Quick charging method and system, energy storage equipment, control circuit of energy storage equipment and medium

Abstract

The invention relates to the technical field of energy storage equipment, in particular to a quick charging method and system, energy storage equipment, a control circuit of the energy storage equipment and a medium. The quick charging method comprises the following steps of: charging the energy storage equipment by using maximum charging power supported by the energy storage equipment to obtain lithium protection impedance of a lithium protection MOS (Metal Oxide Semiconductor) tube; the charging cut-off voltage of the power management chip is set to be preset cut-off voltage, and the preset cut-off voltage is higher than the charging limiting voltage of the lithium battery protection chip; performing constant-current charging on the energy storage equipment until the lithium battery protection chip is triggered to execute overvoltage protection, and obtaining the maximum voltage value of the energy storage battery in the constant-current charging process; acquiring a voltage sampling error of the power management chip based on the charging limiting voltage and the maximum voltage value; and real-time charging current of the energy storage equipment is collected, a voltage correction value is obtained based on the real-time charging current and the lithium protection impedance, and real-time cut-off voltage of the energy storage equipment is obtained according to the voltage correction value and the voltage sampling error. The charging efficiency can be effectively improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of energy storage devices, in particular to a fast charging method, system, energy storage device and control circuit thereof, and medium. BACKGROUND

[0002] In recent years, with the popularity of portable energy storage devices and the rapid development of fast charging technology, users' demand for charging speed of energy storage devices is increasing. Charging speed is one of the key factors affecting user experience, and the setting of charging cutoff voltage directly determines the charging efficiency and final capacity of the battery. If the cutoff voltage is set too low, the battery cannot be fully charged to a higher capacity, and during the constant voltage charging phase, the charging current will gradually decrease as the voltage approaches the cutoff value, resulting in slower overall charging speed.

[0003] Currently, the charging design of energy storage devices usually adopts a conservative charging cutoff voltage strategy for safety and cost considerations, which reduces the charging cutoff voltage and limits the charging speed. SUMMARY

[0004] The embodiments of the present application provide a fast charging method, system, energy storage device and control circuit thereof, and medium to solve the problem of low charging efficiency of energy storage devices.

[0005] The present application discloses a fast charging method applied to an energy storage device, wherein the energy storage device comprises an energy storage battery, a power management chip, a lithium battery protection chip and a charging circuit connected with the energy storage battery respectively, the charging circuit comprises a current detection resistor and a lithium protection MOS tube connected in series, and the lithium battery protection chip is connected with the lithium protection MOS tube. The fast charging method comprises the following steps: charging the energy storage device using the maximum charging power supported by the energy storage device to obtain the lithium protection impedance of the lithium protection MOS tube; setting the charging cutoff voltage of the power management chip as a preset cutoff voltage, wherein the preset cutoff voltage is higher than the charging limit voltage of the lithium battery protection chip; performing constant current charging on the energy storage device until triggering the lithium battery protection chip to execute overvoltage protection, and obtaining the highest voltage value of the energy storage battery during the constant current charging process; obtaining the voltage sampling error of the power management chip based on the charging limit voltage and the highest voltage value; collecting the real-time charging current of the energy storage device, obtaining the voltage correction value based on the real-time charging current and the lithium protection impedance, and obtaining the real-time cutoff voltage of the energy storage device according to the voltage correction value and the voltage sampling error.

[0006] Optionally, the step of obtaining the real-time cutoff voltage of the energy storage device according to the voltage correction value and the voltage sampling error comprises: obtaining the maximum charging voltage of the energy storage battery, and obtaining the real-time cutoff voltage according to the maximum charging voltage, the voltage correction value and the voltage sampling error.

[0007] Optionally, the step of obtaining the real-time cutoff voltage according to the maximum charging voltage, the voltage correction value and the voltage sampling error comprises: subtracting a preset tolerance value from the sum of the maximum charging voltage, the voltage correction value and the voltage sampling error to obtain the real-time cutoff voltage.

[0008] Optionally, the step of setting the preset cutoff voltage of the power management chip comprises: obtaining a chip sampling error of the power management chip and a charging limit voltage of the lithium protection chip, and obtaining the preset cutoff voltage by adding the chip sampling error and the charging limit voltage.

[0009] Optionally, after the step of charging the energy storage device using the maximum charging power supported by the energy storage device, the method further comprises: measuring a voltage difference between a negative electrode of the energy storage battery and a ground wire; measuring a voltage drop on both sides of the current detection resistor, and obtaining a current according to the voltage drop and a resistance value of the current detection resistor; obtaining the lithium protection impedance according to the voltage difference and the current.

