Battery management device and method

Abstract

A battery management device according to one embodiment of the present invention is for controlling the charging of an electrically connectable first battery and a second battery, and includes a measuring unit configured to measure the voltage of the first battery, and a control unit configured to compare the voltage of the first battery with a preset target voltage, and to charge the second battery using the first battery if the voltage of the first battery is equal to or greater than the target voltage.

Description

Technical Field

[0001] The present invention relates to a battery management device and method, and more particularly, to a battery management device and method for controlling the charging of a plurality of electrically connectable batteries.

[0002] This application claims priority based on Korean Patent Application No. 10-2023-0122033 filed on September 13, 2023, and all of the content disclosed in the specification and drawings of the application is incorporated into this application.

Background Art

[0003] Recently, the demand for portable electronic products such as notebook computers, video cameras, and mobile phones has increased rapidly, and with the full-scale development of electric vehicles, energy storage batteries, robots, satellites, etc., research on high-performance batteries capable of repeated charging and discharging has been actively conducted.

[0004] Currently commercially available batteries include nickel-cadmium batteries, nickel-metal hydride batteries, nickel-zinc batteries, lithium batteries, etc. Among these, lithium batteries are in the spotlight because they have almost no memory effect compared to nickel-based batteries, so they can be freely charged and discharged, have a very low self-discharge rate, and have a high energy density.

[0005] With the commercialization of electric power drive devices such as electric vehicles, electric motorcycles, and electric bicycles, the demand for high-capacity and high-performance batteries is increasing. However, it has been emphasized that the time required for battery charging increases as the battery capacity increases. To solve such problems, the demand for technology for rapidly charging batteries is increasing. For example, in order to achieve rapid charging within 15 minutes, a current of 4C or more must be applied.

[0006] Generally, when a charging current of 4C (C-rate) or higher is applied to graphite-based batteries for rapid charging, the likelihood of lithium plating increases significantly. Here, lithium plating (Li-plating) is the phenomenon in which lithium metal is deposited on the surface of the negative electrode. Lithium plating causes side reactions with the electrolyte and / or changes in the kinetic balance of the battery, leading to battery degradation. Furthermore, the deposition of lithium metal on the negative electrode surface can cause an internal short circuit in the battery, posing a risk of ignition and explosion due to the short circuit.

[0007] On the other hand, silicon-based batteries have the advantage of being significantly less prone to lithium plating than graphite-based batteries, even when a charging current of 4C or more for rapid charging is applied. This is because silicon-based batteries have a high energy density and are non-directional, so even with rapid charging, the likelihood of lithium plating occurring is significantly lower compared to graphite-based batteries.

[0008] On the other hand, graphite-based batteries have far superior lifespan characteristics in terms of charge and discharge compared to silicon-based batteries, which is why silicon-based batteries are never used alone. For example, when both graphite-based and silicon-based batteries perform slow charging and discharging, the degradation of the graphite-based battery occurs more slowly than that of the silicon-based battery.

[0009] Furthermore, silicon-based batteries have inferior post-charge storage characteristics compared to graphite-based batteries. Specifically, silicon-based batteries have the characteristic of accelerating degradation if they are not used for a long period after charging. Also, silicon-based batteries have the characteristic of accelerating degradation if stored in a near-fully charged state. This is due to the high reactivity of silicon-based materials.

[0010] Therefore, it is necessary to develop technology that enables rapid battery charging while preventing accelerated battery degradation by considering the lifespan characteristics corresponding to charging and discharging. [Overview of the Initiative] [Problems that the invention aims to solve]

[0011] The present invention has been made to solve the above problems, and aims to provide a battery management device and method that enables rapid charging of batteries while preventing accelerated battery degradation by taking into account the life characteristics corresponding to charging and discharging.

[0012] Other objectives and advantages of the present invention can be understood from the following description and will be understood more clearly from the embodiments of the present invention. Furthermore, it will be readily understood that the objectives and advantages of the present invention can be achieved by the means and combinations thereof set forth in the claims. [Means for solving the problem]

[0013] A battery management device according to one aspect of the present invention is for controlling the charging of an electrically connectable first battery and a second battery, and may include a measuring unit configured to measure the voltage of the first battery, and a control unit configured to compare the voltage of the first battery with a preset target voltage, and, if the voltage of the first battery is equal to or greater than the target voltage, to charge the second battery using the first battery.

