A lithium battery charging chip with an adaptive charging strategy and its fabrication method

Abstract

This invention provides a lithium-ion battery charging chip with an adaptive charging strategy and its fabrication method, relating to the fields of battery chip and control technology. The lithium-ion battery charging chip includes an input power adjustment unit, a main charging execution unit, a structured probe current chip injection unit, a battery terminal voltage sampling unit, a charging current sampling unit, a battery temperature sampling unit, a chip temperature sampling unit, a response decomposition unit, a dual-library state observation unit, a lithium intercalation capacity margin calculation unit, a margin corridor control unit, a safety arbitration unit, and a parameter storage unit. In each control cycle, the chip superimposes structured probe current chips into the main charging current. By performing multi-timescale decomposition of the voltage response before and after probe excitation, data is extracted. The lithium intercalation state of the negative electrode surface, the lithium intercalation state of the negative electrode bulk phase, and the lithium intercalation capacity margin parameter are used as a unified core control object, achieving continuous adjustment of the charging trajectory under high charge state, low temperature state, and aging state.

Description

Technical Field

[0001] This invention relates to the field of battery chip and control technology, specifically to a lithium battery charging chip with an adaptive charging strategy and its fabrication method. Background Technology

[0002] Existing lithium battery charging chips generally adopt a segmented control architecture of pre-charge, constant current, constant voltage, and cutoff. Their control core is based on externally measurable parameters such as battery terminal voltage, charging current, time, and temperature. When the battery is in a low state of charge, the ambient temperature is moderate, and the cell is relatively new, this segmented control method can complete basic charging tasks. However, when the battery enters the high state of charge range, low temperature range, or cycle aging range, the mismatch between the ion implantation rate on the negative electrode surface and the diffusion insertion rate inside the negative electrode will significantly intensify. The first bottleneck that appears inside the battery is not the terminal voltage reaching the cutoff threshold, but rather the decreased absorption rate of externally injected lithium ions by the lithium insertion sites on the negative electrode surface and the bulk diffusion channels. This leads to surface ion accumulation, increased interface overpotential, increased local thermal stress, and an increased risk of lithium plating.

[0003] Traditional charging chips, unable to directly observe the dynamic lithium intercalation state differences between the negative electrode surface and the negative electrode bulk phase, typically trigger current reduction with a voltage threshold, protection with a temperature threshold, and termination with a tail current threshold. This type of control logic has three inherent drawbacks. First, terminal voltage and temperature are outcome quantities, not internal bottleneck quantities. By the time the controller detects changes in these outcome quantities, overload has already formed on the negative electrode surface, making feedforward intervention difficult. Second, segmented control, primarily based on fixed threshold switching, struggles to continuously reflect the true acceptance capacity of different individual batteries under varying temperature conditions and aging states. Third, the constant voltage tailing time in the high-charge state region is mainly determined by the surface accumulation release rate within the battery. Traditional fixed cutoff methods cannot balance end-of-charge capacity gains and thermal burden, easily leading to prolonged charging time and reduced battery life. Summary of the Invention

[0004] Technical problems to be solved

[0005] To address the shortcomings of existing technologies, this invention provides a lithium battery charging chip with an adaptive charging strategy and its fabrication method, thus solving the problems of existing technologies.

[0006] Technical solution

[0007] To achieve the above objectives, the present invention is implemented through the following technical solution: a lithium battery charging chip with an adaptive charging strategy, the lithium battery charging chip comprising an input power adjustment unit, a main charging execution unit, a structured probe current chip injection unit, a battery terminal voltage sampling unit, a charging current sampling unit, a battery temperature sampling unit, a chip temperature sampling unit, a response decomposition unit, a dual-library state observation unit, a lithium intercalation capacity margin calculation unit, a margin corridor control unit, a safety arbitration unit, and a parameter storage unit;

[0008] The input power adjustment unit is connected to the external power input terminal and the main charging execution unit, and is used to convert the external input power into controlled charging power.

[0009] The main charging execution unit is connected to the positive and negative terminals of the battery and is used to output the main charging current. ;

[0010] The structured probe current chip injection unit is connected to the control terminal of the main charging execution unit, and is used in the... The main charging current within each control cycle Superimposed structured probe current chip ;

[0011] The battery terminal voltage sampling unit is used to collect the battery terminal voltage sequences before, during, and after the structured probe current chip is applied. ;

[0012] The charging current sampling unit is used to acquire the charging current sequence. The battery temperature sampling unit is used to collect battery temperature data. The chip temperature sampling unit is used to collect the junction temperature of the chip's power region. and the junction temperature of the chip analog region The response decomposition unit is based on the battery terminal voltage sequence. and charging current sequence Extracting transient voltage drop Short window recovery amount Long window recovery volume , Restore the initial slope and restoration curvature The dual-liquidity state observation unit reconstructs the lithium intercalation state of the negative electrode surface based on the following discrete state equation. Lithium intercalation state of the negative electrode :

[0013]

[0014] Indicates the first The lithium intercalation state of the negative electrode surface at the end of each control cycle; Indicates the first The lithium intercalation state quantity inside the negative electrode phase at the end of each control cycle; A conversion factor representing the flux of lithium-ion injection into the surface from the charging current; Indicates the first The main charging current for each control cycle; Indicates the duration of a single control cycle; Indicates the first The diffusion transfer coefficient from the negative electrode surface to the negative electrode bulk phase within one control cycle; This indicates the lithium intercalation concentration difference between the negative electrode surface and the negative electrode bulk phase; This indicates the amount of lithium transferred from the negative electrode surface to the negative electrode phase within one control cycle; Indicates the first The surface embedding coefficient of lithium ions on the negative electrode surface into lattice sites within each control cycle; This indicates the amount of lithium actually embedded in the lattice on the negative electrode surface during one control cycle;

[0015] The lithium intercalation capacity margin calculation unit calculates the first according to the following formula. Lithium intercalation capacity margin parameters for each control cycle :

[0016]

[0017] Indicates the first Lithium intercalation capacity margin parameters for each control cycle; This indicates the absorption and conduction capacity of the negative electrode relative to the lithium accumulation on the negative electrode surface; Indicates the lithium intercalation saturation value on the negative electrode surface; Indicates the remaining lithium intercalation capacity on the negative electrode surface; This indicates the remaining ability of the negative electrode surface to continue intercalating lithium into the crystal lattice; This indicates the surface lithium-ion implantation flux corresponding to the current main charging current; The physical meaning is the difference between the remaining safe capacity of the negative electrode surface for externally injected lithium ions and the current injection flux; the margin corridor control unit is based on... With the preset upper boundary Preset median Preset lower boundary and preset protection boundaries The relative relationship is used to generate the target charging current for the next control cycle. Target peak current Target ascent slope Target recovery time Target voltage approximation slope and target termination current The safety arbitration unit determines the target charging current based on the input voltage, input current, battery terminal voltage, battery temperature, chip power region junction temperature, chip analog region junction temperature, and short-circuit fault status. Target peak current Target ascent slope Target recovery time Target voltage approximation slope and target termination current After constraint trimming, the result is output to the main charging execution unit;

[0018] The parameter storage unit is used to store... , , , , , , , and aging parameters .