[0010] Optionally, the step of obtaining the voltage sampling error of the power management chip based on the charging limit voltage and the maximum voltage value comprises: obtaining the voltage sampling error by subtracting the charging limit voltage from the maximum voltage value.

[0011] The application further discloses a fast charging system applied to an energy storage device, and the fast charging method comprises the following modules: a charging module, which is configured to charge the energy storage device using the maximum charging power supported by the energy storage device, so as to obtain a lithium protection impedance of the lithium protection MOS tube; a boosting module, which is configured to boost a preset cutoff voltage of the power management chip, so that the preset cutoff voltage is higher than a charging limit voltage of the lithium protection chip; an overvoltage module, which is configured to perform constant current charging on the energy storage device until triggering the lithium protection chip to perform overvoltage protection, and obtain a maximum voltage value of the energy storage battery in the constant current charging process; an error module configured to obtain a voltage sampling error of the power management chip based on the preset cutoff voltage and the maximum voltage value; a real-time module configured to collect a real-time charging current of the energy storage device, obtain a voltage correction value based on the real-time charging current and the lithium protection impedance, and obtain a real-time cutoff voltage of the energy storage device according to the voltage correction value and the voltage sampling error.

[0012] The application further discloses a control circuit of an energy storage device, which comprises: an input-output interface configured to charge or discharge the energy storage device; a battery pack configured to store electric quantity; a lithium protection module connected to the battery pack and configured to protect the battery pack from overcharging; a battery management module connected to the input-output interface and the lithium protection module and configured to control the charging and discharging current and / or voltage of the battery pack and protect the battery pack from overcharging; a control chip connected to the battery management module and configured to execute the steps of the method; a display circuit connected to the control chip and configured to display the operation result of the control chip.

[0013] The application further discloses a computer readable storage medium storing a computer program, wherein the computer program is executed by a processor to make the processor execute the steps of the method.

[0014] The application further discloses an energy storage device comprising a memory and a processor, wherein the memory stores a computer program, and the computer program is executed by the processor to make the processor execute the steps of the method.

[0015] The fast charging method, system, energy storage device, control circuit and medium provided by the application have the following advantages: The lithium protection impedance of the lithium protection MOS tube is obtained, the charging cutoff voltage of the power management chip is set as a preset cutoff voltage higher than the charging limit voltage of the lithium protection chip, so that the maximum voltage value when the lithium protection chip is triggered can be obtained, the voltage sampling error of the power management chip is calculated based on the charging limit voltage of the lithium protection chip and the maximum voltage value, the voltage correction value is calculated based on the real-time charging current and the lithium protection impedance, and the cutoff voltage is updated in real time in combination with the voltage sampling error, so that the power management chip can accurately judge the actual voltage of the battery even if the charging current changes (for example, decreases from a large current to a small current), the "false cutoff" caused by the voltage drop of the lithium protection MOS tube or the voltage sampling error is avoided, the constant current charging time is prolonged, the proportion of the constant voltage stage is reduced, the total charging time is shortened, and the charging efficiency is improved. BRIEF DESCRIPTION OF DRAWINGS

[0016] The technical solutions of the present application will be further described in detail below with reference to the accompanying drawings and embodiments. Figure 1 is a flowchart of an embodiment of the fast charging method provided by the present application; Figure 2 is a structural schematic diagram of an embodiment of the energy storage device provided by the present application; Figure 3 is a structural schematic diagram of an embodiment of the fast charging system provided by the present application; Figure 4 is a circuit schematic diagram of an embodiment of the control circuit of the energy storage device provided by the present application; Figure 5 is a circuit schematic diagram of an embodiment of the power management chip provided by the present application; Figure 6 is a circuit schematic diagram of an embodiment of the lithium battery protection chip provided by the present application; Figure 7 is a circuit schematic diagram of an embodiment of the control chip provided by the present application; Figure 8 is a structural schematic diagram of another embodiment of the energy storage device provided by the present application; Figure 9 is a structural schematic diagram of an embodiment of the computer readable storage medium provided by the present application.

[0017] The reference signs in the drawings are as follows: 10, energy storage device; 11, energy storage battery; 12, charging loop; 121, current detection resistor; 122, lithium protection MOS tube; 13, power management chip; 14, lithium battery protection chip; 20, fast charging system; 21, charging module; 22, voltage boosting module; 23, overvoltage module; 24, error module; 25, real-time module; 30, control circuit of the energy storage device; 31, input and output interface; 32, battery pack; 33, lithium battery protection module; 34, battery management module; 35, control chip; 36, display circuit; 40, energy storage device; 41, processor; 42, memory; 50, computer readable storage medium; 51, computer program. DETAILED DESCRIPTION

[0018] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict. The preferred embodiments of the present application will be described in detail below with reference to the accompanying drawings.

