Method and apparatus for charging battery

Abstract

A method for charging a battery according to one embodiment of the present invention is a method for charging a battery by dividing a charging section into a plurality of charging sections, the method comprising: a first discharging step for applying a first discharge pulse between an n-1th (n is a natural number of 2 or more) charging section and an nth charging section; and a second discharge step of applying a second discharge pulse between the nth charging section and an n+1th charging section. The discharge rate of the second discharge pulse is lower than the discharge rate of the first discharge pulse.

Description

Battery charging method and device

[0001] This application claims priority to Korean Patent Application No. 10-2023-0098508, filed on July 27, 2023, and all contents disclosed in the specification and drawings of the said application are incorporated herein by reference.

[0002] The present invention relates to a battery charging method and device, and more particularly, to a battery charging method and device capable of maximizing the charging efficiency of a battery by applying a discharge pulse during a charging process and differentiating the environment in which the discharge pulse is applied.

[0003] As the demand for portable electronic devices such as laptops, video cameras, and mobile phones that use electricity as a power source rapidly increases, and as mobile robots, electric bicycles, electric carts, and electric vehicles become more widely commercialized, research into high-performance secondary batteries capable of repeated charging and discharging is actively being conducted.

[0004] Commercialized secondary batteries include nickel-cadmium batteries, nickel-metal hydride batteries, nickel-zinc batteries, and lithium secondary batteries. Among these, lithium secondary batteries have the advantage of being able to charge and discharge freely and have a very low self-discharge rate because they have almost no memory effect compared to nickel-based secondary batteries. In addition, they have the characteristics of high energy density and high operating voltage, so they are being studied more intensively than other types of secondary batteries and are being applied more widely in actual products.

[0005] Recently, secondary batteries are widely used not only in small devices such as portable electronic devices, but also in medium and large devices such as electric vehicles and energy storage systems (ESS).

[0006] In this case, a battery module in which a number of electrically connected secondary batteries are housed together inside a module case is mainly applied, and furthermore, when high power or large capacity is required, a battery pack in which a number of such battery modules are electrically connected is also applied.

[0007] Secondary battery cells, cell assemblies, battery modules, or battery packs (hereinafter collectively referred to as "batteries") are important factors for power efficiency and safety, so active research is being conducted on BMS, which monitors the electrical characteristics of batteries and performs feedback control, such as charging and discharging, using the monitoring results.

[0008] Meanwhile, various studies are being conducted on battery charging, including rapid charging, to more effectively reflect user needs and improve the overall environment in line with the increase in battery capacity.

[0009] The methods used to charge batteries include constant current-constant voltage (CC-CV), pulse charging, boost charging, and multi-step CC charging.

[0010] When charging a battery in a high current environment to shorten the charging time, the lithium (Li, lithium) cation (Li+) supplied to the negative electrode may not be quickly absorbed by the negative electrode and accumulate on the negative electrode, precipitating as lithium metal, which may cause a lithium plating phenomenon.

[0011] This phenomenon causes side reactions with the electrolyte and changes in the kinetic balance of the battery, which are the main causes of reduced battery performance, reduced capacity, and even deterioration or reduced lifespan of the battery.

[0012] Additionally, if this phenomenon occurs, non-uniform lithium crystals (Li-dendrite) are formed, which increases the possibility of short circuits, which can lead to fatal safety problems such as fire and explosion.

[0013] The present invention was created to solve the above-described problems in the background described above, and the purpose of the present invention is to provide a battery charging method and device that can fundamentally solve the problem of lithium precipitation by applying a discharge mode that applies a discharge pulse between charging sections divided into a plurality of sections, while differentiating the discharge environment of each discharge mode, and further optimize the charging efficiency such as rapid charging.

[0014] The technical problems to be solved by the present invention are not limited to the problems described above, and other problems not mentioned will be clearly understood by those skilled in the art from the description of the invention described below.