[0019] Preferably, the structured probe current chip In the Within each control cycle, the following piecewise function is satisfied:

[0020]

[0021] The first Total output current within each control cycle satisfy:

[0022]

[0023] Indicates the first Local time variables within a control cycle; This represents the first current increment of the step injection section relative to the main charging current. This represents the second current increment of the constant amplitude probe segment relative to the main charging current. Indicates the duration of the step injection section; Indicates the duration of the constant amplitude probe segment; Indicates the duration of the restored observation segment; This represents a structured probe current chip; This represents the total output current after the main charging current and the structured probe current chip are superimposed; the response decomposition unit in Extracting transient voltage drop within the interval ,exist Extracting short window recovery within the interval Long window recovery volume , Restore the initial slope and restoration curvature .

[0024] Preferably, the diffusion transfer coefficient and surface embedding coefficient Determine them according to the following formulas respectively:

[0025]

[0026]

[0027]

[0028] Indicates the first The diffusion transfer coefficient from the negative electrode surface to the negative electrode bulk phase within one control cycle; This represents the initial calibration value of the diffusion transfer coefficient; A fixed weighting coefficient representing the effect of the recovery response ratio on the diffusion transfer coefficient; Indicates the first The recovery amount of a long window in a control cycle; Indicates the first Short-window recovery amount per control cycle; This represents a fixed positive number to prevent the denominator from being zero. This indicates the proportion of restoration achieved by long windows relative to restoration achieved by short windows; A fixed weighting coefficient representing the effect of aging parameters on the diffusion transfer coefficient; Indicates the first Aging parameters for each control cycle; Indicates the first The surface embedding coefficient of lithium ions on the negative electrode surface into lattice sites within each control cycle; This represents the initial calibration value of the surface embedding coefficient; Indicates the activation energy for lithium intercalation on the negative electrode surface; Represents the gas constant; Indicates the first Absolute battery temperature for each control cycle; A fixed weighting coefficient representing the effect of aging parameters on the surface embedding coefficient; Indicates the first Battery temperature in Celsius for each control cycle; It represents the conversion constant between Celsius temperature and thermodynamic temperature.

[0029] Preferably, the dual-liquidity state observation unit determines the surface lithium intercalation state based on the recovered characteristic quantity output by the response decomposition unit. and bulk lithium intercalation state quantity The correction is performed using the following formula:

[0030]

[0031]

[0032]

[0033]

[0034] Indicates the first The correction amount of the lithium intercalation state on the negative electrode surface for each control cycle; This represents the fixed weighting coefficient for the short-window recovery amount in correcting the surface lithium intercalation state; This represents the fixed weighting coefficient used to correct the surface lithium intercalation state by restoring the initial slope; This represents the fixed weighting coefficients used to correct the surface lithium intercalation state by restoring curvature; Indicates the first The correction amount of the lithium intercalation state of the negative electrode phase in each control cycle; This represents the fixed weighting coefficient for the long window recovery amount in correcting the bulk lithium intercalation state; This represents a fixed weighting coefficient that indicates the difference between the long-window recovery amount and the short-window recovery amount in terms of the correction of the bulk lithium intercalation state; This represents the fixed weighting coefficient for the correction of bulk lithium intercalation state by the restoration curvature; This represents the difference between the long-timescale recovery and the short-timescale recovery. This indicates the corrected lithium intercalation state on the negative electrode surface; This represents the corrected lithium intercalation state of the negative electrode phase; the dual-liquidity state observation unit uses Alternative ,use Alternative The state is recursively pushed into the next control cycle.

[0035] Preferably, the lithium intercalation capacity margin calculation unit calculates the thermal correction amount based on the battery temperature, the junction temperature of the chip power region, and the junction temperature of the chip simulation region. The thermal correction formula is as follows:

[0036]

[0037]

[0038] Indicates the first Thermal correction amount per control cycle; A fixed thermal correction factor representing the effect of internal temperature difference on lithium intercalation capacity margin; This represents the temperature difference between the junction temperature of the chip's power region and the junction temperature of the chip's analog region. A fixed thermal correction factor representing the effect of the battery's external thermal state on the lithium intercalation capacity margin; This represents the temperature difference between the battery temperature and the junction temperature of the chip's analog region. This represents the lithium intercalation capacity margin parameter after thermal correction; This indicates the safety margin corresponding to thermal stress deducted from the uncorrected lithium intercalation capacity margin.

[0039] Preferably, the margin corridor control unit is based on the thermally corrected lithium intercalation capacity margin parameter. The target charging current is generated according to the following piecewise control law. :

[0040]

[0041] The margin corridor control unit generates the target peak current according to the following saturation mapping law. Target ascent slope Target recovery time Target voltage approximation slope and target termination current :

[0042]

[0043]

[0044]

[0045]

[0046]

[0047] The saturation function satisfy:

[0048]

[0049] Indicates the thermally corrected first Each control cycle has a lithium intercalation capacity margin parameter. Indicates the upper boundary of the margin corridor; This represents the median of the margin corridor; Indicates the lower boundary of the margin corridor; Indicates the protection boundary; This represents the flow control coefficient when the margin is higher than the upper boundary; This represents the flow reduction control coefficient when the margin is lower than the lower boundary. This represents the margin of change rate suppression coefficient; It represents the absolute value of the rate of change of lithium intercalation capacity margin between two adjacent control cycles; Indicates the protection charging current; , , , , These represent the calibration values ​​of the target peak current, target rise slope, target recovery time, target voltage approach slope, and target termination current at the median of the margin corridor, respectively. , , , , , , , , , These represent the minimum and maximum boundary values ​​of the corresponding control variables, respectively. , , , , These represent the mapping coefficients of lithium intercalation capacity margin to the target peak current, target rise slope, target recovery time, target voltage approach slope, and target termination current, respectively.

