Battery recovery method

Abstract

The present invention relates to a battery recovery method, and provides a battery recovery method for recovering a battery group, which has poor charging and discharging, by using a battery recovery device. The battery recovery method comprises: a first step of trickling charging by supplying a low current to a battery group in a completely discharged state until the battery group reaches a set voltage; a second step of restoring and charging, by supplying, to the battery group that has completed the first step, a constant current with a duty ratio having pulses generated in a cycle of energy charging, stopping, and energy discharging, until a set voltage is reached, thereby melting sulfate adhering to a battery electrode plate; a third step of restoring and charging, by supplying, to the battery group that has completed the second step, a constant voltage with a duty ratio having pulses generated in a cycle of energy charging, stopping, and energy discharging, until a set current is reached, thereby melting sulfate adhering to the battery electrode plate; and a fourth step of compensating for some self-discharged batteries among all the batteries constituting the battery group that has completed the recovery, by performing floating charging so as to maintain a fully charged state.

Description

Battery Restoration Method

[0001] The present invention relates to a battery restoration method, and more specifically, to a battery restoration method that restores the performance of a degraded battery so that the battery can be used up to its design life.

[0002]

[0003] Generally, a secondary battery refers to a battery that converts chemical energy into electrical energy to supply power to an external circuit, and upon discharge, receives external power to convert electrical energy back into chemical energy to store electricity.

[0004] Taking a lead-acid battery, or lead battery (hereinafter referred to as "battery") as an example, the battery generates electricity through a chemical reaction between an electrode plate containing a positive plate made of lead peroxide and a negative plate made of lead, and an electrolyte made of dilute sulfuric acid, and when charged after discharge, the battery's function is restored.

[0005] In addition, the battery is designed to maximize the contact area between the plates and the electrolyte by connecting several thin plates in parallel and arranging the positive and negative plates to face each other. During discharge, sulfuric acid is consumed, generating sulfates and water, and the sulfates adhere to the positive and negative plates, while the density of the electrolyte decreases due to the generated water.

[0006] However, when batteries undergo repeated charging and discharging over a long period, a phenomenon called sulfation occurs in which sulfates attached to the electrode plates do not detach during charging and remain intact.

[0007] This sulfation phenomenon blocks the electrical reaction pathway of the electrode plate, thereby acting as an insulating function. Consequently, the voltage, capacity, and specific gravity of the battery decrease, causing charging and discharging failures, which ultimately shortens the battery's lifespan and leads to its disposal.

[0008] Although there are many difficulties in disposing of such discarded waste batteries, there is an urgent need for research and development that can fundamentally improve the efficiency of recycling and restoration by restoring waste batteries as much as possible, rather than just disposing of them.

[0009]

[0010] Accordingly, the present invention has been devised to solve the problems of the prior art as described above, and aims to provide a battery restoration method that restores the performance of a battery and enables its use up to its design life by removing sulfates adhered to the electrode plates of a battery, by controlling the pulse width and supplying it to a battery whose performance has deteriorated due to poor charging and discharging, namely a lead-acid battery.

[0011]

[0012] A battery restoration method according to the present invention for achieving the above-mentioned purpose is a battery restoration method for restoring a battery group with poor charging and discharging using a battery restoration device, comprising: a first step of trickling charging by supplying a low current to a battery group in a completely discharged state until it reaches a set voltage; a second step of restoring and charging by melting sulfates attached to the battery electrode plates by supplying a constant current with a duty cycle having pulses generated in a cycle of energy charging, stopping, and energy discharging to the battery group that has completed the first step until it reaches a set voltage; a third step of restoring and charging by melting sulfates attached to the battery electrode plates by supplying a constant voltage with a duty cycle having pulses generated in a cycle of energy charging, stopping, and energy discharging to the battery group that has completed the second step until it reaches a set restoration termination current; and a fourth step of compensating to maintain a fully charged state by performing floating charging on some of the self-discharged batteries among the total batteries constituting the battery group that has completed restoration.

