In some examples, the first and second power wirings 131, 132 may be electrically coupled to the MUX circuit 133 of the master board 130 through a connector, respectively.

[0043] The MUX circuit 133, which will be described again below, is electrically connected to the first and second power supply wirings 131 and 132 and can select the battery module having a relatively higher voltage from among the first and second battery modules 110 and 120.

[0044] In some examples, the MUX circuit 133 may be electrically connected to a battery module having a relatively higher voltage among the first and second battery modules 110 and 120, thereby allowing the power source of the battery module having the relatively higher voltage to be provided to the control unit 135.

[0045] In some examples, the MUX circuit 133 may be connected to a battery module having a relatively higher voltage to consume power, allowing inter-module balancing to proceed naturally. In other words, a battery module having a relatively higher voltage may provide power to the control unit 135 and consume power, thereby allowing the voltage balance of the multiple battery modules in the battery pack 100 to be maintained.

[0046] The DC-DC converter 134 is connected to the MUX circuit 133 and can convert the power supplied from the selected battery module and provide the converted power to the control unit 135. In some examples, the DC-DC converter 134 can include or be referred to as a flyback converter or an LLC resonant converter. In some examples, the DC-DC converter 134 can provide a third DC voltage to the control unit 135, and for example, the third DC voltage can be in the range of about 10V to about 14V.

[0047] The control unit 135 can perform various control operations by receiving driving power from the DC-DC converter 134. The control unit 135 may include or be referred to as an integrated circuit, a microcomputer, a microcontroller, a controller, or a semiconductor chip.

[0048] A voltage sensor (not shown) can sense the cell voltage and / or the module voltage and transmit it to the master board 130 via the sensing wiring 112. In some examples, the voltage sensor can transmit the voltage of an individual battery cell and / or the module voltage to the data acquisition unit 137 via the sensing wiring 112.

[0049] The data acquisition unit 137 may acquire the cell voltage and / or the module voltage by being coupled to the sensing wiring 112. In some examples, the data acquisition unit 137 may include or be referred to as an analog front end.

[0050] The timer 138 can provide a reference clock necessary for the operation of the control unit 135 .

[0051] The relay controller 139 can control the negative relay 154 and / or the positive relay 155 according to a control command from the control unit 135 .

[0052] The slave board 140 may also include a data acquisition section 147. In some examples, the voltage sensor and the sensing wiring 122 may be treated as components of the slave board 140.

[0053] In some examples, the data acquired by the data acquisition unit 147 may be transmitted to the control unit 135 of the master board 130 through a communication line. In some examples, the slave board 140 may include a printed circuit board pattern that transmits the highest voltage of the battery module to the MUX circuit 133 of the master board 130. In other words, the slave board 140 may include a printed circuit board pattern to which a power supply wiring is connected.

[0054] In this manner, in the battery pack 100 according to the present disclosure, the control unit 135 can confirm the voltages of the first battery module 110 and the second battery module 120 received by the data acquisition unit 137 of the master board 130 and the data acquisition unit 147 of the slave board 140.

[0055] Accordingly, the control unit 135 can receive power by connecting the DC-DC converter 134 to the battery module having a higher voltage among the first and second battery modules 110 and 120 using the MUX circuit 133. Meanwhile, the battery module having the highest voltage during the operation of the battery pack 100 can be changed at any time, and each time, the control unit 135 operates a switch provided in the MUX circuit unit 133 to connect the DC-DC converter 134 to the battery module having the highest voltage.

[0056] In this manner, in the present disclosure, the master board 130 can receive the power required for its own operation from the battery module to which the master board 130 is coupled or the battery module to which the slave board 140 is coupled.

[0057] Furthermore, in the present disclosure, the master board 130 (i.e., the control unit 135) receives power from the battery module having the relatively highest voltage, thereby allowing module balancing within the battery pack 100 to be automatically performed.