[0019] Please refer to Figure 1 andFigure 2 Figure 1 is a flowchart of an embodiment of the fast charging method provided by the present application, Figure 2 is a structural schematic diagram of an embodiment of the energy storage device provided by the present application. The energy storage device 10 comprises an energy storage battery 11 and a charging circuit 12 connected to the energy storage battery 11. The charging circuit 12 comprises a current detection resistor 121 and a lithium protection MOS tube 122 connected in series in the charging circuit 12. The lithium protection MOS tube is connected between the negative electrode of the energy storage battery 11 and the system ground. When the lithium protection MOS tube 122 is in the off state, the charging circuit 12 is disconnected, and the energy storage battery 11 cannot be charged. When the lithium protection MOS tube 122 is in the on state, the charging circuit 12 is turned on, and the energy storage battery 11 can be charged.

[0020] The energy storage device 10 further comprises a power management chip 13 and a lithium protection chip 14 connected to the energy storage battery 11. One end of the lithium protection chip 14 is connected to the energy storage battery 11 to obtain the charging parameters of the energy storage battery, such as the current voltage of the energy storage battery 11. The lithium protection chip 14 controls the off or on of the lithium protection MOS tube 122 based on the charging parameters. For example, when the current voltage exceeds the charging limit voltage of the lithium protection chip 14, the lithium protection chip 14 drives the lithium protection MOS tube 122 to be off to avoid overcharging of the energy storage battery 11. The power management chip 13 is connected to the energy storage battery 11 through the lithium protection chip 14 to obtain the current voltage of the energy storage battery 11. When the current voltage exceeds the charging cutoff voltage, the power management chip 13 reduces the charging current or stops charging.

[0021] ​In one embodiment, the maximum charging voltage of the energy storage battery 11 of the energy storage device 10 is 4.2V, the overcharge protection voltage is 4.25V, the charging limit voltage of the lithium battery protection chip 14 is 4.225V±15mV, and the sampling error of the power management chip 13 is ±40mV. These data can be obtained in advance through the product data provided by the manufacturers of the energy storage battery 11, the lithium battery protection chip 14 and the power management chip 13. Since the operation of disconnecting the lithium protection MOS tube 122 after the lithium protection chip 14 triggers protection is irreversible, the power management chip 13 needs to ensure that the lithium protection chip 14 will not be triggered when designing the charging cutoff voltage. The charging limit voltage of the lithium protection chip 14 is 4.210V~4.240V, and the charging cutoff voltage needs to be lower than 4.210V. The charging limit voltage of the energy storage battery 11 is 4.2V, which is lower than 4.210V, so the minimum voltage can be set to 4.2V. Since the sampling error of the power management chip 3 is ±40mV, it is possible that the voltage value obtained by sampling is 4.2V, and the actual voltage value is 4.24V (4.2V+40mV). The final charging cutoff voltage of the power management chip 13 needs to be limited to 4.16V (4.2V-40mV). A lower charging cutoff voltage will make the constant current charging time end early, the large current charging time significantly reduce, the charging time be prolonged, and the charging efficiency be significantly reduced.

[0022] Therefore, it is necessary to provide a fast charging method which can effectively improve the charging efficiency without triggering the lithium protection chip.

[0023] The fast charging method provided by the application comprises the following steps: S101: charging the energy storage device using the maximum charging power supported by the energy storage device to obtain the lithium protection impedance of the lithium protection MOS tube.

[0024] In one specific implementation scenario, since the lithium protection MOS tube is connected in series in the charging circuit, when charging the energy storage battery, the lithium protection impedance of the lithium protection MOS tube itself will cause the lithium protection MOS tube to have a voltage division effect. The voltage division will directly distort the voltage sampling accuracy of the power management chip. Specifically, the voltage sampling point of the power management chip is usually between the positive electrode (BAT+) of the battery and the system ground (GND). Since the negative electrode (BAT-) of the battery is separated from the system ground (GND) by the lithium protection MOS tube, there is a voltage drop between the negative electrode (BAT-) of the battery and the system ground (GND) during charging. Therefore, when the power management chip collects the voltage, the actual voltage value obtained is the sum of the cell voltage of the energy storage battery and the voltage drop of the lithium protection MOS tube. There is a false high error caused by the voltage division of the lithium protection MOS tube. Therefore, the voltage division of the lithium protection MOS tube needs to be obtained, and the voltage division is subtracted when the battery voltage is actually calculated, so as to avoid stopping the constant current charging when the voltage of the energy storage battery actually does not reach the charging cutoff voltage, and to reduce the charging efficiency.