[0013] In addition, for the first stage operation in the battery restorer according to the present invention, the user can set the current within the range of 1A to 10A and the voltage within the range of 42V to 50V. The set current (Trickl_A) in the first stage can be set to a low current of about 2 to 3% relative to the total current capacity of the battery group, and the set cutoff voltage (Trickl_V) can be set to a voltage value of 48V to 49V, which is a state where the battery group is judged to be ready for restoration. To summarize the first stage, the trickling charge supplying low current in the first stage is a restoration preparation stage aimed at allowing the battery group to be sufficiently recovered to a level corresponding to 20 to 30% of its total capacity before the full-scale restoration stage. Through this stage, battery damage can be prevented and the restoration effect can be enhanced.

[0014] In addition, in the second stage, the user can set the set current value (CcCURR) within the range of 5 to 50 A in the constant current restoration stage section, and the constant current value supplied to the battery group is set within the range of 5 to 10% of the total battery capacity. This is because, based on the results of internal tests accumulated over time, when performing restoration work using this battery restorer, the highest restoration effect was observed in the 5 to 10% range of the constant current setting value. Typically, the higher the value set, the shorter the restoration time becomes, and the lower the setting value becomes, the longer the restoration time becomes. It was also observed that the restoration effect decreases as it deviates from the aforementioned constant current setting value.

[0015] In addition, in the third stage, the constant voltage value and the restoration termination current value can be set as a constant voltage restoration stage section. The constant voltage value (CgVOLT) can be set within the range of 46V to 60V, and the restoration termination current value (CvCURR) can be set within the range of 1A to 10A.

[0016] In addition, the setting of the constant voltage value supplied to the battery group is set to a maximum value within the range of the maximum allowable charging voltage value (CgVOLT) according to the battery manufacturer, and in the case of a 48V battery group, the manufacturer's maximum allowable charging voltage value is typically set within the range of 58V to 59V.

[0017] In this constant voltage restoration stage, the voltage of the battery group does not exceed the set constant voltage value, and the restoration work of the battery group is completed within that range while maintaining the set constant voltage value at a constant level, thereby preventing battery damage caused by overcharging at the same time as the restoration.

[0018] And the current value supplied to the battery group gradually decreases until the restoration cutoff current value reaches the set value as the battery group's state recovers from the set constant voltage and the charging state progresses. The restoration cutoff current value is typically recommended to be set to 1A to 3A for AGM batteries and 3A to 5A for flooded batteries applied to electric forklifts, etc.

[0019] Meanwhile, the fourth stage is a floating charging stage, and the floating charging can be set within the range of 46V to 60V with a voltage value close to the battery's charge absorption voltage. Typically, manufacturers publish a recommended floating voltage in the specifications of the battery group, and by referring to this, 54V to 55V is applied for a typical 48V battery group. This stage is a restoration finishing stage based on the floating setting voltage value, using a current less than or equal to the cutoff current value (CvCURR) set in the work section of the third stage mentioned above, so that all cells of the battery group can be fully charged. When the current value displayed on the battery restorer's display panel stably shows "0A," this stage ends, and the total restoration work of the present invention is completed.

[0020]

[0021] According to the battery restoration method of the present invention, by controlling the width of the pulse and supplying it to a battery whose performance has deteriorated due to poor charging and discharging, crystallized sulfates attached to the electrode plates inside the battery are removed and dissolved into the electrolyte, thereby restoring the performance of the battery and enabling the battery to be used until its design life.

[0022]

[0023] FIG. 1 is a perspective view of a battery restorer according to the present invention.

[0024] FIG. 2 is a front view of a battery restorer according to the present invention.

[0025] FIG. 3 is a rear view of a battery restorer according to the present invention.

[0026] FIG. 4 is a drawing illustrating a cable provided in a battery restorer according to the present invention.