[0058] In addition, in the present disclosure, a battery pack 100 having an independent power source without a lead-acid battery (low-voltage battery or auxiliary battery) is provided, so that a separate pack voltage sensor and / or module voltage sensor may be omitted, thereby reducing costs associated with installing sensors.

[0059] In addition, compared to a conventional structure in which the power required for the system is supplied from outside the pack system, the battery pack 100 according to the present disclosure can maintain a permanently woken-up state. Therefore, for example, the system power source can be operated continuously regardless of whether the electric vehicle is operating or not, and therefore, the battery pack 100 can be continuously monitored and the history of the pack operation status can be continuously stored.

[0060] FIG. 2 is a circuit diagram illustrating the configuration of the MUX circuit 133 and the DC-DC converter 134 of the exemplary battery pack 100 according to the present disclosure.

[0061] As described above, if the voltage of the first battery module 110 is higher than the voltage of the second battery module 120, the control unit 135 uses the MUX circuit 133 to connect the DC-DC converter 134 to the first battery module 110 to receive power from the first battery module 110, and if the voltage of the second battery module 120 is higher than the voltage of the first battery module 110, the control unit 135 uses the MUX circuit 133 to connect the DC-DC converter 134 to the second battery module 120 to receive power from the second battery module 120.

[0062] To this end, the MUX circuit 133 may include a first switch 1311 and a second switch 1312. The first switch 1311 may be electrically coupled to the first power supply wiring 131. In other words, the first switch 1311 may be electrically coupled to the first battery module 110 via the first power supply wiring 131. The second switch 1312 may be electrically coupled to the second power supply wiring 132. In other words, the second switch 1312 may be electrically coupled to the second battery module 120 via the second power supply wiring 132.

[0063] In some examples, a large number of first switches 1311 may be provided in parallel, and a large number of second switches 1312 may also be provided in parallel. Therefore, the operation of the present disclosure may be implemented even if another battery module is present between the first and second battery modules 110, 120. In other words, even if the first and second battery modules 110, 120 are not adjacent to each other but are far apart, the operation of the present disclosure may be implemented as described above or similarly.

[0064] The control unit 135 may turn on or off the first switch 1311 and the second switch 1312. In some examples, the first switch 1311 and the second switch 1312 may include or be referred to as a metal-oxide-semiconductor field-effect transistor (MOSFET) or an insulated-gate bipolar transistor (IGBT).

[0065] The DC-DC converter 134 may include a primary capacitor C1, a primary winding N1, a switching element 1313, a secondary winding N2, a rectifier diode D1, and a secondary capacitor C2. The primary capacitor C1 may be connected in parallel between the first power supply wiring 131 and the second power supply wiring 132. The primary winding N1 may be connected in parallel between the first power supply wiring 131 and the second power supply wiring 132. In other words, the primary winding N1 may be connected in parallel to the primary capacitor C1. The switching element 1313 may be connected between the primary winding N1 and the second power supply wiring 132. The secondary winding N2 may be electromagnetically coupled to the primary winding N1. The rectifier diode D1 may be connected to one end of the secondary winding N2, and the secondary capacitor C2 may be connected in parallel to one end and the other end of the secondary winding N2. In some examples, the switching element 1313 may also include or be referred to as a MOSFET or an IGBT.

[0066] In this manner, the control unit 135 controls the switching element 1313 in a PWM (pulse width modulation) manner, so that the energy stored in the primary winding N1 is transferred to the secondary winding N2, and ultimately, a smooth DC voltage can be provided to the control unit 135 by the operation of the rectifier diode D1 and the secondary capacitor C2.

[0067] In this manner, the MUX circuit 133 and the DC-DC converter 134 can simultaneously perform module balancing and power supply operations.