[0015] A battery charging method according to one aspect of the present invention is a method of charging a battery by dividing a charging section into a plurality of charging sections, the method including: a first discharging step of applying a first discharging pulse between an (n-1)th charging section (n is a natural number greater than or equal to 2) and an nth charging section; and a second discharging step of applying a second discharging pulse between the nth and n+1th charging sections.

[0016] The discharge rate of the second discharge pulse may be configured to be less than the discharge rate of the first discharge pulse.

[0017] The time for which the second discharge pulse is applied may be configured to be longer than the time for which the first discharge pulse is applied.

[0018] The discharge rate of the first or second discharge pulse and the time for which the first or second discharge pulse is applied may be set so that the discharge amount of the second discharge step is less than or equal to the discharge amount of the first discharge step.

[0019] The charging rate of the nth charging section may be configured to be lower than the charging rate of the n-1th charging section.

[0020] The charging environment of the above plurality of charging sections can be configured to be variably determined by the SOC value estimated based on the change in characteristic data of the battery according to charging.

[0021] The above charging environment may be at least one of the length of each section of the plurality of charging sections and the charging rate of each section of the plurality of charging sections.

[0022] According to another aspect of the present invention, a battery charging device may include a charging unit configured to charge a battery; a discharging unit configured to discharge the battery; and a control unit configured to control the charging unit so that the battery is charged in a plurality of charging sections, and to control the discharging unit so that a first discharging pulse is applied between an (n-1)th charging section (n is a natural number equal to or greater than 2) and an nth charging section, and a second discharging pulse is applied between the nth and n+1th charging sections.

[0023] The above control unit may be configured to control the discharge unit so that the discharge rate of the second discharge pulse is less than the discharge rate of the first discharge pulse.

[0024] The above control unit may be configured to control the discharge unit so that the time for which the second discharge pulse is applied is longer than the time for which the first discharge pulse is applied.

[0025] The control unit may be configured to control the discharge rate of the first or second discharge pulse and the time for which the first or second discharge pulse is applied so that the discharge amount of the second discharge pulse is less than or equal to the discharge amount of the first discharge pulse.

[0026] The above control unit may be configured to control the charging unit so that the charging environment of the plurality of charging sections is variably set using a preset target SOC.

[0027] The above target SOC can be estimated as the SOC value at which lithium is precipitated based on changes in the characteristic data of the battery according to charging.

[0028] According to the present invention, by dividing the charging into multiple sections and applying discharge processing that applies a discharge pulse between each section of charging, not only can lithium precipitation be minimized, but also precipitated lithium can be removed more effectively.

[0029] In addition, according to one aspect of the present invention, by differentially applying the discharge environment, specifically the time at which the discharge pulse is applied and the discharge rate of the discharge pulse in each sequential discharge processing that proceeds in time series, the charging efficiency such as the shortening of the charging time can be further increased, and the operating performance or durability of the battery can be further improved by delaying or slowing down the aging process of the battery.

[0030] Furthermore, according to one aspect of the present invention, by organically grafting electrical characteristic data of a battery and variably setting the charging environment of each charging section that is divided into multiple sections, a charging environment optimized for the state of the battery that changes over time can be implemented.

[0031] The following drawings attached to this specification illustrate preferred embodiments of the present invention, and together with the detailed description of the invention described below, serve to more effectively understand the technical idea of ​​the present invention, and therefore, the present invention should not be interpreted as being limited to the matters described in these drawings.

[0032] Figure 1 is a block diagram showing a detailed configuration of a battery charging device according to one embodiment of the present invention.

[0033] Figure 2 is a block diagram showing the detailed configuration of the data operation unit.

[0034] Figure 3 is a flowchart explaining a processing process according to one embodiment of the present invention.

[0035] Figure 4 is a flowchart illustrating a processing process according to another embodiment of the present invention.

[0036] Figure 5 is a drawing explaining one example of the discharge rate of the discharge pulse for each discharge section.

[0037] Figure 6 is a drawing explaining one example of the time at which a discharge pulse is applied for each discharge section.

[0038] Figures 7 and 8 are diagrams explaining the time-series characteristics of the discharge environment for each discharge section based on the entire charging process.