[0025] In the embodiment, the maximum charging power supported by the energy storage device is used to charge the energy storage device, a fast charging protocol supported by the energy storage device is obtained, and the energy storage device is charged at the maximum charging power (for example, 20V / 3A) corresponding to the fast charging protocol, so as to ensure that the entire energy storage device works at the maximum design current. The lithium protection MOS tube flows through the peak current, so that the voltage drop of the lithium protection MOS tube is significant, and the measurement accuracy can be effectively improved. The multimeter is adjusted to the direct current millivolt (mV) range, the red meter pen is connected to the negative electrode (B-) of the energy storage battery, the black meter pen is connected to the system ground (GND), and the reading is recorded. The reading is the voltage drop of the MOS tube .

[0026] The current is The voltage drop of the lithium protection resistance of the lithium protection MOS tube In order to obtain the voltage drop of the lithium protection resistance The current needs to be measured Since the current detection resistor and the lithium protection MOS tube are connected in series, the current can be obtained by detecting the current of the current detection resistor The current detection resistor is usually a 5mΩ~10mΩ chip resistor, and the voltage drop across the two ends of the current detection resistor is measured by a multimeter According to the nominal value of the current detection resistor The current can be calculated , Since the resistance value of the current detection resistor is small, the voltage division is also small, and the influence on the calculation of the battery voltage is small and can be ignored.

[0027] After the current is obtained The voltage drop The lithium protection resistance , .

[0028] S102: set the charging cutoff voltage of the power management chip to a preset cutoff voltage, so that the preset cutoff voltage is higher than the charging limit voltage of the lithium battery protection chip.

[0029] In a specific implementation scenario, the charging cutoff voltage of the power management chip is set to a preset cutoff voltage, so that the preset cutoff voltage is higher than the charging limit voltage of the lithium battery protection chip, and the charging limit voltage of the lithium battery protection chip can be reached, avoiding that the charging cutoff voltage is too low and the lithium battery protection cannot be triggered to be in a constant voltage charging state.

[0030] Specifically, if the preset cutoff voltage of the power management chip is less than or equal to the charging limit voltage of the lithium battery protection chip, the power management chip will stop charging before the lithium battery protection chip, the lithium battery protection chip will never be triggered, and the maximum voltage cannot be detected in the subsequent voltage sampling error. By "actively increasing the charging cutoff voltage", both the chip sampling error and the actual charging voltage are limited, and the conditions for accurate measurement error and subsequent correction are provided.

[0031] However, the charging cutoff voltage cannot be set too high, which will cause irreversible damage to the energy storage battery, so the preset cutoff voltage needs to be lower than the overcharge protection voltage 4.25V of the energy storage battery. The upper limit value of the charging limit voltage of the lithium battery protection chip can be set, for example, the charging limit voltage is 4.210V~4.240V, and the preset cutoff voltage is 4.240V.

[0032] In other implementation scenarios, the chip sampling error of the power management chip and the charging limit voltage of the lithium battery protection chip can be obtained, and the sum of the chip sampling error and the charging limit voltage is used as the preset cutoff voltage, for example, 4.2V+40mV=4.24V, and the preset cutoff voltage is 4.240V. By setting the preset cutoff voltage=4.24V (close to the protection point 4.210V~4.240V of the lithium battery protection chip), a "critical state" is artificially created to force the lithium battery protection chip to act due to overvoltage protection at a certain time.

[0033] Setting the preset cutoff voltage to "4.2V+40mV=4.24V" is equivalent to reserving the maximum positive space of the sampling error, ensuring that the actual battery voltage has the opportunity to approach or even reach 4.2V in the presence of sampling error, avoiding premature cutoff due to error.