[0050] Preferably, the aging parameters in the parameter storage unit According to the The historical characteristics after the end of the second charge are updated using the following formula:

[0051]

[0052] Indicates the first Aging parameters after the first charge; Indicates the first Aging parameters before the start of the next charge; The aging weighting coefficient represents the decay time constant of the constant pressure wake. Indicates the first The wake decay time constant during the constant voltage stage at the end of the second charge; The aging weighting coefficient represents the temperature rise gain per unit charge. Indicates the first Temperature rise gain corresponding to the unit charge input per charge; An aging weighting coefficient representing the ratio of long window recovery to short window recovery; Indicates the first Recovery amount during the long window during the second charge; Indicates the first Short-window recovery amount during the second charge; This represents a fixed positive number to prevent the denominator from being zero. The aging weighting coefficient represents the charging time drift within the preset state of charge interval; Indicates the first The charging time drift during the second charge within the preset state of charge range; the aging parameters Used to correct the process during the next charge. , and .

[0053] Preferably, the adaptive charging control method for a lithium battery charging chip with an adaptive charging strategy includes the following steps:

[0054] Sp1: The input power regulation unit receives external power, and the main charging execution unit outputs the initial main charging current to the lithium battery to be charged. ;

[0055] Sp2, the structured probe current fragment injection unit in the first The initial main charging current within each control cycle Superimposed structured probe current chip And form the total output current. ;

[0056] Sp3, Battery Terminal Voltage Sampling Unit acquires battery terminal voltage sequence The charging current sampling unit collects the charging current sequence. The battery temperature sampling unit collects the battery temperature. The chip temperature sampling unit collects the junction temperature of the chip's power region. and the junction temperature of the chip analog region ;

[0057] Sp4, the response decomposition unit from the battery terminal voltage sequence Extracting transient pressure drop Short window recovery amount Long window recovery volume , Restore the initial slope and restoration curvature ;

[0058] Sp5, the dual-reservoir status observation unit, based on the transient pressure drop... Short window recovery amount Long window recovery volume , Restore the initial slope Restoring curvature Battery temperature and aging parameters Calculate the surface lithium intercalation state. and bulk lithium intercalation state quantity ;

[0059] Sp6, the lithium intercalation capacity margin calculation unit is based on the surface lithium intercalation state quantity Bulk lithium intercalation state quantity Main charging current diffusion transfer coefficient Surface embedding coefficient Lithium saturation value on the negative electrode surface Chip power region junction temperature Chip analog region junction temperature and battery temperature Calculate the thermally corrected lithium intercalation capacity margin parameters ;

[0060] Sp7, the margin corridor control unit is based on the thermally corrected lithium intercalation capacity margin parameters. Generate the target charging current for the next control cycle. Target peak current Target ascent slope Target recovery time Target voltage approximation slope and target termination current ;

[0061] Sp8, the safety arbitration unit performs constraint trimming on the target parameters obtained in step Sp7, and drives the main charging execution unit to output the corresponding charging trajectory, and then returns to step Sp2 to enter the next control cycle.

[0062] Preferably, after performing step Sp7, when the battery state of charge meets the requirements... And the thermally corrected lithium intercalation capacity margin parameter satisfies When this happens, perform the following steps:

[0063] Sp9 and the margin corridor control unit switch the charging trajectory to a guided charging trajectory, which satisfies the following piecewise function:

[0064]

[0065] Indicates the first Battery state of charge for each control cycle; This represents the state of charge threshold for entering the high-charge state region; Indicates the first The guided charging trajectory current within each control cycle; Indicates the ramp initiation current; Indicates the ramp termination current and holding current; Indicates the duration of the uphill section of the slope; Indicates the duration of the constant value period; Indicates the duration of the restored observation segment; Indicates that within the ascending section of the slope, from linearly rising to The current increment;

[0066] Sp10, the response decomposition unit re-extracts the transient voltage drop under the guided charging trajectory. Short window recovery amount Long window recovery volume , Restore the initial slope and restoration curvature The dual-liquidity state observation unit recalculates the surface lithium intercalation state quantities. and bulk lithium intercalation state quantity The lithium intercalation capacity margin calculation unit recalculates the thermally corrected lithium intercalation capacity margin parameters. ;

[0067] Sp11, when the recalculated thermally corrected lithium intercalation capacity margin parameter satisfies When the time is right, exit the guided charging trajectory and return to step Sp7; when the recalculated thermally corrected lithium intercalation capacity margin parameter satisfies If necessary, return to step Sp9 to continue executing the guided charging trajectory.

[0068] Preferably, the method for fabricating a lithium battery charging chip with an adaptive charging strategy includes the following steps:

[0069] Sp1, divide the semiconductor substrate into a high-voltage power region, a low-noise analog region, and a digital control region;

[0070] Sp2, a deep trench isolation structure and a deep well shielding structure are formed between the high-voltage power region and the low-noise simulation region;

[0071] Sp3, forming high-voltage LDMOS devices, driver devices and power metal interconnects corresponding to the input power regulation unit, main charging execution unit and structured probe current chip injection unit in the high-voltage power region;

[0072] Sp4, low offset operational amplifiers, reference sources, sample-and-hold circuits, analog-to-digital converters, and analog matching resistor-capacitor arrays are formed in the low-noise analog region for the battery terminal voltage sampling unit, charging current sampling unit, battery temperature sampling unit, chip temperature sampling unit, and response decomposition unit.

[0073] Sp5, in the digital control area, digital logic circuits, timing control circuits and non-volatile memory are formed corresponding to the dual-library state observation unit, lithium intercalation capacity margin calculation unit, margin corridor control unit, security arbitration unit and parameter storage unit.

[0074] Sp6. A first on-chip temperature node is formed near the power switch region, and a second on-chip temperature node is formed near the analog sampling region. A fixed thermal coupling relationship is established between the first on-chip temperature node and the power switch region, and between the second on-chip temperature node and the analog sampling region, through a metal thermal diffusion path.

[0075] Sp7 performs dynamic calibration on the battery terminal voltage sampling unit, charging current sampling unit, battery temperature sampling unit, chip temperature sampling unit, and response decomposition unit, and then converts the calibrated data into the final output. , , , , , , , , , , , , , , , , , , , , , and Write to the parameter storage unit;

[0076] Sp8. The calibrated chip is packaged to obtain the lithium battery charging chip with the adaptive charging strategy.

[0077] Beneficial effects

[0078] This invention provides a lithium-ion battery charging chip with an adaptive charging strategy and its fabrication method. It has the following beneficial effects:

[0079] 1. This invention transforms the controlled object from an externally measurable result quantity into an internal bottleneck quantity. Lithium intercalation state quantity on the negative electrode surface. Directly reflects the degree of lithium-ion accumulation on the negative electrode surface, and the lithium intercalation state of the negative electrode bulk phase. Directly reflects the diffusion absorption capacity inside the negative electrode, and is a parameter for lithium intercalation capacity margin. It directly reflects the remaining safe capacity under the current injection conditions, so the control basis is closer to the electrochemical essence.