[0039] Figure 9 is a drawing explaining the process of determining the SOC at which lithium is precipitated during charging.

[0040] Figure 10 is a diagram showing the performance results of a battery according to an embodiment of the present invention based on the discharge capacity retention rate.

[0041] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings. Prior to this, it should be noted that the terms and words used in this specification and claims should not be construed as limited to their conventional or dictionary meanings. Based on the principle that the inventor can appropriately define the concepts of terms to best explain his or her invention, they should be interpreted in a way that conforms to the technical spirit of the present invention.

[0042] Therefore, the embodiments described in this specification and the configurations illustrated in the drawings are only the most preferred embodiments of the present invention and do not represent all of the technical ideas of the present invention. Therefore, it should be understood that there may be various equivalents and modified examples that can replace them at the time of filing this application.

[0043] In addition, when describing the present invention, if it is determined that a detailed description of a related known configuration or function may obscure the gist of the present invention, the detailed description is omitted.

[0044] Throughout the specification, whenever a part is said to "include" a component, this does not mean that it excludes other components, but rather that it may include other components, unless otherwise stated.

[0045] Additionally, terms such as processor described in the specification mean a unit that processes at least one function or operation, which may be implemented by hardware, software, or a combination of hardware and software.

[0046] Additionally, throughout the specification, when we say that a part is "connected" to another part, this includes not only cases where it is "directly connected" but also cases where it is "indirectly connected" with other elements in between.

[0047]

[0048] FIG. 1 is a block diagram showing a detailed configuration of a battery charging device (100) according to one embodiment of the present invention.

[0049] As illustrated in FIG. 1, the battery charging device (100) of the present invention may be configured to include an interface unit (110), a charging unit (120), a discharging unit (130), a control unit (140), and a detection unit (160).

[0050] Before going into a detailed description of the present invention, it should be noted that the battery charging device (100) of the present invention can be implemented through various combinational applications of electronic devices, parts, etc. (ASIC, chipset, logic circuit, register, communication modem, MCU, etc.) such as storage means, operation processing means, input / output means, etc.

[0051] Therefore, each component of the battery charging device (100) illustrated in FIG. 1 should be understood as a functionally or logically distinct component rather than a physically distinct component.

[0052] That is, since each component illustrated in the above drawing corresponds to a logical configuration for effectively explaining the technical idea of ​​the present invention, even if each component is configured integrated or separated, if the function performed by the logical configuration of the present invention can be realized, it should be interpreted as being within the scope of the present invention, and of course, if it is a component that performs the same or similar function, it should be interpreted as being within the scope of the present invention regardless of whether or not the name is consistent. The data operation unit (150) illustrated in FIG. 2 is also the same.

[0053] In addition, the battery charging method according to the present invention can be implemented as a set or algorithm of processing related to data processing, handling, control, operation, etc., and thus, it can be implemented by a combination of the logical configurations shown in Fig. 1, as well as in the form of software installed and operated on a computer or a terminal, module, etc. equivalent thereto.

[0054] For example, the battery charging method can be applied to a Battery Management System (BMS). When connected to a charging device, the BMS can rapidly charge the battery by controlling the charging and discharging of the battery according to the battery charging method according to an embodiment of the present invention.

[0055] As another example, the battery charging method can be applied to a charging device. The charging device can rapidly charge a battery according to the battery charging method according to an embodiment of the present invention.

[0056] The charging unit (120) of the present invention is electrically connected to the battery (50) and performs charging processing on the battery (50). Depending on the embodiment, as illustrated in FIG. 1, the charging unit (120) of the present invention may be electrically connected to the battery (50) through an interface unit (110) linked to a physical means such as a jack or socket.

[0057] Since various types of secondary battery cells, cell banks, cell assemblies, cell modules, and battery packs can be targets of charging, in the following description, the battery (50) may mean an object that collectively refers to cells, cell banks, cell assemblies, cell modules, and battery packs.

[0058] The discharge unit (130) of the present invention is a configuration that performs discharge targeting a battery (50), and can be electrically connected to the battery (50) through an interface unit (110) like the charging unit (120) described above, and, of course, can be electrically connected to the battery (50) through an interface unit independent of the charging unit (120) depending on the embodiment.