[0027] FIG. 5 is a configuration diagram of a restoration system for restoring a battery using a battery restorer according to the present invention.

[0028] Figure 6 is a graph showing the restoration and charging status of a battery by the battery restoration method according to the present invention.

[0029] Figure 7 is a graph showing the pulses of a pulse width modulator configured in the battery restoration method according to the present invention.

[0030] FIG. 8 is a block diagram illustrating the configuration of a power generation unit according to the present invention.

[0031] FIG. 9 is a graph showing the output current and output voltage generated during one cycle in the power generation unit according to the present invention.

[0032]

[0033] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings.

[0034] The terms used in this invention are defined considering their functions within the invention; however, since these may vary depending on the intentions or practices of the user or operator, the definitions of these terms should be interpreted in a meaning and concept consistent with the technical details of this invention.

[0035] In addition, the embodiments of the present invention are not intended to limit the scope of the rights of the present invention, but are merely exemplary details of the components presented in the claims of the present invention, and are embodiments that include components that are included in the technical concept throughout the specification of the present invention and can be substituted as equivalents for the components of the claims.

[0036] Additionally, optional terms in the following examples are used to distinguish one component from another, and the components are not limited by said terms.

[0037] Accordingly, in describing the present invention, detailed descriptions of related prior art that may unnecessarily obscure the essence of the invention are omitted.

[0038]

[0039] The attached drawings, FIGS. 1 to 9, are drawings illustrating a battery restorer according to the present invention and a battery restorer method using the same.

[0040] In the present invention, batteries such as golf cart batteries, BTS backup batteries, electric forklift batteries, and industrial UPS batteries are selected as batteries to be restored, but are not limited thereto.

[0041] Most of these batteries are equipped with a 48V battery group capable of charging and discharging, and typically, a 48V battery group is equipped with four 12V batteries (lead-acid batteries) connected in series or 24 2V batteries connected in series.

[0042] In addition, the 12V battery is equipped with 6 blocks of 2V lead (Pb) plates connected in series with a separator in between.

[0043] Hereinafter, the present invention describes, as an example, the restoration of a 48V battery group composed of four 12V batteries connected in series using a battery restorer.

[0044] As shown in FIGS. 1 to 4, the battery restorer (100) according to the present invention is equipped with a microcomputer (180), a display panel (110) on the front, and a plurality of connection terminals on the rear.

[0045] A microcontroller unit (Micro Controller Unit: MCU) (180) is a control unit that generally controls the battery restorer (100) and is equipped to control the energy charging (transfer), stopping, and energy discharging of the battery group (BG) according to the charging or restoration state of the battery group (BG).

[0046] The battery restorer (100) by such a microcomputer (180) charges and discharges the battery group (BG) by the control operation of the microcomputer (180) and also provides a pulse wave for removing sulfates attached to the electrode plates of the battery configured therein.

[0047] And, as shown in FIGS. 2 and 3, a plurality of heat dissipation holes (160) (161) are formed on the front and rear surfaces of the battery restorer (100) to dissipate heat from the restorer (100) by means of a heat dissipation fan (not shown).

[0048] In addition, the display panel (110) on the front of the battery restorer (100) is connected to the microcomputer (180) as in FIG. 2 to display information and the current status regarding the sequence of the charging and discharging cycles of the battery group (BG).

[0049] The connection terminals on the rear of the battery restorer (100) include a power connection terminal (120) to which external power is connected and supplied as in FIG. 3, a battery connection terminal (140) connected to the battery group (BG) via a cable (170), and an option connection terminal (150) that can provide various options to the battery restorer (100).

[0050] Additionally, a power switch (130) for turning the battery restorer on / off may be further provided on the rear of the battery restorer (100).

[0051] And, the battery connection terminal (140) of the battery restorer (100) is provided to be connected to the battery group (BG) by a cable (170). As shown in FIG. 4, the cable (170) has a connection connector (171) formed at one end that is inserted into and connected to the battery connection terminal (140) of the battery restorer (100), and a clamp connector (172) provided at the other end that is connected to the positive terminal of the battery group (BG).