[0014] The control unit may be configured to charge the second battery using the first battery if the voltage of the battery is equal to or greater than the target voltage and the first battery is not in a charged state.

[0015] The control unit may be configured to charge the second battery using the first battery if the voltage of the first battery is above the critical voltage and below the target voltage, and the first battery has not been used for a predetermined period of time.

[0016] The control unit may be configured to electrically isolate the second battery when the first battery is in a charged state.

[0017] The control unit may be configured to terminate the charging of the second battery when the voltage of the first battery reaches a preset first reference voltage during the charging process of the second battery using the first battery.

[0018] The measuring unit may be configured to further measure the voltage of the second battery.

[0019] The control unit may be configured to terminate the charging of the second battery when the voltage of the second battery reaches a preset second reference voltage during the charging process of the second battery using the first battery.

[0020] The first battery and the second battery may be configured such that their negative electrode active materials are different from each other.

[0021] A battery pack according to another aspect of the present invention may include a battery management device according to one aspect of the present invention.

[0022] An automobile according to yet another aspect of the present invention may include a battery management device according to one aspect of the present invention.

[0023] Another aspect of the battery management method according to the present invention relates to a battery charging method for a first battery and a second battery, and includes a measurement step of measuring the voltage of the first battery, a voltage comparison step of comparing the voltage of the first battery with a preset target voltage, and a charging step of charging the second battery using the first battery when the voltage of the first battery is greater than or equal to the target voltage.

Advantages of the Invention

[0024] According to one aspect of the present invention, since charging and discharging are controlled in consideration of the life characteristics of the battery regarding energy storage after charging, there is an advantage that acceleration of battery deterioration can be prevented.

[0025] Also, according to one aspect of the present invention, since charging and discharging are controlled in consideration of the characteristics of the battery regarding the charging speed, there is an advantage that the possibility of lithium plating occurring on the battery can be reduced.

[0026] The effects of the present invention are not limited to the effects mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art from the description of the claims.

[0027] The following drawings attached to this specification illustrate desirable embodiments of the present invention and serve to further understand the technical idea of the present invention together with the detailed description of the invention. Therefore, the present invention should not be construed as being limited only to the matters described in the drawings.

Brief Description of the Drawings

[0028] [Figure 1] It is a diagram schematically showing the configurations of a first battery, a second battery, and a battery management device. [Figure 2] It is a diagram referred to for explaining the situation of charging the second battery using the first battery. [Figure 3] It is a diagram schematically showing the situation where a charging current flows into the first battery. [Figure 4] This figure is referenced to illustrate a first embodiment in which charging of the second battery is completed based on the voltage of the first battery. [Figure 5] This figure is referenced to illustrate a second embodiment in which charging of the second battery is terminated based on the voltage of the second battery. [Figure 6] This figure shows an exemplary configuration of a battery pack including a battery management device according to one embodiment of the present invention. [Figure 7] This figure shows an exemplary configuration of a battery pack including a battery management device according to one embodiment of the present invention. [Figure 8] This figure shows an exemplary configuration of a battery pack including a battery management device according to one embodiment of the present invention. [Figure 9] This figure schematically shows an automobile according to another embodiment of the present invention. [Figure 10] This figure schematically illustrates a battery management method according to another embodiment of the present invention. [Modes for carrying out the invention]

[0029] Preferred embodiments of the present invention will be described in detail below with reference to the attached drawings. Prior to this, terms and words used in this specification and in the claims shall not be interpreted in their usual and dictionary sense, but rather in a sense and concept appropriate to the technical idea of ​​the present invention, in accordance with the principle that the inventor himself may appropriately define the concept of terms in order to best describe the invention.

[0030] Therefore, it should be understood that the configurations shown in the embodiments described herein represent only one of the most preferred embodiments of the present invention and do not represent the entire technical concept of the present invention, and that there are various equivalents and modifications that can be substituted therein at the time of filing this application.

[0031] Furthermore, when describing the present invention, if it is determined that a specific description of a related known configuration or function would obscure the gist of the invention, such detailed description will be omitted.

[0032] Terms that include ordinal numbers, such as "first," "second," etc., are used to distinguish one of the various components from the rest, and are not used to limit the components by such terms.

[0033] Throughout the specification, when a part of it is said to "include" a certain component, this means, unless otherwise stated, that it may include other components rather than excluding them.