[0059] The control unit (140) of the present invention is configured to be communicatively connected to the charging unit (120) and the discharging unit (130) and to control the charging processing performed by the charging unit (120) and the discharging processing performed by the discharging unit (130).

[0060] The battery charging device (100) according to the present invention is configured to charge the battery (50) by dividing the charging section into k sections (k is a natural number greater than or equal to 2) without performing continuous charging processing from the start of charging to the end of charging (hereinafter referred to as a 'multi-step charge mode').

[0061] The battery charging device (100) according to the present invention divides the charging section into a plurality of charging sections and charges the battery, and is configured to apply a first discharge pulse between the n-1 (n is a natural number greater than or equal to 2)-th charging section and the n-th charging section, and to apply a second discharge pulse between the n-th charging section and the n+1-th charging section.

[0062] However, in one embodiment, the discharge pulse may not always be applied between each charging section. For example, if the first discharge pulse is applied between the (n-1)th and (n)th charging sections, the second discharge pulse may not be applied between the (n)th and (n+1)th charging sections. In addition, the third discharge pulse may be applied between the (n+1)th and (n+2)th charging sections.

[0063] First, the overall charging process performed by the present invention will be described, and the specific details of each discharge mode or discharge processing performed by applying a discharge pulse will be described later.

[0064] FIG. 3 is a flowchart illustrating a charging processing process according to the present invention, and illustrates a charging process based on an example in which the charging section is divided into three.

[0065] When a physical connection is made between the battery (50) and the charging unit (120) (or the interface unit (110)), and charging is initiated (S300) through a method such as inputting an electrical signal or selecting a button or interface for initiating charging, the control unit (140) of the present invention controls the charging unit (120) so that charging is driven according to the charging environment of the first charging section (S310).

[0066] The above charging environment refers to the time during which charging takes place, i.e., one or more of the length of the corresponding charging section, the magnitude of the charging current, and the charging rate. Preferably, the charging environment is configured to be variably set to reflect the current state of the battery (50), as described below. In the case of a multi-stage charging method, it is preferable that the magnitude of the charging current or the charging rate be set to decrease as the charging section progresses.

[0067] When the SOC (State of Charge) of the battery (50) reaches the first target SOC (S320) through the charging of the first charging section (hereinafter referred to as the "first charging"), the first charging is terminated. Depending on the embodiment, the condition for terminating the first charging may be determined by whether the charging voltage of the battery (50) reaches the first threshold voltage, in addition to whether the SOC of the battery (50) reaches the first target SOC as described above.

[0068] Thereafter, the control unit (140) of the present invention controls the discharge unit (130) to drive discharge according to the discharge environment of the first discharge mode for the battery (50) for which the first charge has been completed (S330). The discharge environment refers to at least one of the size of the discharge pulse, the discharge rate of the discharge pulse, or the time for which the discharge pulse is applied.

[0069] When the discharge of the first discharge mode (hereinafter referred to as the 'first discharge') satisfies the first condition (discharge time or current SOC of the battery (50) etc.) set in advance (S340), the control unit (140) of the present invention controls the discharge unit (130) to terminate the first discharge, and then controls the charge unit (120) to initiate the charging of the second charge section (second charge) (S350).

[0070] As previously explained, the second charge is also driven by a charging environment (one or more of the length of the charging section, the size of the charging current, and the charging rate) that is uniquely set for the second charging section itself.

[0071] When the SOC of the battery (50) reaches the second target SOC through charging by the second charge (S360), the control unit (140) of the present invention controls the charging unit (120) to terminate the second charge and controls the discharging unit (130) to drive the discharging according to the discharging environment of the second discharging mode (S370).

[0072] When the discharge in the second discharge mode (hereinafter referred to as the 'second discharge') satisfies the preset second condition (discharge time or current SOC of the battery (50) etc.) (S380), the control unit (140) of the present invention controls the discharge unit (130) to terminate the second discharge and controls the charging unit (120) to initiate the charging of the third and final charging section (third charge) (S390).