[0034] The preset cut-off voltage is set to "4.2V+40mV=4.24V", which does not pose a risk. The operation of "increasing the charging cut-off voltage" is only used in the voltage learning process (i.e., in step S102) and is not a regular setting for daily charging. The risks of lithium batteries (such as lithium dendrite growth and electrolyte decomposition) are generally positively correlated with "overvoltage amplitude" and "duration". Therefore, in this embodiment, even if the battery voltage of the energy storage battery temporarily exceeds the maximum charging voltage of 4.2V, as long as the time is extremely short (only until the lithium protection chip triggers protection, usually a few seconds to tens of seconds), the chemical reaction has not accumulated to a dangerous level, and no safety problem will occur. The lithium protection MOS tube between the negative electrode of the energy storage battery and the system ground has impedance, and the "voltage" detected by the power management chip is the actual battery voltage + MOS tube voltage drop. Even if the power management chip sets the charging cut-off voltage to 4.24V, the actual battery voltage will be further reduced due to the MOS tube voltage drop. In addition, 4.2V is the conventional limit voltage of lithium batteries, but the battery itself allows a short time to exceed this voltage (such as between 4.2V~4.25V), which will not cause danger.

[0035] S103: Constant current charging is performed on the energy storage device until the lithium protection chip triggers overvoltage protection, and the voltage maximum value of the energy storage battery during the constant current charging process is obtained.

[0036] In a specific implementation scenario, the energy storage device is subjected to constant current charging, and as the amount of electricity in the energy storage battery increases, the voltage of the energy storage battery also increases. Since the charging cut-off voltage of the power management chip has been set to the preset cut-off voltage, the constant current charging process can continue until the voltage of the energy storage battery increases to the triggering value of the lithium protection chip. The voltage maximum value of the battery voltage during the entire constant current charging process is obtained when the lithium protection chip is triggered , the power management chip can continuously monitor the battery voltage of the energy storage battery, and the voltage maximum value of the battery voltage during the entire constant current charging process is obtained when the lithium protection chip is triggered .

[0037] S104: The voltage sampling error of the power management chip is obtained based on the charging limit voltage and the voltage maximum value.

[0038] In a specific implementation scenario, the voltage detection accuracy of the lithium protection chip is significantly better than that of the power management chip, because the lithium protection chip is directly related to the overcharge safety of the lithium battery, and the design standard is strict. When the lithium protection chip is triggered to protect during charging, the actual battery voltage is theoretically equal to the charging limit voltage of the lithium protection chip. The voltage maximum value detected by the power management chip at this time is obtained, and the difference between the voltage maximum value and the charging limit voltage is the voltage sampling error of the power management chip.

[0039] With the higher-precision lithium protection core nominal value as the benchmark, the sampling error of the power management chip can be accurately calculated, so as to offset the deviation through correction, and finally realize the accurate control of the charging cutoff voltage (both overcharging is avoided and the charging speed is improved).

[0040] S105: Collect the real-time charging current of the energy storage device, obtain the voltage correction value based on the real-time charging current and the lithium protection impedance, and obtain the real-time cutoff voltage of the energy storage device according to the voltage correction value and the voltage sampling error.

[0041] In one specific implementation scenario, the real-time charging current of the energy storage device is collected, the voltage correction value is obtained based on the real-time charging current and the lithium protection impedance, and the voltage correction value is the voltage drop of the lithium protection MOS tube when the real-time charging current is This voltage drop makes the voltage detected by the power management chip higher than the actual battery voltage of the energy storage battery.

[0042] In calculating the real-time cutoff voltage, because the real-time cutoff voltage is set by the power management chip, and when the constant current charging changes to constant voltage charging is also managed based on the battery voltage of the energy storage battery detected by the power management chip, the voltage sampling error calculated in the above steps also needs to be considered. The voltage sampling error makes the voltage value collected by the power management chip different from the actual battery voltage value, thereby causing the battery to stop constant current charging too early or overcharging. Specifically, if the voltage sampling error is positive, the voltage value sampled by the power management chip is too high, the power management chip will consider that the voltage of the current energy storage battery has reached the charging cutoff voltage, and thus the constant current charging will be stopped too early and the constant voltage charging will be entered, which will result in low battery charging efficiency. If the voltage sampling error is negative, the power management chip will delay considering that the voltage of the energy storage battery reaches the charging cutoff voltage, and the constant current charging time will be too long, which may cause the battery voltage to exceed the charging limit voltage of the energy storage battery, or even exceed the overcharge protection voltage of the battery, and there is a risk of overcharging, which damages the safety and service life of the battery.

[0043] In one embodiment, the maximum charging voltage (e.g., 4.2V) of the energy storage battery is obtained, and the real-time cutoff voltage is obtained according to the maximum charging voltage, the voltage correction value, and the voltage sampling error. The maximum charging voltage is the critical point of the structural stability of the energy storage battery during charging, which is an absolute safety threshold set by the battery manufacturer.