[0052] These clamp connectors (172) are equipped with a temperature sensor (173) that detects the terminal temperature of the battery group (BG). The temperature generated at the positive terminal of the battery group (BG) is detected by the temperature sensor (173), thereby enabling the recognition of temperature data of the battery group (BG).

[0053] Meanwhile, the microcomputer (180) adjusts the duty ratio of the pulse output to the battery group (BG) according to the terminal temperature of the battery group (BG) detected by the temperature sensor (173).

[0054] In particular, the microcomputer (180) collects the temperature generated at the positive terminal of the battery group (BG) to be restored and recognizes it as temperature data. During the restoration process, according to a pre-program, the temperature value detected in the battery group (BG) is based on the optimal temperature for battery operation, 25°C. Whenever the temperature increases by 1°C, a voltage compensation value is applied to adjust the output voltage value output to the battery group (BG), thereby preventing battery damage.

[0055] At this time, it is preferable to set the voltage compensation per 1°C of temperature to -70 to -120 mv / °C. For example, when the voltage compensation per 1°C is set to -70 mv / °C, if the temperature of the battery group (BG) rises by 1°C from 25°C to 26°C while operating with an output voltage of 50V, the output voltage is adjusted to 49.93V, which is lowered by -70 mv (-0.07 v). When the voltage compensation per 1°C is set to -120 mv / °C and the same as the aforementioned operating conditions are met, the output voltage is adjusted to 49.88V, which is lowered by -120 mv (-0.12 v), thereby preventing damage to the battery caused by the temperature rise.

[0056] In addition, the microcomputer (180) generates an artificial pulse (a pulse generated through a combination of energy charging, stopping, and energy discharging times) to increase the efficiency of sulfate removal, thereby enabling a duty ratio optimized for removing sulfates attached to the electrode plate compared to a general simple pulse (a pulse generated through a combination of energy charging and stopping times) method without a discharge function.

[0057] The microcomputer (180) described above checks the voltage of the 48V battery group (BG) of the restoration target, which is composed of four 12V batteries connected in series. As shown in Table 1 below, if the voltage of the battery group (BG) is less than 45.24V (11.31V × 4 batteries), which is 10% of the total capacity, the battery group (BG) is charged with a low current to a maximum of 47V. At this time, when the voltage of the battery group (BG) is less than 45.24V and there is a remaining charge, the battery group (BG) is completely discharged until the voltage reaches 42V, and then charging with a low current can further increase the charging efficiency.

[0058]

[0059] < Lead-acid Battery Charge Status (Based on Stand-By Status) > Charge Status 12V Battery (V) Voltage per Cell (2V) 100% 12.7 or more 2.12 or more 90% 12.5 2.08 80% 12.4 2.07 70% 12.3 2.05 60% 12.2 2.03 50% 12.06 2.01 40% 11.9 1.98 30% 11.75 1.96 20% 11.58 1.93 10% 11.31 1.89 10.5 1.75

[0060] That is, the initial operating voltage for removing sulfates attached to the battery electrode plates is set to 42V, and a low current (low current, hereinafter referred to as "low current") charging current is provided in a state adjusted to a maximum of 47V to begin the full restoration of the battery group (BG).

[0061] For example, if a strong pulse is provided to restore the battery group (BG) while the battery group (BG) is below 47V, the sulfate is not effectively removed because the strong pulse is provided while charging is not properly performed, and not only is damage to the battery electrode plates caused, but the restoration is not performed smoothly, resulting in almost no restoration effect.

[0062] Meanwhile, the battery restorer (100), which is a system controller, is equipped with a power generation unit (200) and a 48V battery group (BG) to be restored connected, as shown in FIG. 5.