[0073] When the SOC of the battery (50) reaches the third target SOC, which is the final target, through charging by the third charge (S395), the entire charging processing according to the present invention is terminated.

[0074] FIG. 3 illustrates a processing process for one embodiment of the present invention. It goes without saying that charging can be performed by dividing the process into more charging sections depending on the embodiment. In this case, when dividing the process into more charging sections, a discharge can be configured to occur between at least two charging sections among each charging section by applying a discharge pulse, and a resting period for a predetermined period of time can be configured to be applied between charging sections where discharge processing is not applied to resolve lithium precipitation.

[0075]

[0076] Figure 4 is a flowchart illustrating a processing process according to another embodiment of the present invention.

[0077] The embodiment of the present invention described above with reference to FIG. 3 corresponds to an embodiment in which charging is performed on a battery (50) that is completely discharged or equivalent thereto, or on a battery (50) corresponding to a lower SOC.

[0078] The embodiment illustrated in FIG. 4 corresponds to an embodiment in which the current SOC of a battery (50) to be charged is determined, and a charging section corresponding to the current SOC of the battery (50) among the charging sections divided into a plurality of sections is set as the charging start section, and charging is performed.

[0079] As described above, when a signal for charging start is input (S400), the detection unit (160) of the present invention determines the current SOC of the battery (50) using the electrical characteristic values ​​(voltage, etc.) of the battery (50) (S410), and outputs the result data to the control unit (140) of the present invention.

[0080] When data on the current SOC of the battery (50) is input, the control unit (140) of the present invention selects a charging section corresponding to the current SOC among a plurality of preset charging sections (S420) and controls the charging section (120) to initiate charging in the charging environment (charging rate, size of charging current, etc.) of the selected charging section (S430).

[0081] After the SOC of the battery (50) reaches the target SOC according to the charging section (S440), if the current charging section in progress is not the last charging section among the preset multiple charging sections (S450), step-by-step charging and discharging processing between charging sections are cyclically performed as described with reference to FIG. 3, etc. (S460).

[0082]

[0083] Fig. 5 is a drawing explaining an example of a discharge rate of a discharge pulse for each discharge section, and Fig. 6 is a drawing explaining an example of a time at which a discharge pulse is applied for each discharge section.

[0084] The embodiment illustrated in Fig. 5 corresponds to an embodiment in which four discharge processes are applied overall based on the SOC of the battery (50) that increases by charging.

[0085] Assuming that discharge processing is not applied after the last charging section, this embodiment may correspond to an embodiment of charging a battery (50) with five or more charging sections. Assuming that discharge processing is applied between the current charging section and the next charging section, the first discharge is applied between the first charge and the second charge, the second discharge is applied between the second charge and the third charge, the third discharge is applied between the third charge and the fourth charge, and finally, the fourth discharge is applied between the fourth charge and the fifth charge based on the time series order of the charging.

[0086] As illustrated in Fig. 5, it is preferable that the discharge rate (C-rate) of the first discharge pulse applied in the first discharge (discharge of the first discharge mode) be set to be the largest, and it is preferable that the discharge rate of the second discharge pulse applied in the second discharge following the first discharge be configured to be smaller than the discharge rate of the first discharge pulse. In addition, it is preferable that the discharge rate of the corresponding discharge mode be configured to gradually decrease as it goes to the third discharge and then the fourth discharge based on the time series order.

[0087] Based on the example of Fig. 5, b (discharge rate of the second discharge) is smaller than a (discharge rate of the first discharge) and larger than c (discharge rate of the third discharge). In addition, it is preferable that d (discharge rate of the fourth discharge) is smaller than c.

[0088] Specifically, it is preferable that the discharge rate of the first discharge pulse applied between the (n-1)th charging section (where n is a natural number greater than or equal to 2) and the nth charging section be configured to be greater than the discharge rate of the second discharge pulse applied between the nth and n+1th charging section. In other words, it is preferable that the discharge rate of the second discharge pulse be configured to be less than the discharge rate of the first discharge pulse.