[0080] 2. This invention unifies the normal charging process and the online identification process within the same power channel using structured probe current chips, eliminating the need for additional charging disconnection or external testing equipment, thus facilitating chip-level implementation. Because the amplitude and duration of the probe chips are controlled, the identification process does not disrupt the continuity of the main charging path.

[0081] 3. This invention incorporates thermal correction and aging correction into a unified parameter system. Thermal correction distinguishes between chip self-heating and battery thermal state, avoiding false protection; aging correction updates parameters based on the constant voltage wake current time constant, temperature rise gain, and recovery characteristic drift during each charge, enabling the same chip to continuously adapt to the degradation process of the same battery during long-term use. Attached Figure Description

[0082] Figure 1 This is a block diagram of the overall structure of the lithium battery charging chip of the present invention;

[0083] Figure 2 This is a schematic diagram of the structured probe current chip and voltage response;

[0084] Figure 3 A schematic diagram of the dual-liquidity intercalation state model and the formation mechanism of the lithium intercalation capacity margin;

[0085] Figure 4 This is a flowchart of the charging control based on lithium intercalation capacity margin. Detailed Implementation

[0086] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Specific Implementation Example 1:

[0088] like Figures 1 to 4 As shown, a lithium battery charging chip with an adaptive charging strategy and its fabrication method are disclosed. The chip includes an input power adjustment unit, a main charging execution unit, a structured probe current chip injection unit, a battery terminal voltage sampling unit, a charging current sampling unit, a battery temperature sampling unit, a chip temperature sampling unit, a response decomposition unit, a dual-library state observation unit, a lithium intercalation capacity margin calculation unit, a margin corridor control unit, a safety arbitration unit, and a parameter storage unit. Figure 1The signal flow and control flow relationship is given: the external power supply enters the main charging execution unit through the input power regulation unit. The main charging execution unit outputs the main charging current to the lithium battery to be charged on the one hand, and receives modulation from the structured probe current chip injection unit on the other hand. The battery terminal voltage, charging current, battery temperature and chip temperature are synchronously sampled and input to the response decomposition unit. The feature quantities obtained by the response decomposition unit enter the dual-library state observation unit, and the dual-library state observation unit outputs... and ;Calculation of lithium intercalation capacity margin by the calculation unit and The margin corridor control unit generates the target trajectory accordingly; the safety arbitration unit performs boundary trimming on the target trajectory; and the parameter storage unit provides the state observation and control unit with factory calibration parameters, aging parameters, and boundary parameters.

[0089] At the hardware implementation level, the main charging execution unit adopts a synchronous buck power stage, and the structured probe current chip injection unit shares the power path with the main charging execution unit but independently controls the gate timing; the battery terminal voltage sampling unit and the charging current sampling unit ensure time alignment through synchronous sampling triggering; the chip temperature sampling unit includes on-chip temperature nodes in the power region and on-chip temperature nodes in the analog region, where the temperature nodes in the power region are used to characterize the internal thermal stress caused by switching losses, and the temperature nodes in the analog region are used to provide a low-noise reference temperature; the parameter storage unit adopts a non-volatile memory structure to save the factory coefficients and the aging parameters accumulated during operation.

[0090] The structured probe current chip design involves the controller superimposing a structured probe current chip onto the main charging current in each control cycle. The probe chip employs a three-segment structure: the first segment is a step-current injection segment, the second segment is a constant-amplitude probe segment, and the third segment is a recovery observation segment. Its mathematical form is as follows:

[0091]

[0092]

[0093] In the formula, Indicates the first Structured probe current chip within each control cycle; Indicates the control cycle number; Indicates a local time within the control cycle; This indicates the increment of current in the step injection section; This indicates the current increment of the constant amplitude probe segment; Indicates the duration of the step injection section; Indicates the duration of the constant amplitude probe segment; Indicates the duration of the restored observation segment; This indicates the total current output to the battery terminal; This indicates the main charging current.

[0094] The physical significance of the three-segment probe is as follows: the step injection segment is used to excite the surface ohmic response and the interface rapid polarization response in a very short time; the constant amplitude probe segment is used to generate a limited amplitude surface lithium intercalation perturbation without significantly disrupting the overall charging process; and the recovery observation segment is used to observe the surface accumulation release and bulk diffusion compensation after the probe excitation is stopped. Through this design, the same probe fragment provides information sources on three time scales simultaneously.

[0095] The base current of the main charging execution unit With probe current increment , The following constraints must be satisfied:

[0096]

[0097]

[0098]

[0099] In the formula, This represents the probe occupancy ratio limitation coefficient; This represents the duration of a complete control cycle; the above constraints ensure that the probe chip can elicit an observable response without causing the total current waveform to deviate from the safe boundaries.

[0100] Figure 2 The voltage response waveform under structured probe current fragment excitation is shown. The response decomposition unit extracts five fundamental features from the sampling sequence, namely transient voltage drop. Short window recovery amount Long window recovery volume , Restore the initial slope and restoration curvature .

[0101] The transient voltage drop is calculated using the following formula:

[0102]

[0103] In the formula, Indicates the first Transient voltage drop per control cycle; This represents the battery terminal voltage at the instant before the step injection begins; This represents the battery terminal voltage at the instant after the step injection begins; Indicates the start time of the step injection; symbol Represents the limit value before time; symbol This represents the limit value after a certain time. This quantity mainly reflects the combined result of the loop ohmic voltage drop and the rapid surface polarization.

[0104] The short window recovery amount and the long window recovery amount are calculated using the following formulas:

[0105]

[0106]

[0107] In the formula, Indicates the first Short-window recovery amount per control cycle; Indicates the first The recovery amount of a long window in a control cycle; Indicates the start time of the restored observation segment; Indicates the duration of short-window observation; Indicates the duration of long-window observation, and satisfies ; This indicates the battery terminal voltage at the very beginning of the recovery observation period; This indicates the battery terminal voltage corresponding to the short window duration after the start of the recovery observation period; This represents the battery terminal voltage corresponding to the duration of the long window after the start of the recovery observation period. The short window recovery value mainly characterizes the surface polarization release rate, while the long window recovery value mainly characterizes the bulk diffusion compensation capability.

[0108] The initial slope is calculated using the following formula:

[0109]

[0110] In the formula, Indicates the first The initial recovery slope for each control cycle; numerator The denominator represents the voltage change within the short window; This indicates the duration of the short window. The larger the slope, the faster the recovery process.