[0063] In particular, the battery restorer (100) is configured to apply the current and voltage generated by the power generation unit (200) and supplied to the battery group (BG) to each restoration stage as a duty ratio programmed for optimization, thereby enabling the effective removal of sulfates attached to the battery electrode plates.

[0064] Each of these battery restorers (100) and power generation units (200) is equipped with a microcomputer, and through a protocol communication function between the two microcomputers, output values ​​of current and voltage controlled according to the duty ratio set for each restoration stage are output to the battery group (BG) to be restored.

[0065] The duty ratio is applied to each restoration step in the restoration method described below, but is configured to be applied at 100% in the first step (trickling filling step) and the fourth step (floating filling step).

[0066] Furthermore, the application of the duty ratio in the second stage (CC stage) and third stage (CV stage), which are the full-scale restoration phases, is configured to apply the optimal lead-acid battery restoration duty ratio by comprehensively determining it based on the operating temperature perceived from the battery group (BG), the predicted value of internal resistance through the instantaneous voltage change of the battery group (BG) during the restoration process, and internally accumulated restoration data.

[0067] For example, during the restoration process, if the rate of increase in battery voltage and temperature is rapid considering the set current value, the duty ratio is adjusted to a lower level; in normal conditions where such phenomena do not occur, the optimal duty ratio set according to a standard formula is applied.

[0068] Among the duty ratios applied in the restoration phase (i.e., the second and third phases), the output value generated by a simple pulse (Natural Pulse) created through a combination of energy charging and stopping times is received from the power generation unit (200), and in addition to this, the overall standard duty ratio is set by including the output value generated by an artificial pulse that combines the discharge time using the discharge function of the battery restorer (100) by the microcomputer (180).

[0069] Accordingly, the standard duty ratio applied to the final restoration is generated by combining the energy charging time, the pause time, and the energy discharge time in units of ms (1 / 1000 second). Here, the standard duty ratio to be applied to the restoration step is determined by combining the energy charging (transfer) time of 1 to 1000 ms, the pause time of 1 to 100 ms (1 to 100 ms), and the energy discharge time of 1 to 100 ms.

[0070] The duty cycle described above is controlled by a Pulse Width Modulation (PWM). This PWM circuit generates a continuous sequence of pulses, and each pulse starts at a constant interval as shown in Fig. 7 and continues for a programmed time.

[0071] Each new pulse starts at a constant interval, but the pulse length (or width) of each interval can be changed. That is, as shown in FIG. 7, the information conveyed by the signal is determined by the ratio (or "duty-rate") of the high time and low time of the signal in a given "pulse window."

[0072] These digital signals pass through a simple low-pass filter that integrates the digital waveforms to generate an analog voltage proportional to the average pulse width over a fixed interval (the interval is determined by the RC time constant and the pulse frequency).

[0073] The power generation unit (200) of the present invention basically generates pulses in the manner described above, and the battery restorer (100) is configured to determine the pulse length (or width) and duty ratio of each interval that are optimal for melting and reducing sulfates attached to the electrode plate, so that an optimal artificial pulse is output to the battery group (BG). That is, in order to generate sufficient pulses optimized for restoration, the present invention provides a discharge function to expand the pulse depth, that is, the range of vertical conversion, thereby improving the removal efficiency of sulfates attached to the electrode plate.

[0074] The depth of the pulse according to the present invention has a range of vertical transformation consisting of section a, which is a "+" section where energy is charged in FIG. 7, section b, which is a "0" section where it is stopped, and section c, which is a "-" section where energy is discharged.

[0075] Therefore, the artificial pulse generated in the present invention has an upper and lower amplitude more than twice as large as a simple pulse, so that sulfates attached to the battery electrode plate can be effectively removed.

[0076]

[0077] Meanwhile, the power generation unit (200) of the present invention is a slim device of 1U size and is composed of a power module designed to be highly efficient, providing a single output of 3200W as AC / DC power and supporting a high output density of 37W / inch.