[0089] When configured in this way, the removal of lithium precipitated by charging in the corresponding charging section can be further accelerated, thereby more effectively suppressing the performance deterioration of the battery (50).

[0090] According to the embodiment, as illustrated in FIG. 6, it is preferable that the discharge time (the time during which the discharge pulse is applied (the time during which the discharge proceeds)) of the subsequent discharge mode be configured to be greater than or equal to the discharge time of the previous discharge mode based on the time series sequence. For example, the discharge time of the current discharge mode may be equal to or greater than the discharge time of the previous discharge mode.

[0091] Based on the example of Fig. 6, T2 (the time for the second discharge to proceed) is longer than T1 (the time for the first discharge to proceed) and shorter than T3 (the time for the third discharge to proceed). In addition, it is preferable that T4 (the time for the fourth discharge to proceed) be configured to be longer than T3. However, although the embodiment of Fig. 6 illustrates an embodiment in which the discharge time of the nth discharge exceeds the discharge time of the n-1th discharge, as explained above, an embodiment in which the discharge time of the nth discharge is equal to the discharge time of the n-1th discharge may also be applied.

[0092] Specifically, it is preferable that the application time of the first discharge pulse applied between the (n-1)th charging section (where n is a natural number greater than or equal to 2) and the nth charging section be configured to be less than or equal to the application time of the second discharge pulse applied between the nth and n+1th charging section. In other words, it is preferable that the application time of the second discharge pulse be configured to be greater than or equal to the application time of the first discharge pulse.

[0093] When configured in this way, the removal of lithium precipitated by charging in the corresponding charging section can be induced more stably, thereby improving the charging efficiency of the battery (50) and effectively suppressing the performance deterioration of the battery (50).

[0094]

[0095] Figures 7 and 8 are diagrams explaining the time-series characteristics of the discharge environment for each discharge section based on the entire charging process.

[0096] In the embodiments of FIGS. 7 and 8, considering the direction of charging progress, it is preferable that the size of the discharge pulse (discharge rate) of the discharge mode be configured to become smaller as it progresses to the subsequent discharge mode.

[0097] In addition, in the embodiments of FIGS. 7 and 8, considering the direction of charge progression, it is preferable that the time for which the discharge pulse of the discharge mode is applied is configured to be the same or longer as it proceeds to the subsequent discharge mode. More preferably, it is preferable that the time for which the discharge pulse is applied is configured to become longer as it proceeds to the subsequent discharge mode.

[0098] Depending on the embodiment, it is preferable that the discharge rate of the discharge pulse and the application time of the corresponding discharge pulse be set so that the discharge amount of each discharge mode is the same or decreases as the subsequent discharge mode proceeds.

[0099] For example, based on the embodiment illustrated in FIG. 7, the discharge amount of the first discharge can be defined by the multiplication operation of the discharge rate (A) of the discharge pulse and the application time (T1) of the discharge pulse, so that the discharge environment (discharge rate of the discharge pulse and application time of the discharge pulse) of each discharge mode can be configured to be set under the condition that the following equation 1 is satisfied.

[0100] [Formula 1]

[0101]

[0102] In this respect, the control unit (140) of the present invention can be configured to control the discharge rate of the first or second discharge pulse and the time for which the first or second discharge pulse is applied so that the discharge amount of the second discharge pulse is less than or equal to the discharge amount of the first discharge pulse.

[0103] As described above, the first discharge pulse refers to a discharge pulse applied between the n-1th (n is a natural number greater than or equal to 2) charging section and the nth charging section, and the second discharge pulse refers to a discharge pulse applied between the nth charging section and the n+1th charging section.

[0104]

[0105] The control unit may be configured to control the charging unit so that the charging environment of multiple charging sections is variably set using a preset target SOC.

[0106] Here, the charging environment of the charging section means one or more of the length of the charging section (the time during which charging is performed), the size of the charging current, and the charging rate.

[0107] Specifically, the target SOC can be estimated as the SOC value at which lithium is precipitated based on changes in the characteristic data of the battery according to charging.