[0034] Furthermore, throughout the specification, when one part is described as being "connected" to another part, this includes not only cases where they are "directly connected," but also cases where they are "indirectly connected" to each other through other elements.

[0035] Preferred embodiments of the present invention will be described in detail below with reference to the attached drawings.

[0036] Figure 1 is a schematic diagram showing the configuration of the first battery 11, the second battery 12, and the battery management device 100. Referring to Figure 1, the battery management device 100 may include a measuring unit 110 and a control unit 120.

[0037] The battery management device 100 may be a device that controls the charging of the electrically connected first battery 11 and second battery 12.

[0038] The first battery 11 and the second battery 12 may be configured such that their negative electrode active materials are different from each other. For example, the first battery 11 may be a silicon-based battery and the second battery 12 may be a graphite-based battery. For example, the negative electrode active material of the first battery 11 may be 100% silicon, a mixture of silicon and a silicon compound (e.g., SiO and / or SiC), or a mixture of silicon and graphite. For example, the negative electrode active material of the second battery 12 may be 100% graphite, a mixture of graphite and a silicon compound (e.g., SiO and / or SiC), or a mixture of graphite and silicon.

[0039] The measuring unit 110 may be configured to measure the voltage of the first battery 11.

[0040] Specifically, the measuring unit 110 can be connected to the positive and negative terminals of the first battery 11. The measuring unit 110 can measure the positive and negative voltages of the first battery 11 and measure the voltage of the first battery 11 based on the measured positive and negative voltages. For example, the measuring unit 110 can be connected to the positive and negative terminals of the first battery 11 and measure the voltage across both ends of the first battery 11.

[0041] The measuring unit 110 may be connected to the control unit 120 in a communicative manner. That is, the measuring unit 110 may be connected to the control unit 120 in a manner that allows it to transmit electrical signals to the control unit 120 or to receive electrical signals from the control unit 120.

[0042] The control unit 120 may be configured to compare the voltage of the first battery 11 with a preset target voltage.

[0043] Here, the target voltage is the minimum voltage required to charge the second battery 12 using the first battery 11, and is a preset voltage. For example, the target voltage may be preset as a voltage corresponding to an SOC (State of Charge) of 80% or more of the first battery 11. Preferably, the target voltage may be preset as a voltage corresponding to an SOC of 90% or more of the first battery 11.

[0044] For example, the control unit 120 can compare the magnitude of the voltage of the first battery 11 received from the measurement unit 110 with the target voltage.

[0045] If the voltage of the first battery 11 is equal to or greater than the target voltage, the control unit 120 may be configured to charge the second battery 12 using the first battery 11.

[0046] Specifically, the control unit 120 can charge the second battery 12 using the first battery 11 by electrically connecting the first battery 11 and the second battery 12 so that the current output from the first battery 11 flows into the second battery 12. In other words, the discharge current of the first battery 11 can be the charging current of the second battery 12.

[0047] Figure 2 is a diagram referenced to illustrate the situation in which the second battery 12 is charged using the first battery 11.

[0048] In the embodiment shown in Figure 2, the current output from the first battery 11 flows into the second battery 12. As a result, the first battery 11 is discharged and the second battery 12 is charged.

[0049] Generally, the post-charge storage characteristics of silicon-based batteries are inferior to those of graphite-based batteries. For example, silicon-based batteries have the characteristic of accelerating degradation when stored in a near-fully charged state. This is due to the high reactivity of silicon-based materials. On the other hand, graphite-based batteries do not experience accelerated degradation simply because they are stored in a near-fully charged state.

[0050] The battery management device 100 according to the present invention can control the charging and discharging of a battery, taking into account the battery's lifespan characteristics regarding energy storage after charging. By charging the first battery 11 first and then using the first battery 11 to charge the second battery 12, it is possible to prevent the first battery 11 from being stored in a state close to fully charged. This prevents the deterioration of the first battery 11 from accelerating.

[0051] On the other hand, the control unit 120 provided in the battery management device 100 may selectively include a processor, ASIC (application-specific integrated circuit), other chipsets, logic circuits, registers, communication modems, data processing devices, etc., known in the art, in order to execute various control logics performed in the present invention. Furthermore, when the control logic is implemented in software, the control unit 120 can be implemented as a collection of program modules. In this case, the program modules are stored in memory and can be executed by the control unit 120. The memory may be located inside or outside the control unit 120 and may be connected to the control unit 120 by various well-known means.