[0078] This power generation unit (200) is a power supply with PWM switching technology having a pre-loaded programmable regeneration / charge curve suitable for removing sulfates generated from the internal electrode plates of three different types of lead batteries (see FIG. 8).

[0079] In addition, using the output programming function, the output current and voltage can be adjusted to change dynamically in one cycle from 0 to 5V as shown in Figure 9 through the built-in potentiometer or PMBus Protocol.

[0080] In particular, the pulse wave flows dynamically due to the dynamic change in the output current, and a trim function is provided to this dynamic output current.

[0081] In other words, the function of adjusting the output voltage using a dynamic current trimming function enables the efficient removal of sulfates attached to the electrode plates inside the battery through micro-vibrations generated during the process of balancing the large oscillations of dynamic pulses.

[0082] In addition, the output current exhibits a dynamic rising curve between 9 and 100%, and the output voltage exhibits a dynamic rising curve between 36 and 60V. As these output currents and output voltages move in a mixed manner, sulfates attached to the electrode plates inside the battery can be removed more effectively.

[0083] The output value generated by such power generation unit (200) is transmitted as a digital signal through protocol communication with the battery restorer (100) using the microcontroller (MCU) of the power generation unit (200), and the battery restorer (100) generates a standard artificial pulse used for restoration by combining the energy charging (transfer) time (1-1000ms), stop time (1-100ms), and discharge time (1-100ms) per pulse period with added discharge function, and outputs it to the battery group (BG).

[0084] The power generation unit (200) is separately modularized and connected to the power connection terminal of the battery restorer (100) to transmit various data and output values ​​to the battery restorer (100).

[0085]

[0086] Meanwhile, the battery restoration method according to the present invention is configured to restore a battery group (BG) with poor charging and discharging using a battery restoration device (100).

[0087] This battery restoration method consists of a total of four steps, as illustrated in Fig. 6.

[0088] That is, the first step is to trickle charging by supplying a low current to a completely discharged battery group (BG) until it reaches a set voltage.

[0089] The second step is to restore and charge the battery group (BG) by supplying a constant current with a duty cycle having pulses generated in a cycle of energy charging, stopping, and energy discharging as shown in FIG. 6 until it reaches a set voltage, thereby melting the sulfates attached to the battery electrode plates.

[0090] The third step is to restore and charge the battery group (BG) that has completed the second step by supplying a constant voltage with a duty cycle having pulses generated in a cycle of energy charging, stopping, and energy discharging until it reaches a set voltage, thereby melting the sulfates attached to the battery electrode plates.

[0091] Step 4 is a step of compensating for self-discharged batteries among the total batteries constituting the restored battery group (BG) by performing floating charging to maintain a fully balanced charge state.

[0092] Specifically, the first step (trickling charging step) is a step of charging a completely discharged battery group (BG) by supplying a low current. Since supplying a high initial current while the battery is completely discharged can increase the burden on the batteries constituting the battery group (BG) and cause damage to them, this is a restoration preparation step in which a low current is supplied to charge the battery in order to prevent this and increase restoration efficiency.

[0093] Through this first step, a low current set within the range of 1 to 10 A and 42 V to 50 V is supplied so that the battery group (BG) can recover its function from the initial stage of complete discharge to a certain level, thereby allowing it to be charged to 20 to 30 percent of the total capacity of the battery group (BG).

[0094] In addition, since the battery group (BG) to be restored consists of four 12V batteries connected in series, the voltage at which charging takes place in the first stage from 42V, when the battery group (BG) is completely discharged, can be set up to 50V, including 47V, which corresponds to a maximum of 30% of the total capacity of the battery group (BG). Here, if the set voltage exceeds 50V, charging takes a long time due to low current charging, resulting in reduced charging efficiency, and the voltage range for the restoration operation becomes narrower, thereby reducing the restoration effect.