[0108] Fig. 9 is a profile illustrating the relationship between the SOC and voltage of a battery (50) according to charging. Specifically, the embodiment of Fig. 9 is a charging profile showing the corresponding relationship between the SOC and voltage of a battery when the battery is charged using a multi-stage charging method according to an embodiment of the present invention.

[0109] More specifically, an embodiment of the present invention that organically reflects the current state (degeneration level, SOH (State of health), etc.) of a battery (50) and sets multiple charging intervals, etc. will be described in detail.

[0110] Figure 2 is a block diagram showing the detailed configuration of the data operation unit (150).

[0111] Referring to FIG. 2, the data operation unit (150) may be configured to include a data generation unit (151), an estimation unit (153), and an output unit (155), and corresponds to a configuration that estimates the SOC value at which lithium is precipitated during the charging process and outputs data thereon to the control unit (140) of the present invention.

[0112] When the target SOC estimated as the SOC value at which lithium is precipitated is input to the control unit (140), the control unit (140) can variably set the charging environment of multiple charging sections based on the target SOC. In addition, the control unit (140) can control the charging unit (120) and the discharging unit (130) based on the target SOC.

[0113] The data generation unit (151), which is a component of the data operation unit (150), is configured to generate characteristic data of the battery (50) according to charging. The characteristic data may include the voltage of the battery (50), the voltage change rate, the voltage increase rate (slope value), the change rate of the voltage increase rate (change rate of the slope value), etc.

[0114] The target battery (50) for which characteristic data is generated may be a non-degenerated battery (e.g., a BOL (Beginning of life) battery) having specifications equivalent to those of the battery (50) currently being charged, as well as multiple batteries classified by SOH.

[0115] When characteristic data is generated, the estimation unit (153) of the present invention estimates the target SOC (A, FIG. 9) at which lithium is precipitated based on the characteristic data or a change in the characteristic data, and the output unit (155) of the data operation unit (150) outputs the target SOC to the control unit (140). Of course, there may be multiple target SOCs (A) as shown in FIG. 9.

[0116] When the target SOC is input in this manner, the control unit (140) variably sets the points at which the charging environment and discharge mode of the multiple charging sections are applied using multiple target SOCs. It is preferable that the target SOC, as well as the setting data for the charging environment determined by the target SOC, be organized into a database linked to the degradation degree of the battery (50) and utilized.

[0117] In the embodiment of FIG. 1, the data operation unit (150) is described as being included in the battery charging device (100) according to one embodiment of the present invention, but the data operation unit (150) may be configured as a separate device provided externally to the battery charging device (100). In this case, the data operation unit (150) may be connected to the control unit (140) through wired and / or wireless communication, and may transmit information regarding the target SOC to the control unit (140). For example, the data operation unit (150) may be a cloud computing device that estimates the target SOC for each battery by considering the degree of battery deterioration, etc., and stores the estimated target SOC in a database.

[0118]

[0119] Figure 10 is a diagram illustrating the performance results of a battery according to an embodiment of the present invention based on the discharge capacity retention rate. As is well known, a battery has a behavioral characteristic in which its discharge capacity retention rate decreases as use (charging and discharging) continues or is repeated.

[0120] 200 of Fig. 10 is a behavioral characteristic graph of a battery to which only the common condition of charging at a decreasing charge rate (charge current size) as it proceeds to a subsequent charge section is applied. 300 of Fig. 10 is a behavioral characteristic graph of a battery to which the common condition is applied together with the condition of applying a discharge pulse between charge sections, but with the same discharge rate for the same time in all discharge modes. 400 of Fig. 10 is a behavioral characteristic graph of a battery to which the common condition is applied together with the condition of applying a discharge pulse between charge sections, but with the discharge rate becoming smaller and the time for which the discharge pulse is applied becoming longer as it proceeds to a subsequent discharge mode.

[0121] As shown in Fig. 10, in the case of 400, to which processing according to a preferred embodiment of the present invention is applied, it can be confirmed that the durability and performance maintenance rate of the battery (50) itself are clearly improved as the performance deterioration is significantly delayed or slowed down compared to 200 and 300.