[0111] The curvature recovery is calculated using the following discrete second-order difference form:

[0112]

[0113] In the formula, Indicates the first The recovery curvature of each control cycle; The numerator represents the battery terminal voltage at the halfway point of the recovery observation period; the numerator represents the second-order difference term; and the denominator represents the normalized time scale. This curvature is used to characterize the degree of bending of the recovered waveform and can distinguish between single fast recovery and multi-stage recovery.

[0114] pass , , , and The combination of these components allows the response decomposition unit to split the total voltage response into ohmic components, surface polarization components, and bulk diffusion components, providing input for subsequent state observations.

[0115] Figure 3 This paper illustrates the dual-liquidity intercalation state model used in this invention. The model treats the negative electrode as two coupled lithium storage sites: a surface lithium storage site in direct contact with the electrolyte and a bulk lithium storage site responsible for inward diffusion absorption. Surface lithium intercalation state quantities... Describes the degree of lithium occupancy on the negative electrode surface, and the bulk lithium intercalation state parameters. Describes the average degree of lithium intercalation inside the negative electrode.

[0116] The discrete state recurrence equation is as follows:

[0117]

[0118]

[0119] In the formula, the first term This indicates the amount of lithium intercalated on the surface at the end of the previous cycle; the second term This indicates the amount of lithium injected into the surface by the external main charging current during this cycle; the third item. Indicates the amount of lithium transferred from the surface to the bulk phase; Item 4 This indicates the amount of lithium that has entered the crystal lattice and is stably intercalated from the surface. The second item on the right represents the amount of new absorption in the body phase.

[0120] In practical implementation, recursive equations alone cannot offset model errors and sampling errors, so a correction mechanism based on recovered features is introduced:

[0121]

[0122]

[0123]

[0124]

[0125] In the formula, Indicates the surface condition correction amount; Indicates the correction amount for the phase state; , , , , , These are the factory calibration coefficients; Indicates the corrected surface condition; This represents the corrected bulk phase state. The mechanism is that the short-window recovery amount and the initial recovery slope are primarily sensitive to surface processes, while the long-window recovery amount and the difference between the long and short windows are primarily sensitive to bulk diffusion processes. Therefore, they are used to correct... and .

[0126] To enable the dual-reservoir state observation model to adapt to different temperatures, aging levels, and diffusion-confined states, the diffusion transfer coefficient... With surface embedding coefficient It is not a constant, but is determined by a combination of recovery characteristics and aging parameters.

[0127] The diffusion transfer coefficient is calculated using the following formula:

[0128]

[0129] In the formula, This is the initial value for the diffusion transfer coefficient; Weight the ratio of long to short windows; It reflects the degree of hysteresis between bulk diffusion and surface recovery; For aging weight; These are aging parameters; To prevent positive numbers with a denominator of zero. A larger recovery value for the long window and a smaller recovery value for the short window indicates slower volume compensation. The smaller the value, the larger the aging parameter, indicating more severe degradation of the diffusion pathway. The smaller.

[0130] The surface embedding coefficient is calculated using the following formula:

[0131]

[0132]

[0133] In the formula, The initial values ​​for the surface embedding coefficients; The activation energy for lithium intercalation on the negative electrode surface; It is the gas constant; Absolute temperature; This represents the weighting of aging parameters on the attenuation of surface embedding capability. This formula reflects the principle that the surface embedding process weakens as temperature decreases and as aging progresses.

[0134] The lithium intercalation capacity margin parameter is the core control quantity of this invention, defined as "the absorption and continued intercalation capability of the negative electrode's internal surface deposits" minus "the surface injection flux generated by the external main charging current." Specifically:

[0135]

[0136] In the formula, the first term The second term represents the conductivity of the volume relative to the surface deposits; This indicates the acceptance capacity of remaining surface intercalation sites for further lithium intercalation; the third term... This represents the injected flux caused by the current main charging current. If... A large positive value indicates that the current injection flow is lower than the internal absorption capacity; if Approaching zero indicates that the surface is nearing its capacity limit; if A negative value indicates surface deposition, significantly increasing the risk of lithium plating.

[0137] Since chip power loss and battery thermal state both affect the actual safety margin, thermal correction is introduced:

[0138]

[0139]

[0140] In the formula, Indicates thermal correction amount; Indicates the weight of the influence of temperature difference inside the chip; This indicates the temperature difference between the chip's power region and analog region. This item is used to characterize the internal additional thermal stress caused by switching losses. Indicates the weight of the influence of the battery's external thermal state; This represents the difference between the battery temperature and the reference temperature of the chip's analog area. This item is used to characterize the thermal state of the battery itself. This indicates the lithium intercalation capacity margin parameter after thermal correction. After thermal correction, the controller can distinguish between "local thermal burden caused by chip self-heating" and "deterioration of safety margin caused by battery degradation".

[0141] Thermally corrected lithium intercalation capacity margin parameters As the sole core control variable, the controller has four preset boundaries: the upper boundary of the margin corridor. Margin Corridor Median Lower boundary of the margin corridor and protect the boundary The piecewise control law for the target charging current is as follows:

[0142]

[0143] In the formula, Indicates the high margin current increase coefficient; Indicates the low margin flow reduction coefficient; This represents the margin of change rate suppression coefficient; Indicates the protective current. When When the current is above the upper boundary, it indicates that the internal accepting capacity is excessive, and the controller increases the main charging current; when... When falling into the middle area of ​​the corridor, maintain the current; when As the trajectory approaches the lower boundary, the controller reduces the current and introduces a rate-of-change penalty term, causing the trajectory to slow down earlier; when When the current drops below the protection boundary, a safe current is forcibly applied.

[0144] Besides the target charging current, the other control quantities are also... The driver and mapping relationship are as follows:

[0145]

[0146]

[0147]

[0148]

[0149]

[0150] In the above formula, The target peak current for the next cycle; The current ramp-up slope for the next cycle; For recovery time; The slope is used to approximate the terminal voltage. To terminate the current; The saturation function is used to limit the control quantity within permissible boundaries. Therefore, this invention does not simply reduce the average current, but simultaneously adjusts the peak value, slope, recovery time, and termination conditions to achieve complete trajectory shaping.

[0151] Surface deposits are most easily formed in the high-charge state region. When the following conditions are met... and At this time, the controller does not directly enter the traditional constant voltage tailing mode, but instead switches to the guided charging trajectory, the mathematical form of which is as follows:

[0152]

[0153] In the formula, Indicates the ramp initiation current; Indicates the ramp termination current; Indicates the duration of the rising phase; Indicates the duration of the hold segment; This indicates the duration of the recovery phase. The purpose of the guided charging mode is to preferentially transfer lithium from the surface lithium-intercalated pool to the bulk phase through a lower peak value and a longer recovery phase, thus slowing down further accumulation. See the control process below. Figure 4 .