[0044] Based on the maximum charging voltage, combined with the voltage correction value and the voltage sampling error, the actual voltage value of the energy storage battery can be ensured to reach the maximum charging voltage, and the interference of the voltage drop of the lithium protection MOS tube and the voltage sampling error on the battery voltage value read by the power management chip is eliminated.

[0045] ​In one embodiment, the sum of the maximum charging voltage, the voltage correction value and the voltage sampling error is subtracted by the preset tolerance value to obtain a real-time cutoff voltage. The real-time cutoff voltage can be calculated according to the following formula:

[0046] wherein, is the real-time cutoff voltage, is the real-time charging current, is the lithium protection impedance, is the voltage correction value, is the voltage sampling error, is the preset tolerance value.

[0047] The preset tolerance value is set to enable high-voltage charging without triggering the lithium protection chip. In addition, there are uncalibrated dynamic errors (such as temperature drift, impedance change, and current fluctuation) in the actual system. When the current suddenly changes at the end of the charging period, the voltage drop compensation value may lag behind the update, and the preset tolerance value is set to 10 mV.

[0048] As described above, in the embodiment, the lithium protection MOS tube impedance is obtained, the charging cutoff voltage of the power management chip is set to be higher than the preset cutoff voltage of the charging limit voltage of the lithium protection chip, so that the maximum voltage value when the lithium protection chip is triggered can be obtained. The voltage sampling error of the power management chip is calculated based on the charging limit voltage of the lithium protection chip and the maximum voltage value. The voltage correction value is calculated based on the real-time charging current and the lithium protection impedance. The cutoff voltage is updated in real time by combining the voltage sampling error. Even if the charging current changes (such as from large current to small current), the power management chip can still accurately judge the actual voltage of the battery, avoid "misjudgment cutoff" caused by the voltage drop of the lithium protection MOS tube or the voltage sampling error, thereby prolonging the constant current charging time, reducing the proportion of the constant voltage stage, and ultimately shortening the total charging time and improving the charging efficiency.

[0049] Please refer to Figure 3 , Figure 3 is a structural schematic diagram of one embodiment of the fast charging system provided by the present application. The fast charging system 20 provided by the present application includes the following modules: a charging module 21, a boost module 22, an overvoltage module 23, an error module 24 and a real-time module 25.

[0050] The charging module 21 is configured to charge the energy storage device using the maximum charging power supported by the energy storage device to obtain a lithium protection impedance of the lithium protection MOS tube; the boosting module 22 is configured to boost a preset cutoff voltage of the power management chip to be higher than a charging limit voltage of the lithium protection chip; the overvoltage module 23 is configured to perform constant current charging on the energy storage device until triggering the lithium protection chip to perform overvoltage protection to obtain a maximum voltage value of the energy storage battery in the constant current charging process; the error module 24 is configured to obtain a voltage sampling error of the power management chip based on the preset cutoff voltage and the maximum voltage value; and the real-time module 25 is configured to collect a real-time charging current of the energy storage device, obtain a voltage correction value based on the real-time charging current and the lithium protection impedance, and obtain a real-time cutoff voltage of the energy storage device according to the voltage correction value and the voltage sampling error.

[0051] The real-time module 25 is further configured to obtain a maximum charging voltage of the energy storage battery, and obtain the real-time cutoff voltage according to the maximum charging voltage, the voltage correction value and the voltage sampling error.

[0052] The real-time module 25 is further configured to subtract a preset tolerance value from a sum of the maximum charging voltage, the voltage correction value and the voltage sampling error as the real-time cutoff voltage.

[0053] The boosting module 22 is further configured to obtain a chip sampling error of the power management chip and the charging limit voltage of the lithium protection chip, and take a sum of the chip sampling error and the charging limit voltage as the preset cutoff voltage.

[0054] The charging module 21 is further configured to measure a voltage difference between a negative electrode of the energy storage battery and a ground wire, measure a voltage drop on both sides of the current detection resistor, obtain a current based on the voltage drop and a resistance value of the current detection resistor, and obtain the lithium protection impedance according to the voltage difference and the current.

[0055] The error module 24 is further configured to take a difference between the maximum voltage value and the charging limit voltage as the voltage sampling error.