[0052] The battery management device 100 may further include a storage unit 130. The storage unit 130 can store data and programs necessary for each component of the battery management device 100 to perform its operation and function, or data generated during the process of executing its operation and function. The storage unit 130 is not particularly limited in type, as long as it is a known information storage means that is known to be able to record, erase, update, and read data. Examples of information storage means may include RAM, flash memory, ROM, EEPROM, registers, etc. The storage unit 130 can also store program code that defines the processes that can be executed by the control unit 120.

[0053] For example, the memory unit 130 can store voltages that can be compared with the voltage of the first battery 11. Specifically, the memory unit 130 can store a preset target voltage. The control unit 120 can also access the memory unit 130 and obtain information about the target voltage from it.

[0054] Specifically, when the voltage of the first battery 11 is equal to or greater than the target voltage and charging of the first battery 11 is complete, the control unit 120 may be configured to use the first battery 11 to charge the second battery 12.

[0055] Generally, due to the characteristics of batteries, charging and discharging do not occur simultaneously. Therefore, once the charging of the first battery 11 is complete, the control unit 120 can use the first battery 11 to charge the second battery 12.

[0056] For example, when the voltage of the first battery 11 reaches a predetermined charging termination value, charging of the first battery 11 may be terminated. In this case, the control unit 120 can use the first battery 11 to charge the second battery 12. Here, the charging termination value can be set in advance to a value equal to or greater than the target voltage.

[0057] As another example, when the voltage of the first battery 11 reaches the target voltage, the control unit 120 can terminate the charging of the first battery 11. The control unit 120 can also use the first battery 11 to charge the second battery 12.

[0058] The battery management device 100 according to the present invention has the advantage of being able to control the charging of the first battery 11 and the second battery 12, taking into account the poor post-charge storage characteristics of the first battery 11. Therefore, it is possible to effectively prevent the deterioration of the first battery 11 from accelerating.

[0059] Figure 3 is a schematic diagram showing the situation in which charging current flows into the first battery 11.

[0060] Referring to Figure 3, a charging current flows into the first battery 11, allowing the first battery 11 to be charged.

[0061] In one embodiment, when the first battery 11 is being charged, the control unit 120 may be configured to electrically isolate the second battery 12.

[0062] Here, the statement that the second battery 12 is electrically isolated may mean that the second battery 12 is in an unloaded state.

[0063] Specifically, while the first battery 11 is being charged by a charging current, the charging current does not flow into the second battery 12. In other words, while the first battery 11 is being charged, the second battery 12 may be in an unloaded state.

[0064] Generally, when a charging current of 4C or more for rapid charging is applied to graphite-based batteries, the likelihood of lithium plating increases significantly. On the other hand, silicon-based batteries have the advantage that the likelihood of lithium plating is significantly lower than that of graphite-based batteries, even when a charging current of 4C or more for rapid charging is applied. This is because silicon-based batteries have a high energy density and are non-directional. In other words, in the case of slow charging, the likelihood of lithium plating is low even when silicon-based batteries and graphite-based batteries are charged simultaneously. However, in the case of rapid charging, the likelihood of lithium plating is higher for graphite-based batteries when silicon-based batteries and graphite-based batteries are charged simultaneously.

[0065] For example, when the first battery 11 is rapidly charged, lithium plating may occur in the second battery 12 when the charging current flows into the second battery 12. Therefore, the control unit 120 can prevent lithium plating from occurring in the second battery 12 by electrically isolating the second battery 12 while the first battery 11 is rapidly charged.

[0066] On the other hand, when the first battery 11 is being charged slowly, if charging current flows into the second battery 12, both the first battery 11 and the second battery 12 can be charged simultaneously. If the second battery 12 reaches full charge before the first battery 11, the current output from the first battery 11 cannot flow into the second battery 12. In other words, the second battery 12 cannot be charged using the first battery 11. In this case, since the voltage of the first battery 11 is maintained above the target voltage, the degradation of the first battery 11 may accelerate. Therefore, the control unit 120 can prevent the degradation of the first battery 11 from accelerating by electrically isolating the second battery 12 while the first battery 11 is being charged slowly and charging the second battery 12 using the first battery 11.