[0095] Thus, the voltage according to the total capacity of the 48V battery group (BG) to be restored is checked, and if the voltage of the battery group (BG) is less than 45.24V, which is 10% of the total capacity, the battery group (BG) is completely discharged and then a low current is supplied to charge it up to a maximum of 50V.

[0096] That is, the initial operating voltage for removing sulfates attached to the battery electrode plates is set to 42V, and a low current, i.e., a low current charging current, is provided to the battery group (BG) while the voltage is adjusted to a maximum of 47V to 48V, thereby completing preparations to begin full-scale battery restoration.

[0097] At this time, depending on the total capacity of the battery group (BG) to be restored, the user can set the set current value and the final voltage targeted in the first step through the display panel (110) of the battery restorer (100).

[0098] In particular, the first stage is a restoration preparation stage, and the output current value with a 100% duty ratio is supplied to the battery group (BG) to charge it until it reaches the set final voltage, and when the charge state of the battery group (BG) reaches the set final voltage value, it automatically moves to the next second stage and restoration begins.

[0099] Meanwhile, the second stage (CC stage) is a stage in which restoration is initiated by supplying a constant current to the battery group (BG) with poor charging and discharging until the set voltage is reached.

[0100] In particular, in the second step of this battery restorer, the user is enabled to set a constant current value within the range of 5 to 50 A.

[0101] And, as shown in Stage 2 in FIG. 6, the constant current supplied to the battery group (BG) starts from a set current value and continues to supply a constant current value (CcCURR) until the voltage of the battery group (BG) reaches a set voltage to proceed with restoration.

[0102] In this way, if a constant current is continuously supplied at a constant current value until the voltage of the battery group (BG) reaches the set voltage, the voltage at the set voltage (CgVolt) can be filled more densely.

[0103] From this second stage, full-scale battery restoration and charging functions are performed simultaneously, and a constant current controlled by the microcomputer (180) of the battery restorer (100) is output to the battery group (BG) to melt the sulfates attached to the battery electrode plates and restore them to their original chemical / physical state.

[0104] At this time, if the set constant current value is set to less than 5% of the total battery capacity, the charging efficiency decreases as it is set lower, and the restoration effect is reduced due to low power. If it is set to more than 10% of the total battery capacity, the charging function is prioritized over restoration as it is set higher, and the restoration space becomes relatively narrower, resulting in a decrease in restoration efficiency. Thus, the pulse frequency of the constant current output to the battery group (BG) for restoration is optimized within the range of 5 to 10% of the total battery capacity, and the restoration effect can be enhanced by the optimized pulse.

[0105] In addition, the set voltage (CgVolt) at this stage is not set to exceed the maximum charging voltage value typically announced by the battery manufacturer to prevent battery damage caused by overvoltage. At this time, for the 48V battery group (BG), the set maximum charging voltage is preferably 58 to 59V, and it is desirable not to set it to exceed 60V.

[0106] When the restoration status of the battery group (BG) reaches the set final voltage value (CgVOLT), the second stage ends and automatically proceeds to the third stage, and restoration by the third stage begins.

[0107] Meanwhile, the third stage (CV stage) is a restoration stage using a constant voltage, and the set voltage of the constant voltage is 46V to 60V.

[0108] And, in the third stage of restoration, restoration is carried out until the current value provided to the battery group (BG) through the battery restorer (100) reaches the restoration termination setting current value (CvCURR), as shown in Stage 3 of FIG. 6, within a range where the maximum voltage of the battery group (BG) does not exceed the set constant voltage value during restoration and charging operations, and the charging function is also performed simultaneously with the restoration operation.

[0109] In particular, by supplying current while gradually lowering the set current value even when the voltage of the battery group (BG) reaches the set voltage (CgVolt), it is possible to fill the voltage more densely even at the same set voltage.

[0110] And, as described above, the gradually decreasing current value is operated until it reaches the set restoration termination current value, and when the current value reaches the set restoration termination current value, the third step is terminated. At this time, the restoration termination current value can be set to 1 to 10 A.