[0154] During the execution of the guided charging mode, the system continuously re-extracts... , , , and Recalculate , and .when rebounded to If the above is true, return to normal margin corridor control; if Still below If the charging mode switch is not directly related to the internal bottleneck state, then the guided trajectory will continue. This process links the charging mode switch directly to the internal bottleneck state, rather than to a fixed voltage threshold.

[0155] To ensure the chip continues to adapt to battery degradation after multiple cycles, an aging parameter update mechanism is implemented:

[0156]

[0157] In the formula, Indicates the first Aging parameters after the first charge; Indicates the aging parameters to be used in the next charge; This represents the constant pressure wake decay time constant; Indicates the temperature rise gain per unit charge input; This indicates the degree of hysteresis between bulk recovery and surface recovery; This represents the charging time drift within the preset state-of-charge range. The four quantities above correspond to deterioration in end-of-charge tailing, thermal load, diffusion compensation, and capacity acceptance, respectively. With... Increase and Automatically decrease More sensitive to the same injection flow, the system therefore adopts a conservative trajectory in advance.

[0158] To accurately determine the high-charge state region in the guided charging mode, the chip internally performs a synchronous state-of-charge estimation, the formula of which is:

[0159]

[0160] In the formula, Indicates the first State of charge for each control cycle; Indicates the state of charge for the next cycle; Indicates charging coulombic efficiency; This indicates the currently estimated available capacity. For a single unit with a rated capacity of... For lithium-ion batteries, select the control cycle Probe chip element parameters , , The initial value of the main charging current is taken as The high charge state threshold is taken as At ambient temperature When the battery is relatively fresh, the controller will... Long-term higher than The stages gradually improve ; cooled to ambient temperature At that time, due to It decreases as absolute temperature decreases. Automatic shifting will shorten the peak current duty cycle and extend the recovery time; in the later stages of cyclic aging, due to To improve, the system will reduce and This reduces the intensity of the charging trajectory.

[0161] The chip is fabricated using a BCD process. First, a high-voltage power region, a low-noise analog region, and a digital control region are defined on the semiconductor substrate. Then, a deep trench isolation structure and a deep well shielding structure are formed between the high-voltage power region and the low-noise analog region to block switching noise coupling to the sampling link. Next, a synchronous buck power stage, probe current injection branch, and power drive stage are formed in the high-voltage power region; voltage sampling, current sampling, temperature sampling, and analog-to-digital conversion circuits are formed in the low-noise analog region; and state observation logic, margin calculation logic, corridor control logic, security arbitration logic, and non-volatile memory are formed in the digital control region.

[0162] In chip layout design, the power region temperature node is placed near the high-side power devices, while the analog region temperature node is placed near the bandgap reference and analog-to-digital converter, so that they respectively reflect the power heat source and the low-noise reference heat source. Before packaging, [the following is done]... , , , , , , , , , , , , , , , , , , , , , and Dynamic calibration is performed and the data is written to the parameter storage unit. After packaging, the chip has online identification and closed-loop control functions.

[0163] Figure 4 The process shown corresponds to the following steps.

[0164] Sp1: Receives external power and outputs initial main charging current;

[0165] Sp2, Injection of structured probe current chip;

[0166] Sp3: Collects voltage, current, battery temperature, and chip temperature;

[0167] SP4, Extraction , , , and ;

[0168] SP5, Update , , and ;

[0169] Sp6, Calculation With thermal correction ;

[0170] Sp7. Generate the target charging trajectory based on the margin corridor;

[0171] SP8, secure arbitration and perform charging;

[0172] Sp9, when and Switch to a guided charging trajectory as needed;

[0173] Sp10, Re-observe and calculate ;

[0174] Sp11, when Exit the guided charging trajectory and return to step Sp7. Return to step Sp9.

[0175] The above process is executed in a closed loop within each control cycle, forming a... A continuous trajectory control system with [the following] as its core.

[0176] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising a reference structure" does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes the element.

[0177] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A lithium battery charging chip with an adaptive charging strategy, characterized in that: The lithium battery charging chip includes an input power adjustment unit, a main charging execution unit, a structured probe current chip injection unit, a battery terminal voltage sampling unit, a charging current sampling unit, a battery temperature sampling unit, a chip temperature sampling unit, a response decomposition unit, a dual-library state observation unit, a lithium intercalation capacity margin calculation unit, a margin corridor control unit, a safety arbitration unit, and a parameter storage unit. The input power adjustment unit is connected to the external power input terminal and the main charging execution unit, and is used to convert the external input power into controlled charging power. The main charging execution unit is connected to the positive and negative terminals of the battery and is used to output the main charging current. ; The structured probe current chip injection unit is connected to the control terminal of the main charging execution unit, and is used in the... The main charging current within each control cycle Superimposed structured probe current chip ; The battery terminal voltage sampling unit is used to collect the battery terminal voltage sequences before, during, and after the structured probe current chip is applied. ; The charging current sampling unit is used to acquire the charging current sequence. The battery temperature sampling unit is used to collect battery temperature data. The chip temperature sampling unit is used to collect the junction temperature of the chip's power region. and the junction temperature of the chip analog region ; The response decomposition unit is based on the battery terminal voltage sequence. and charging current sequence Extracting transient voltage drop Short window recovery amount Long window recovery volume , Restore the initial slope and restoration curvature The dual-liquidity state observation unit reconstructs the lithium intercalation state of the negative electrode surface based on the following discrete state equation. Lithium intercalation state of the negative electrode : Indicates the first The lithium intercalation state of the negative electrode surface at the end of each control cycle; Indicates the first The lithium intercalation state quantity inside the negative electrode phase at the end of each control cycle; A conversion factor representing the flux of lithium-ion injection into the surface from the charging current; Indicates the first The main charging current for each control cycle; Indicates the duration of a single control cycle; Indicates the first The diffusion transfer coefficient from the negative electrode surface to the negative electrode bulk phase within one control cycle; This indicates the lithium intercalation concentration difference between the negative electrode surface and the negative electrode bulk phase; This indicates the amount of lithium transferred from the negative electrode surface to the negative electrode phase within one control cycle; Indicates the first The surface embedding coefficient of lithium ions on the negative electrode surface into lattice sites within each control cycle; This indicates the amount of lithium actually embedded in the lattice on the negative electrode surface during one control cycle; The lithium intercalation capacity margin calculation unit calculates the first according to the following formula. Lithium intercalation capacity margin parameters for each control cycle : Indicates the first Lithium intercalation capacity margin parameters for each control cycle; This indicates the absorption and conduction capacity of the negative electrode relative to the lithium accumulation on the negative electrode surface; Indicates the lithium intercalation saturation value on the negative electrode surface; Indicates the remaining lithium intercalation capacity on the negative electrode surface; This indicates the remaining ability of the negative electrode surface to continue intercalating lithium into the crystal lattice; This indicates the surface lithium-ion implantation flux corresponding to the current main charging current; The physical meaning is the difference between the remaining safe capacity of the negative electrode surface for externally injected lithium ions and the current injection flux; the margin corridor control unit is based on... With the preset upper boundary Preset median Preset lower boundary and preset protection boundaries The relative relationship is used to generate the target charging current for the next control cycle. Target peak current Target ascent slope Target recovery time Target voltage approximation slope and target termination current ; The safety arbitration unit determines the target charging current based on the input voltage, input current, battery terminal voltage, battery temperature, chip power region junction temperature, chip analog region junction temperature, and short-circuit fault status. Target peak current Target ascent slope Target recovery time Target voltage approximation slope and target termination current After constraint trimming, the result is output to the main charging execution unit; The parameter storage unit is used to store... , , , , , , , and aging parameters .