[0067] The control unit 120 can isolate the second battery 12 when the first battery 11 is being charged, regardless of the charging pattern (slow charging or fast charging).

[0068] The battery management device 100 according to the present invention can control the charging and discharging of the first battery 11 and the second battery 12, taking into consideration the poor post-charge storage characteristics of the first battery 11 and the possibility of lithium plating occurring in the second battery 12.

[0069] If the voltage of the first battery 11 is above the critical voltage and below the target voltage, and the first battery 11 has not been used for a predetermined period of time, the control unit 120 may be configured to charge the second battery 12 using the first battery 11.

[0070] Generally, the post-charge storage characteristics of silicon-based batteries are inferior to those of graphite-based batteries. For example, silicon-based batteries have the characteristic of accelerating degradation if they are not used for a long period after charging. This is due to the high reactivity of silicon-based materials. On the other hand, graphite-based batteries do not experience accelerated degradation simply because they are not used for a long period after charging and are storing energy.

[0071] If the voltage of the first battery 11 is above the critical voltage and below the target voltage, and the first battery 11 has not been used for a predetermined period of time, the battery management device 100 can prevent the first battery 11 from being unused for a long period of time after charging by using the first battery 11 to charge the second battery 12. This further prevents the deterioration of the first battery 11 from accelerating.

[0072] The following describes embodiments in which the control unit 120 terminates the charging of the second battery 12. Specifically, a first embodiment in which the charging of the second battery 12 is terminated will be described using Figure 4, and a second embodiment in which the charging of the second battery 12 is terminated will be described using Figure 5.

[0073] Figure 4 is a diagram referenced to illustrate a first embodiment in which charging of the second battery 12 is completed based on the voltage of the first battery 11. Figure 4 is a graph showing the voltage of the first battery 11 over time.

[0074] During the charging process of the second battery 12 using the first battery 11, the control unit 120 may be configured to terminate the charging of the second battery 12 when the voltage of the first battery 11 reaches a preset first reference voltage (RV1).

[0075] Here, the first reference voltage (RV1) can be preset to a value smaller than the target voltage (TV) value.

[0076] Referring to Figure 4, t1 is the time when charging of the second battery 12 using the first battery 11 begins, and t2 is the time when charging of the second battery 12 using the first battery 11 ends. V1 is the voltage of the first battery 11 at t1. That is, V1 is the voltage of the first battery 11 at the time when charging of the second battery 12 using the first battery 11 begins.

[0077] Specifically, at t1, the voltage of the first battery 11 is equal to or greater than the target voltage (TV). t2 is the point at which the voltage of the first battery 11 reaches the first reference voltage (RV1). At t2, charging of the second battery 12 using the first battery 11 is completed. During the charging process of the second battery 12 using the first battery 11, the first battery 11 is discharged, and therefore the voltage of the first battery 11 decreases.

[0078] Figure 5 is a diagram referenced to illustrate a second embodiment in which charging of the second battery 12 is completed based on the voltage of the second battery 12. Figure 5 is a graph showing the voltage of the second battery 12 over time.

[0079] The measuring unit 110 may be configured to further measure the voltage of the second battery 12.

[0080] Specifically, the measuring unit 110 may be connected to the positive and negative terminals of the second battery 12. The measuring unit 110 can measure the positive and negative voltages of the second battery 12 and measure the voltage of the second battery 12 based on the measured positive and negative voltages. For example, the measuring unit 110 can be connected to the positive and negative terminals of the second battery 12 and measure the voltage across both ends of the second battery 12.

[0081] During the charging process of the second battery 12 using the first battery 11, the control unit 120 may be configured to terminate the charging of the second battery 12 when the voltage of the second battery 12 reaches a preset second reference voltage (RV2).

[0082] Referring to Figure 5, t3 is the time when charging of the second battery 12 using the first battery 11 begins, and t4 is the time when charging of the second battery 12 using the first battery 11 ends. V2 is the voltage of the second battery 12 at t3. That is, V2 is the voltage of the second battery 12 at the time when charging of the second battery 12 using the first battery 11 begins.

[0083] Specifically, t4 is the point at which the voltage of the second battery 12 reaches the second reference voltage (RV2). During the charging process of the second battery 12 using the first battery 11, the voltage of the second battery 12 increases as the second battery 12 is charged.