[0111] In this third step, just like the aforementioned second step, a constant voltage controlled by an optimal duty ratio through the microcomputer (180) of the battery restorer (100) is output to the battery group (BG) to melt the sulfate attached to the battery electrode plate and restore it to its original chemical / physical state.

[0112] And, since the setting voltage in the third stage is applied in the same way as in the second stage, the significance of the threshold value for the setting voltage is replaced by the explanation of the second stage.

[0113] When the battery group (BG) is fully charged through the restoration process in this third stage, the third stage ends and the fourth stage proceeds automatically.

[0114] Meanwhile, the fourth stage (floating charging stage) is a restoration recovery stage that ensures all cells forming the battery group are charged evenly.

[0115] In particular, the floating charge in the fourth stage fully charges some of the batteries that have been self-discharged in the battery group (BG) with a voltage of 46V to 60V.

[0116] Specifically, floating charging is performed at a voltage of 53V to 56V, and floating charging is performed at a voltage value lower than the maximum charging voltage (CgVOLT).

[0117] Typically, for AGM or Gel batteries, floating charging is performed by applying the voltage announced by the manufacturer, and the FvVOLT value is set in the battery restorer (100) according to the manufacturer's announced standards.

[0118] In the case of a flooded battery, if there is no manufacturer-published FvVOLT, a voltage value typically set about 3 to 4V lower than the maximum charging voltage (CgVOLT) is set so that the entire battery can be fully charged evenly.

[0119]

[0120] Although the present invention has been described in detail through specific embodiments, this is for the purpose of specifically explaining the invention, and the invention is not limited thereto. It is evident that modifications or improvements can be made by those skilled in the art within the technical scope of the invention.

[0121] All simple variations or modifications of the present invention fall within the scope of the present invention, and the specific scope of protection of the present invention will be clarified by the appended claims.

Claims

1. A battery restoration method for restoring a battery group with poor charging and discharging using a battery restorer, wherein A first step of trickling charging by supplying a low current to a battery group in a completely discharged state until it reaches a set voltage; A second step of restoring and charging by supplying a constant current with a duty cycle having pulses generated in a cycle of energy charging, stopping, and energy discharging to a battery group that has completed the first step until a set voltage is reached, thereby melting the sulfates attached to the battery electrode plates; A third step of restoring and charging by supplying a constant voltage with a duty cycle having pulses generated in a cycle of energy charging, stopping, and energy discharging to the battery group that has completed the second step until it reaches a set current, thereby melting the sulfates attached to the battery electrode plates; A battery restoration method comprising: a fourth step of performing floating charging on some of the self-discharged batteries among the entire battery group constituting the restored battery group to compensate for maintaining a fully charged state.

2. In Claim 1, A battery restoration method in which, in the first stage, trickling charging is performed up to 20–30% of the total capacity of the battery group by supplying a low current set to 1–10A and 42V–50V.

3. In Claim 1, A battery restoration method in which the set constant current value range in the second stage is 5 to 50 A, and the constant current supplied to the battery group is restored using a customized artificial pulse based on a pulse width modulator using the same current value until the voltage of the battery group reaches a set constant voltage value.

4. In Claim 1, A battery restoration method in which the set constant voltage value range in the third stage is 46V to 60V, and the constant voltage supplied to the battery group is restored using a customized artificial pulse based on a pulse width modulator from a state where the set voltage is set to the maximum value, until the output current value of the battery restorer reaches the set cutoff current value within the range of the set cutoff current value from below the set current value.

5. In Claim 1, A battery restoration method in which floating charging in the fourth stage is performed in a voltage range of 46V to 60V, and self-discharge of some cells generated during restoration is supplemented and charged from below a set cutoff current value until the output current of the battery restorer stably reaches "0A" in a battery absorption voltage range section 3 to 4V lower than the set constant voltage, so that all batteries in the battery group can reach a fully charged state.

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