[0056] As can be seen from the above description, in the embodiment, the lithium protection MOS tube is used to obtain the lithium protection impedance, the charging cutoff voltage of the power management chip is set to be the preset cutoff voltage higher than the charging limit voltage of the lithium protection chip, so that the voltage maximum value when the lithium protection chip is triggered can be obtained, the voltage sampling error of the power management chip is calculated based on the charging limit voltage of the lithium protection chip and the voltage maximum value, the voltage correction value is calculated based on the real-time charging current and the lithium protection impedance, and the cutoff voltage is updated in real time in combination with the voltage sampling error, so that even if the charging current changes (such as from a large current to a small current), the power management chip can still accurately determine the actual voltage of the battery, and the “false cutoff” caused by the voltage drop of the lithium protection MOS tube or the voltage sampling error is avoided, thereby prolonging the constant current charging time, reducing the proportion of the constant voltage stage, ultimately shortening the total charging time, and improving the charging efficiency.

[0057] Please refer toFigure 4 , Figure 4 is a circuit schematic diagram of an embodiment of the control circuit of the energy storage device provided by the present application. The control circuit of the energy storage device 30 comprises an input-output interface 31, a battery pack 32, a lithium battery protection module 33, a battery management module 34, a control chip 35, and a display circuit 36.

[0058] The input-output interface 31 is used to charge or discharge the energy storage device, and the battery pack 32 is used to store electric quantity. The lithium battery protection module 33 is connected to the battery pack 32 and is used to protect the battery pack 32 from overcharging. The battery management module 34 is connected to the input-output interface 32 and the lithium battery protection module 33 and is used to control the charging and discharging current and / or voltage of the battery pack 32 and protect the battery pack 32 from overcharging. The control chip 35 is connected to the battery management module 34 and is used to perform the steps of the method as shown in Figure 1 The display circuit 36 is connected to the control chip 35 and is used to display the operation result of the control chip 35.

[0059] Please refer to Figures 5-7 , Figure 5 is a circuit schematic diagram of an embodiment of the power management chip provided by the present application. The power management chip collects the output current through the CSP2 and CSN2 pins, samples the battery voltage of the energy storage battery through the BAT pin, and communicates with the control chip through the 5385_SCL1 and 5385_SDA1 pins. Figure 6 is a circuit schematic diagram of an embodiment of the lithium battery protection chip provided by the present application. The lithium battery protection chip samples the battery voltage of the energy storage battery through the VC1, VC2, VC3, VC4, and VC5 pins, and controls the lithium battery MOS tube to be turned off through the CO pin to protect the energy storage battery when overvoltage of the battery is detected. Figure 7 is a circuit schematic diagram of an embodiment of the control chip provided by the present application.

[0060] Please refer to Figure 8 , Figure 8 is a structural schematic diagram of another embodiment of the energy storage device provided by the present application. The energy storage device 40 comprises a processor 41 and a memory 42. The processor 41 is coupled to the memory 42. The memory 42 stores a computer program, and the processor 41 executes the computer program to realize the method as above when working. The detailed steps can be referred to the above description and will not be described here.

[0061] Please refer to Figure 9 , Figure 9is a structural schematic diagram of an embodiment of the computer readable storage medium provided by the present application. The computer readable storage medium 50 stores at least one computer program 51, and the computer program 51 is used to be executed by a processor to realize the method as above, and the detailed steps can be referred to the above, which will not be repeated here. In an embodiment, the computer readable storage medium can be a storage chip in a terminal, a hard disk, or a mobile hard disk or an optical disc, and other readable and writable storage tools, and can also be a server and the like.

[0062] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiments can be completed by a computer program instructing related hardware, and the program can be stored in a non-volatile computer readable storage medium. When the program is executed, it can include the processes of the above-mentioned embodiments. Any reference to memory, storage, database or other medium used in the embodiments provided by the present application can include non-volatile and / or volatile memory. Non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM) or flash memory. Volatile memory can include random access memory (RAM) or external cache memory. As an illustration but not limitation, RAM is available in various forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDR SDRAM), enhanced SDRAM (ESDRAM), synchronous link (Synchlink) DRAM (SLDRAM), memory bus (Rambus) direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM) and the like.

[0063] The technical features of the above embodiments can be combined in any way. In order to make the description simple, all possible combinations of the technical features in the above embodiments are not described, but as long as the combination of the technical features does not exist, it should be considered as the scope of the present application.

[0064] It should be understood that the above embodiments are only used to illustrate the technical solutions of the present application, and not to limit them. Those skilled in the art can modify the technical solutions described in the above embodiments, or make equivalent replacement for part of the technical features; all these modifications and replacements shall fall within the protection scope of the appended claims of the present application.