[0084] The battery management device 100 according to the present invention can be applied to a BMS (Battery Management System). That is, the BMS according to the present invention can include the battery management device 100 described above. In such a configuration, at least a portion of each component of the battery management device 100 can be realized by complementing or adding functions of components included in a conventional BMS. For example, the measurement unit 110, the control unit 120, and the storage unit 130 of the battery management device 100 can be realized as components of a BMS.

[0085] Furthermore, the battery management device 100 according to the present invention may be provided on the battery pack 10. That is, the battery pack 10 according to the present invention may include the above-described battery management device 100 and one or more battery cells. The battery pack 10 may further include electrical components (relays, fuses, etc.) and a case.

[0086] Figures 6 to 8 show an exemplary configuration of a battery pack 10 including a battery management device 100 according to one embodiment of the present invention.

[0087] The positive terminals of the first battery 11 and the second battery 12 are connected to the positive terminal P+ of the battery pack 10, and the negative terminals of the first battery 11 and the second battery 12 may be connected to the negative terminal P- of the battery pack 10. In addition, a load or charger 20 may be connected to the positive terminal P+ and negative terminal P- of the battery pack 10.

[0088] The control unit 120 may be connected to the charger 20 by wire and / or wirelessly. For example, in the case of a wired connection, the control unit 120 may be connected to the charger 20 via a communication terminal (not shown). Specifically, one end of the communication terminal may be connected to the control unit 120 and the other end may be connected to the charger 20.

[0089] Specifically, Figure 7 is a schematic diagram showing a first embodiment of the battery pack 10.

[0090] Referring to Figure 7, the battery pack 10 may include a first battery 11, a second battery 12, a battery management device 100, a first relay R1, and a second relay R2.

[0091] The first relay R1 may be configured to connect between the first battery 11 and the second battery 12 and the positive terminal P+ of the battery pack 10. For example, one end of the first relay R1 may be connected to the positive terminals of the first battery 11 and the second battery 12. The other end of the first relay R1 may be connected to the positive terminal P+ of the battery pack 10.

[0092] The control unit 120 can control the operating state of the first relay R1. Depending on the controlled operating state, the first relay R1 may be configured to electrically connect or disconnect the first battery 11 and the second battery 12 with the positive terminal P+ and the negative terminal P- of the battery pack 10. When the operating state of the first relay R1 is in the turn-on state, the first battery 11 and the second battery 12 may be electrically connected with the charger 20. Conversely, when the operating state of the first relay R1 is in the turn-off state, the electrical connection between the first battery 11 and the second battery 12 and the charger 20 may be disconnected.

[0093] The second relay R2 may be configured to connect between the first battery 11 and the second battery 12. For example, one end of the second relay R2 may be connected between the positive terminal of the first battery 11 and one end of the first relay R1. The other end of the second relay R2 may be connected to the positive terminal of the second battery 12. Specifically, the second battery 12 may be connected to the first relay R1 via the second relay R2. That is, when the second relay R2 is turned off, the electrical connection between the second battery 12 and the first relay R1 may be interrupted.

[0094] The control unit 120 can control the operating state of the second relay R2. The second relay R2 may be configured to electrically connect or disconnect the first battery 11 and the second battery 12 depending on the controlled operating state. When the operating state of the second relay R2 is in the turn-on state, the second battery 12 and the first battery 11 may be electrically connected. Conversely, when the operating state of the second relay R2 is in the turn-off state, the electrical connection between the second battery 12 and the first battery 11 may be disconnected.

[0095] When charging the second battery 12 using the first battery 11, the control unit 120 can control the first relay R1 to the turn-off state and the second relay R2 to the turn-on state. This disconnects the electrical connection between the first battery 11 and the second battery 12 and the charger 20. The first battery 11 and the second battery 12 can be electrically connected.

[0096] When charging the first battery 11, the control unit 120 can control the first relay R1 to the turn-on state. In other words, the first battery 11 and the charger 20 can be electrically connected.

[0097] When the second battery 12 is electrically isolated while the first battery 11 is being charged, the control unit 120 can control the first relay R1 to the turn-on state and the second relay R2 to the turn-off state.

[0098] When the charging of the second battery 12 using the first battery 11 is to be terminated, the control unit 120 can switch the operating state of the second relay R2 from the turn-on state to the turn-off state.