[0068] For example, when the control unit 135 determines that the voltage of the first battery module 110 is higher than the voltage of the second battery module 120, it turns on all of the first switch 1311 and the second switch 1312 of the MUX circuit unit 133, and then controls the switching element 1313 of the DC-DC converter 134 in a PWM manner. Then, the energy of the first battery module 110, which has a relatively high voltage, is transferred to the second battery module 120, which has a relatively low voltage, through the first switch 1311, the primary side capacitor C1, and the primary side winding N1, and a part of the energy is transferred to the secondary side winding N2. In addition, a rectified DC voltage may be supplied to the control unit 135 by the smoothing operation of the rectifier diode D1 and the secondary side capacitor C2 of the DC-DC converter 134. In other words, the MUX circuit 133 and the DC-DC converter 134 can simultaneously perform a module balancing operation and a power supply operation to the control unit 135.

[0069] What has been described above is merely one embodiment for implementing an exemplary battery pack according to the present disclosure, and the present invention is not limited to the above embodiment. It can be said that the technical spirit of the present invention is within the scope of the following claims to the extent that anyone having ordinary skill in the art to which the invention pertains can make various modifications without departing from the gist of the present invention. [Explanation of symbols]

[0070] 100; An exemplary battery pack according to the present disclosure 110: First battery module 111; Battery cell 112;Sensing wiring 120; Second battery module 121; Battery cell 122;Sensing wiring 130; Master Board 131;1st power supply wiring 132;Second power supply wiring 133;MUX circuit 1311; First switch 1312; Second switch 134: DC-DC converter C1: Primary side capacitor N1: Primary winding 1313: Switching element N2: Secondary winding D1: Rectifier diode C2: Secondary capacitor 135; Control section 137; Data Acquisition Section 138; Timer 139;Relay controller 140;Slave board 146:Sensing wiring 147; Data Acquisition Section 151; Busbar 152; Pack negative terminal 153; Pack positive terminal 154: Negative relay 155; Positive relay

Claims

1. A first battery module; a second battery module connected in series to the first battery module; and a master board electrically connected to each of the first and second battery modules; The master board includes a battery pack including: a first power supply wiring connected to a positive terminal of the first battery module; a second power supply wiring connected to a positive terminal of the second battery module; a MUX (Multiplexer) circuit connected to the first and second power supply wirings and connected to a battery module having a relatively higher voltage of the first and second battery modules; a DC-DC converter connected to the MUX circuit for DC-DC conversion; and a control unit provided with a driving power supply from the DC-DC converter.

2. 2. The battery pack according to claim 1, wherein the MUX circuit maintains voltage balancing of the first and second battery modules.

3. The battery pack of claim 1 , further comprising a voltage sensor, the voltage sensor transmitting voltage information of the first and second battery modules to the controller.

4. 2. The battery pack of claim 1, wherein the first and second battery modules each provide a first voltage, a voltage difference between the first and second battery modules is a second voltage, and the DC-DC converter provides a third voltage, the first voltage being greater than the second voltage and the second voltage being less than the third voltage.

5. 5. The battery pack of claim 4, wherein the first voltage is in a range of 50V to 70V, the second voltage is in a range of 1V to 2V, and the third voltage is in a range of 10V to 14V.

6. The control unit is If the voltage of the first battery module is higher than the voltage of the second battery module, the DC-DC converter is connected to the first battery module using the MUX circuit to receive power from the first battery module; 2. The battery pack of claim 1, wherein if a voltage of the second battery module is higher than a voltage of the first battery module, the DC-DC converter is connected to the second battery module using the MUX circuit to receive power from the second battery module.

7. The MUX circuit a first switch coupled to the first power supply line; and a second switch coupled to the second power supply line; The battery pack according to claim 6 , wherein the control unit turns on or off the first switch and the second switch.

8. The DC-DC converter a primary side capacitor connected in parallel between the first power supply wiring and the second power supply wiring; a primary winding connected in parallel between the first power supply wiring and the second power supply wiring; a switching element coupled between the primary winding and the second power supply wiring; a secondary winding electromagnetically coupled to the primary winding; a rectifier diode coupled to one end of the secondary winding; and a secondary capacitor connected in parallel to one end and the other end of the secondary winding, The battery pack according to claim 7 , wherein the control unit controls the switching element in a PWM manner.

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