Claims

1. A quick charging method, characterized by, The application is applied to a power storage device, which comprises a power storage battery, a power management chip, a lithium protection chip and a charging circuit connected with the power storage battery respectively, the charging circuit comprises a current detection resistor and a lithium protection MOS connected in series, and the lithium protection chip is connected with the lithium protection MOS; The fast charging method comprises the following steps: charging the power storage device using the maximum charging power supported by the power storage device to obtain the lithium protection impedance of the lithium protection MOS; setting the charging cutoff voltage of the power management chip as a preset cutoff voltage, the preset cutoff voltage being higher than the charging limit voltage of the lithium protection chip; carrying out constant current charging on the power storage device until triggering the lithium protection chip to execute overvoltage protection, obtaining the highest voltage of the power storage battery in the constant current charging process; obtaining the voltage sampling error of the power management chip based on the charging limit voltage and the highest voltage; collecting the real-time charging current of the power storage device, obtaining a voltage correction value based on the real-time charging current and the lithium protection impedance, and obtaining the real-time cutoff voltage of the power storage device according to the voltage correction value and the voltage sampling error.

2. The quick charging method according to claim 1, wherein The step of obtaining the real-time cutoff voltage of the power storage device according to the voltage correction value and the voltage sampling error comprises: obtaining the maximum charging voltage of the power storage battery, and obtaining the real-time cutoff voltage according to the maximum charging voltage, the voltage correction value and the voltage sampling error.

3. The quick charging method according to claim 2, characterized in that, The step of obtaining the real-time cutoff voltage according to the maximum charging voltage, the voltage correction value and the voltage sampling error comprises: taking the sum of the maximum charging voltage, the voltage correction value and the voltage sampling error minus a preset tolerance value as the real-time cutoff voltage.

4. The rapid charging method of claim 1, wherein The step of setting the preset cutoff voltage of the power management chip comprises: obtaining the chip sampling error of the power management chip and the charging limit voltage of the lithium protection chip, and taking the sum of the chip sampling error and the charging limit voltage as the preset cutoff voltage.

5. The quick charging method of claim 1, wherein, After the step of charging the power storage device using the maximum charging power supported by the power storage device to obtain the lithium protection impedance of the lithium protection MOS, the following step is included: measuring the voltage difference between the negative electrode of the power storage battery and the ground wire; measuring the voltage drop on both sides of the current detection resistor, obtaining the current based on the voltage drop and the resistance value of the current detection resistor; obtaining the lithium protection impedance according to the voltage difference and the current.

6. The rapid charging method of claim 1, wherein, The step of obtaining the voltage sampling error of the power management chip based on the charging limit voltage and the highest voltage comprises: taking the difference between the highest voltage and the charging limit voltage as the voltage sampling error.

7. A fast charging system, characterized by, The fast charging method applied to a power storage device comprises the following modules: a charging module, which is used for charging the power storage device using the maximum charging power supported by the power storage device to obtain the lithium protection impedance of the lithium protection MOS; a voltage boosting module, which is used for boosting the preset cutoff voltage of the power management chip, so that the preset cutoff voltage is higher than the charging limit voltage of the lithium protection chip; An overvoltage module is configured to charge the energy storage device with constant current until triggering the lithium protection chip to perform overvoltage protection, and obtain a highest voltage value of the energy storage battery in the constant current charging process; An error module is configured to obtain a voltage sampling error of the power management chip based on the preset cutoff voltage and the highest voltage value; A real-time module is configured to collect a real-time charging current of the energy storage device, obtain a voltage correction value based on the real-time charging current and the lithium protection impedance, and obtain a real-time cutoff voltage of the energy storage device according to the voltage correction value and the voltage sampling error.

8. A control circuit for an energy storage device, characterized by The method comprises the following steps: An input / output interface is configured to charge or discharge the energy storage device; A battery pack is configured to store electric quantity; A lithium protection module is connected to the battery pack and configured to protect the battery pack from overcharging; A battery management module is connected to the input / output interface and the lithium protection module, and configured to control the charging / discharging current and / or voltage of the battery pack and protect the battery pack from overcharging; A control chip is connected to the battery management module, and configured to perform the steps of the method according to any one of claims 1 to 6; A display circuit is connected to the control chip, and configured to display the operation result of the control chip.

9. A computer-readable storage medium, characterized in that, A computer program is stored in a memory, and when the computer program is executed by a processor, the processor is caused to perform the steps of the method according to any one of claims 1 to 6.

10. An energy storage device, characterized by, A memory and a processor are included, and the memory stores a computer program, and when the computer program is executed by the processor, the processor is caused to perform the steps of the method according to any one of claims 1 to 6.

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