[0122]

[0123] Although the present invention has been described above with reference to limited embodiments and drawings, the present invention is not limited thereto, and it is obvious that various modifications and variations are possible within the scope of the technical idea of ​​the present invention and the equivalent scope of the patent claims to be described below by a person having ordinary skill in the art to which the present invention pertains.

[0124] The drawings attached for the purpose of explaining the present invention and illustrating embodiments thereof may be illustrated in a somewhat exaggerated form to emphasize or highlight the technical contents of the present invention. However, it should be interpreted that it is obvious that various modified application examples may be possible at the level of a person skilled in the art in consideration of the contents described above and matters illustrated in the drawings.

[0125] In addition, it is self-evident that expressions such as first, second, upper, lower, or top and bottom in the description of the present invention are merely instrumental conceptual terms used to relatively distinguish each component (element) from each other, and are not terms used to indicate a specific order, priority, etc., or terms used to physically distinguish each component (element) on an absolute basis.

[0126] (Explanation of symbols)

[0127] 100: Battery charging device

[0128] 110: Interface section

[0129] 120: Charging section

[0130] 130: Discharge section

[0131] 140: Control Unit

[0132] 150: Data processing unit

[0133] 151: Data generation unit

[0134] 153: Estimation

[0135] 155: Output section

[0136] 160: Detection unit

Claims

1. A method of charging a battery by dividing the charging section into multiple charging sections, A first discharge step of applying a first discharge pulse between the n-1th (n is a natural number greater than or equal to 2)th charge section and the nth charge section; and A second discharge step is included for applying a second discharge pulse between the nth charging section and the n+1th charging section, A battery charging method characterized in that the discharge rate of the second discharge pulse is configured to be less than the discharge rate of the first discharge pulse.

2. In paragraph 1, A battery charging method characterized in that the time for which the second discharge pulse is applied is configured to be longer than the time for which the first discharge pulse is applied.

3. In paragraph 2, A battery charging method characterized in that the discharge rate of the first or second discharge pulse and the time for which the first or second discharge pulse is applied are set so that the discharge amount of the second discharge step is less than or equal to the discharge amount of the first discharge step.

4. In paragraph 1, A battery charging method characterized in that the charging rate of the nth charging section is configured to be lower than the charging rate of the n-1th charging section.

5. In paragraph 1, A battery charging method characterized in that the charging environment of the plurality of charging sections is configured to be variably determined by an SOC value estimated based on a change in the characteristic data of the battery according to charging.

6. In paragraph 5, A battery charging method characterized in that the charging environment is at least one of the length of each section of the plurality of charging sections and the charging rate of each section of the plurality of charging sections.

7. A charging unit configured to charge a battery; A discharge unit configured to discharge the battery; and A control unit configured to control the charging unit so that the battery is charged in a plurality of charging sections, and to control the discharging unit so that a first discharge pulse is applied between the n-1 (n is a natural number greater than or equal to 2)-th charging section and the n-th charging section, and a second discharge pulse is applied between the n-th charging section and the n+1-th charging section, A battery charging device characterized in that the control unit is configured to control the discharge unit so that the discharge rate of the second discharge pulse is less than the discharge rate of the first discharge pulse.

8. In paragraph 7, A battery charging device characterized in that the control unit is configured to control the discharge unit so that the time for which the second discharge pulse is applied is longer than the time for which the first discharge pulse is applied.

9. In paragraph 8, A battery charging device characterized in that the control unit is configured to control the discharge rate of the first or second discharge pulse and the time for which the first or second discharge pulse is applied so that the discharge amount of the second discharge pulse is less than or equal to the discharge amount of the first discharge pulse.

10. In paragraph 7, The above control unit is configured to control the charging unit so that the charging environment of the plurality of charging sections is variably set using a preset target SOC, A battery charging device characterized in that the target SOC is estimated as the SOC value at which lithium is precipitated based on changes in the characteristic data of the battery according to charging.

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