2. The lithium battery charging chip with an adaptive charging strategy according to claim 1, characterized in that: The structured probe current chip In the Within each control cycle, the following piecewise function is satisfied: The first Total output current within each control cycle satisfy: Indicates the first Local time variables within a control cycle; This represents the first current increment of the step injection section relative to the main charging current. This represents the second current increment of the constant amplitude probe segment relative to the main charging current. Indicates the duration of the step injection section; Indicates the duration of the constant amplitude probe segment; Indicates the duration of the restored observation segment; This represents a structured probe current chip; This represents the total output current after the main charging current and the structured probe current chip are superimposed; the response decomposition unit in Extracting transient voltage drop within the interval ,exist Extracting short window recovery within the interval Long window recovery volume , Restore the initial slope and restoration curvature .

3. The lithium battery charging chip with an adaptive charging strategy according to claim 1, characterized in that: The diffusion transfer coefficient and surface embedding coefficient Determine them according to the following formulas respectively: Indicates the first The diffusion transfer coefficient from the negative electrode surface to the negative electrode bulk phase within one control cycle; This represents the initial calibration value of the diffusion transfer coefficient; A fixed weighting coefficient representing the effect of the recovery response ratio on the diffusion transfer coefficient; Indicates the first The recovery amount of a long window in a control cycle; Indicates the first Short-window recovery amount per control cycle; This represents a fixed positive number to prevent the denominator from being zero. This indicates the proportion of restoration achieved by long windows relative to restoration achieved by short windows; A fixed weighting coefficient representing the effect of aging parameters on the diffusion transfer coefficient; Indicates the first Aging parameters for each control cycle; Indicates the first The surface embedding coefficient of lithium ions on the negative electrode surface into lattice sites within each control cycle; This represents the initial calibration value of the surface embedding coefficient; Indicates the activation energy for lithium intercalation on the negative electrode surface; Represents the gas constant; Indicates the first Absolute battery temperature for each control cycle; A fixed weighting coefficient representing the effect of aging parameters on the surface embedding coefficient; Indicates the first Battery temperature in Celsius for each control cycle; It represents the conversion constant between Celsius temperature and thermodynamic temperature.

4. The lithium battery charging chip with an adaptive charging strategy according to claim 1, characterized in that: The dual-liquidity state observation unit determines the surface lithium intercalation state based on the recovered characteristic quantity output by the response decomposition unit. and bulk lithium intercalation state quantity The correction is performed using the following formula: Indicates the first The correction amount of the lithium intercalation state on the negative electrode surface for each control cycle; This represents the fixed weighting coefficient for the short-window recovery amount in correcting the surface lithium intercalation state; This represents the fixed weighting coefficient used to correct the surface lithium intercalation state by restoring the initial slope; This represents the fixed weighting coefficients used to correct the surface lithium intercalation state by restoring curvature; Indicates the first The correction amount of the lithium intercalation state of the negative electrode phase in each control cycle; This represents the fixed weighting coefficient for the long window recovery amount in correcting the bulk lithium intercalation state; This represents a fixed weighting coefficient that indicates the difference between the long-window recovery amount and the short-window recovery amount in terms of the correction of the bulk lithium intercalation state; This represents the fixed weighting coefficient for the correction of bulk lithium intercalation state by the restoration curvature; This represents the difference between the long-timescale recovery and the short-timescale recovery. This indicates the corrected lithium intercalation state on the negative electrode surface; This represents the corrected lithium intercalation state of the negative electrode phase; the dual-liquidity state observation unit uses Alternative ,use Alternative The state is recursively pushed into the next control cycle.

5. A lithium battery charging chip with an adaptive charging strategy according to claim 1, characterized in that: The lithium intercalation capacity margin calculation unit calculates the thermal correction amount based on the battery temperature, the junction temperature of the chip power region, and the junction temperature of the chip simulation region. The thermal correction formula is as follows: Indicates the first Thermal correction amount per control cycle; A fixed thermal correction factor representing the effect of internal temperature difference on lithium intercalation capacity margin; This represents the temperature difference between the junction temperature of the chip's power region and the junction temperature of the chip's analog region. A fixed thermal correction factor representing the effect of the battery's external thermal state on the lithium intercalation capacity margin; This represents the temperature difference between the battery temperature and the junction temperature of the chip's analog region. This represents the lithium intercalation capacity margin parameter after thermal correction; This indicates the safety margin corresponding to thermal stress deducted from the uncorrected lithium intercalation capacity margin.

6. The lithium battery charging chip with an adaptive charging strategy according to claim 1, characterized in that: The margin corridor control unit is based on the thermally corrected lithium intercalation capacity margin parameter. The target charging current is generated according to the following piecewise control law. : The margin corridor control unit generates the target peak current according to the following saturation mapping law. Target ascent slope Target recovery time Target voltage approximation slope and target termination current : The saturation function satisfy: Indicates the thermally corrected first Each control cycle has a lithium intercalation capacity margin parameter. Indicates the upper boundary of the margin corridor; This represents the median of the margin corridor; Indicates the lower boundary of the margin corridor; Indicates the protection boundary; This represents the flow control coefficient when the margin is higher than the upper boundary; This represents the flow reduction control coefficient when the margin is lower than the lower boundary. This represents the margin of change rate suppression coefficient; It represents the absolute value of the rate of change of lithium intercalation capacity margin between two adjacent control cycles; Indicates the protection charging current; , , , , These represent the calibration values ​​of the target peak current, target rise slope, target recovery time, target voltage approach slope, and target termination current at the median of the margin corridor, respectively. , , , , , , , , , These represent the minimum and maximum boundary values ​​of the corresponding control variables, respectively. , , , , These represent the mapping coefficients of lithium intercalation capacity margin to the target peak current, target rise slope, target recovery time, target voltage approach slope, and target termination current, respectively.