[0099] Specifically, Figure 8 is a schematic diagram showing a second embodiment of the battery pack 10.

[0100] Referring to Figure 8, the second embodiment is an embodiment that further includes a capacitor 13, a third relay R3, and a fourth relay R4 in addition to the configuration of the first embodiment. That is, the battery pack 10 may include a first battery 11, a second battery 12, a battery management device 100, a first relay R1, a second relay R2, a third relay R3, a fourth relay R4, and a capacitor 13.

[0101] The battery pack 10 may be configured to allow the first battery 11, the second battery 12, and the capacitor 13 to be connected in parallel.

[0102] For example, one end of the third relay R3 may be connected to the positive terminal of the first battery 11 and one end of the first relay R1. The other end of the third relay R3 may be connected to one end of the capacitor 13 and one end of the fourth relay R4.

[0103] One end of the fourth relay R4 may be connected to the other end of the third relay R3 and one end of the capacitor 13. The other end of the fourth relay R4 may be connected to the other end of the second relay R2 and the positive terminal of the second battery 12.

[0104] One end of capacitor 13 may be connected to the other end of the third relay R3 and one end of the fourth relay R4. The other end of capacitor 13 may be connected to the negative terminal of the first battery 11, the negative terminal of the second battery 12, and the negative terminal P- of the battery pack 10.

[0105] When charging the second battery 12 using the first battery 11, the first battery 11 can be discharged to charge the capacitor 13, and the capacitor 13 can be discharged to charge the second battery 12. In other words, the charging current of the capacitor 13 is the discharge current of the first battery 11, and the discharge current of the capacitor 13 is the charging current of the second battery 12.

[0106] When the first battery 11 is discharged to charge the capacitor 13, the control unit 120 can control the third relay R3 to the turn-on state and the fourth relay R4 to the turn-off state. That is, the first battery 11 and the capacitor 13 are electrically connected, and the electrical connection between the second battery 12 and the capacitor 13 can be disconnected. On the other hand, in this case, whether or not there is an electrical connection between the first battery 11 and the charger 20, and whether or not there is an electrical connection between the second battery 12 and the charger 20, is irrelevant to the charging of the capacitor 13 using the first battery 11.

[0107] When discharging capacitor 13 to charge the second battery 12, the control unit 120 can control the fourth relay R4 to the turn-on state and the third relay R3 to the turn-off state. In other words, the second battery 12 and capacitor 13 are electrically connected, and the electrical connection between the first battery 11 and capacitor 13 can be disconnected. On the other hand, in this case, whether or not there is an electrical connection between the first battery 11 and the charger 20, and whether or not there is an electrical connection between the second battery 12 and the charger 20, is irrelevant to charging the second battery 12 using capacitor 13.

[0108] When charging the first battery 11, the control unit 120 can control the first relay R1 to the turn-on state. In other words, the first battery 11 and the charger 20 can be electrically connected.

[0109] When the second battery 12 is electrically isolated while the first battery 11 is being charged, the control unit 120 can control the first relay R1 to the turned-on state and the second relay R2 and the fourth relay R4 to the turned-off state. In other words, the first battery 11 and the charger 20 are electrically connected, while the second battery 12 can be electrically disconnected from the charger 20 and the capacitor 13.

[0110] When the charging of the second battery 12 using the capacitor 13 is terminated, the control unit 120 can switch the operating state of the fourth relay R4 from the turn-on state to the turn-off state.

[0111] The embodiments for charging the first battery 11 and the second battery 12 have been described above using Figures 7 and 8. However, it should be noted that various embodiments that can derive substantially the same functions as the battery pack 10 described above can be applied to the battery pack 10 including the battery management device 100 according to the present invention.

[0112] Figure 9 is a schematic diagram showing an automobile 1 according to another embodiment of the present invention.

[0113] Referring to Figure 9, the battery pack 10 according to an embodiment of the present invention may be included in an automobile 1 such as an electric vehicle (EV) or a hybrid vehicle (HV). The battery pack 10 can drive the automobile 1 by supplying power to the motor via an inverter provided in the automobile 1. Here, the battery pack 10 may include a battery management device 100. That is, the automobile 1 may include a battery management device 100.

[0114] Figure 10 is a schematic diagram illustrating a battery management method according to another embodiment of the present invention. Referring to Figure 10, the battery management method may include a measurement step (S100), a voltage comparison step (S200), and a charging step (S300).