7. A lithium battery charging chip with an adaptive charging strategy according to claim 1, characterized in that: The aging parameters in the parameter storage unit According to the The historical characteristics after the end of the second charge are updated using the following formula: Indicates the first Aging parameters after the first charge; Indicates the first Aging parameters before the start of the next charge; The aging weighting coefficient represents the decay time constant of the constant pressure wake. Indicates the first The wake decay time constant during the constant voltage stage at the end of the second charge; The aging weighting coefficient represents the temperature rise gain per unit charge. Indicates the first Temperature rise gain corresponding to the unit charge input per charge; An aging weighting coefficient representing the ratio of long window recovery to short window recovery; Indicates the first Recovery amount during the long window during the second charge; Indicates the first Short-window recovery amount during the second charge; This represents a fixed positive number to prevent the denominator from being zero. The aging weighting coefficient represents the charging time drift within the preset state of charge interval; Indicates the first The charging time drift during the second charge within the preset state of charge range; the aging parameters Used to correct the process during the next charge. , and .

8. An adaptive charging control method for a lithium battery charging chip based on an adaptive charging strategy according to any one of claims 1 to 7, characterized in that, Includes the following steps: Sp1: The input power regulation unit receives external power, and the main charging execution unit outputs the initial main charging current to the lithium battery to be charged. ; Sp2, the structured probe current fragment injection unit in the first The initial main charging current within each control cycle Superimposed structured probe current chip And form the total output current. ; Sp3, Battery Terminal Voltage Sampling Unit acquires battery terminal voltage sequence The charging current sampling unit collects the charging current sequence. The battery temperature sampling unit collects the battery temperature. The chip temperature sampling unit collects the junction temperature of the chip's power region. and the junction temperature of the chip analog region ; Sp4, the response decomposition unit from the battery terminal voltage sequence Extracting transient pressure drop Short window recovery amount Long window recovery volume , Restore the initial slope and restoration curvature ; Sp5, the dual-reservoir status observation unit, based on the transient pressure drop... Short window recovery amount Long window recovery volume , Restore the initial slope Restoring curvature Battery temperature and aging parameters Calculate the surface lithium intercalation state. and bulk lithium intercalation state quantity ; Sp6, the lithium intercalation capacity margin calculation unit is based on the surface lithium intercalation state quantity Bulk lithium intercalation state quantity Main charging current diffusion transfer coefficient Surface embedding coefficient Lithium saturation value on the negative electrode surface Chip power region junction temperature Chip analog region junction temperature and battery temperature Calculate the thermally corrected lithium intercalation capacity margin parameters ; Sp7, the margin corridor control unit is based on the thermally corrected lithium intercalation capacity margin parameters. Generate the target charging current for the next control cycle. Target peak current Target ascent slope Target recovery time Target voltage approximation slope and target termination current ; Sp8, the safety arbitration unit performs constraint trimming on the target parameters obtained in step Sp7, and drives the main charging execution unit to output the corresponding charging trajectory, and then returns to step Sp2 to enter the next control cycle.

9. The adaptive charging control method for a lithium battery charging chip with an adaptive charging strategy according to claim 8, characterized in that: After performing step Sp7, when the battery state of charge is satisfied And the thermally corrected lithium intercalation capacity margin parameter satisfies When this happens, perform the following steps: Sp9 and the margin corridor control unit switch the charging trajectory to a guided charging trajectory, which satisfies the following piecewise function: Indicates the first Battery state of charge for each control cycle; This represents the state of charge threshold for entering the high-charge state region; Indicates the first The guided charging trajectory current within each control cycle; Indicates the ramp initiation current; Indicates the ramp termination current and holding current; Indicates the duration of the uphill section of the slope; Indicates the duration of the constant value period; Indicates the duration of the restored observation segment; Indicates that within the ascending section of the slope, from linearly rising to The current increment; Sp10, the response decomposition unit re-extracts the transient voltage drop under the guided charging trajectory. Short window recovery amount Long window recovery volume , Restore the initial slope and restoration curvature The dual-liquidity state observation unit recalculates the surface lithium intercalation state quantities. and bulk lithium intercalation state quantity The lithium intercalation capacity margin calculation unit recalculates the thermally corrected lithium intercalation capacity margin parameters. ; Sp 11. When the recalculated thermally corrected lithium intercalation capacity margin parameter satisfies When the time is right, exit the guided charging trajectory and return to step Sp7; when the recalculated thermally corrected lithium intercalation capacity margin parameter satisfies If necessary, return to step Sp9 to continue executing the guided charging trajectory.

10. A method for fabricating a lithium battery charging chip based on an adaptive charging strategy according to any one of claims 1 to 7, characterized in that, Includes the following steps: Sp1, divide the semiconductor substrate into a high-voltage power region, a low-noise analog region, and a digital control region; Sp2, a deep trench isolation structure and a deep well shielding structure are formed between the high-voltage power region and the low-noise simulation region; Sp3, forming high-voltage LDMOS devices, driver devices and power metal interconnects corresponding to the input power regulation unit, main charging execution unit and structured probe current chip injection unit in the high-voltage power region; Sp4, low offset operational amplifiers, reference sources, sample-and-hold circuits, analog-to-digital converters, and analog matching resistor-capacitor arrays are formed in the low-noise analog region for the battery terminal voltage sampling unit, charging current sampling unit, battery temperature sampling unit, chip temperature sampling unit, and response decomposition unit. Sp5, in the digital control area, digital logic circuits, timing control circuits and non-volatile memory are formed corresponding to the dual-library state observation unit, lithium intercalation capacity margin calculation unit, margin corridor control unit, security arbitration unit and parameter storage unit. Sp6. A first on-chip temperature node is formed near the power switch region, and a second on-chip temperature node is formed near the analog sampling region. A fixed thermal coupling relationship is established between the first on-chip temperature node and the power switch region, and between the second on-chip temperature node and the analog sampling region, through a metal thermal diffusion path. Sp7 performs dynamic calibration on the battery terminal voltage sampling unit, charging current sampling unit, battery temperature sampling unit, chip temperature sampling unit, and response decomposition unit, and then converts the calibrated data into the final output. , , , , , , , , , , , , , , , , , , , , , and Write to the parameter storage unit; Sp8. The calibrated chip is packaged to obtain the lithium battery charging chip with the adaptive charging strategy.

Images