[0115] Specifically, the battery management method is a method for controlling the charging of an electrically connectable first battery 11 and a second battery 12. Preferably, each step of the battery management method can be performed by a battery management device 100. The following explanation will omit or briefly describe any content that overlaps with the above.

[0116] The measurement step (S100) is a step of measuring the voltage of the first battery 11, and can be performed by the measurement unit 110.

[0117] Specifically, the measuring unit 110 is connected to the positive and negative terminals of the first battery 11, and can measure the voltage across both ends of the first battery 11.

[0118] The voltage comparison step (S200) is a step in which the voltage of the first battery 11 is compared with a preset target voltage, and can be performed by the control unit 120.

[0119] Specifically, the control unit 120 can compare the voltage of the first battery 11 with the target voltage to determine whether the voltage of the first battery 11 is equal to or greater than the target voltage.

[0120] The charging step (S300) is a step in which the first battery 11 is used to charge the second battery 12 when the voltage of the first battery 11 is equal to or greater than the target voltage, and this can be performed by the control unit 120.

[0121] Specifically, the control unit 120 can charge the second battery 12 using the first battery 11 by electrically connecting the first battery 11 and the second battery 12 so that the current output from the first battery 11 flows into the second battery 12.

[0122] The embodiments of the present invention described above are not limited to apparatus and methods, but can also be realized by a program that implements functions corresponding to the configuration of the embodiments of the present invention, or by a recording medium on which such a program is recorded. Such implementation can be easily carried out by experts in the technical field to which the present invention belongs, based on the description of the embodiments described above.

[0123] Although the present invention has been described above with reference to limited embodiments and drawings, it goes without saying that the present invention is not limited thereto, and various modifications and variations are possible within the equivalent scope of the technical idea of ​​the present invention and the claims described below by persons with ordinary skill in the art to which the present invention pertains.

[0124] Furthermore, the present invention described above can be substituted, modified, and altered in various ways by a person with ordinary skill in the art to which the present invention belongs, without departing from the technical spirit of the invention. Therefore, it is not limited to the embodiments described above and the accompanying drawings, and all or part of each embodiment can be selectively combined to form various modifications. [Explanation of Symbols]

[0125] 1: Automobile 10: Battery Pack 11: First Battery 12: Second Battery 100: Battery management device 110: Measuring part 120: Control Unit 130: Storage section

Claims

1. A battery management device that controls the charging of electrically connected first and second batteries, A measuring unit configured to measure the voltage of the first battery, A control unit is configured to compare the voltage of the first battery with a preset target voltage, and if the voltage of the first battery is equal to or greater than the target voltage, to charge the second battery using the first battery. A battery management device, including a battery management device.

2. The control unit, The battery management device according to claim 1, wherein when the voltage of the first battery is equal to or greater than the target voltage and charging of the first battery is completed, the device is configured to charge the second battery using the first battery.

3. The control unit, The battery management device according to claim 1, wherein if the voltage of the first battery is above the critical voltage and below the target voltage, and the first battery has not been used for a predetermined period of time, the device is configured to charge the second battery using the first battery.

4. The control unit, The battery management device according to claim 1, configured to electrically insulate the second battery when the first battery is being charged.

5. The control unit, The battery management device according to claim 1, wherein, during the charging process of the second battery using the first battery, the charging of the second battery is terminated when the voltage of the first battery reaches a preset first reference voltage.

6. The aforementioned measuring unit is The voltage of the second battery is further measured, The control unit, The battery management device according to claim 1, configured to terminate charging of the second battery when the voltage of the second battery reaches a preset second reference voltage during the charging process of the second battery using the first battery.

7. The first battery and the second battery are The battery management device according to claim 1, wherein the negative electrode active materials are configured to be different from each other.

8. A battery pack comprising a battery management device, a first battery, and a second battery according to any one of claims 1 to 7.

9. An automobile comprising a battery management device according to any one of claims 1 to 7.

10. A battery management method for controlling the charging of electrically connected first and second batteries, A measurement step of measuring the voltage of the first battery, A voltage comparison step of comparing the voltage of the first battery with a preset target voltage, If the voltage of the first battery is equal to or greater than the target voltage, a charging step is performed to charge the second battery using the first battery, Battery management methods, including those mentioned above.

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