# US 12,015,296 B2 · Charging method and apparatus

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 12,015,296 B2
- Document ID: US12015296B2
- Status: Granted
- Kind: B2
- Application number: 17/342,878
- Filed: 2021-06-09
- Published: 2021-09-23
- Granted: 2024-06-18
- Earliest claimed: 2018-12-10
- Assignees: Huawei Technologies Co., Ltd.
- Applicants: Huawei Technologies Co., Ltd.
- Inventors: Peng Lu; Xiaohu He; Jun Wu
- Web page: https://patentgrep.com/patent/US12015296B2

## CPC

- H01M 10/46: Accumulators structurally combined with charging apparatus (circuits for charging H02J7/00)
- H02J 7/825: {Detection of fully charged condition}
- B60L 53/62: in response to charging parameters, e.g. current, voltage or electrical charge
- H01M 10/425: {Structural combination with electronic components, e.g. electronic circuits integrated to the outside of the casing (printed circuits H05K1/00)}
- H01M 10/44: Methods for charging or discharging (circuits for charging H02J7/00)
- H02J 7/60: including safety or protection arrangements
- H02J 7/82: Control of state of charge [SOC]
- H02J 7/92: with prioritisation of loads or sources
- H02J 7/94: in response to battery current
- H02J 7/96: in response to battery voltage
- H01M 2010/4271: {Battery management systems including electronic circuits, e.g. control of current or voltage to keep battery in healthy state, cell balancing}
- Y02E 60/10: Energy storage using batteries
- H01M: PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H02J: ELECTRIC POWER NETWORKS; CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- B60L: PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES (arrangements or mounting of electrical propulsion units or of plural diverse prime-movers for mutual or common propulsion in vehicles B60K1/00, B60K6/20; arrangements or mounting of electrical gearing in vehicles B60K17/12, B60K17/14; preventing wheel slip by reducing power in rail vehicles B61C15/08; dynamo-electric machines H02K; control or regulation of electric motors H02P); SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES (electric coupling devices combined with mechanical couplings of vehicles B60D1/64; electric heating for vehicles B60H1/00); ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL (control or regulation of electric motors H02P); MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
- Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION

## Abstract

A charging method, where in a process of performing constant voltage charging on a battery at a charging voltage that is greater than an end-of-precharge voltage and less than a maximum charging voltage, a charging apparatus determines a current relaxation time and controls a charging current and a charging voltage based on the current relaxation time, to adaptively charge the battery.

## Claims

### Claim 1

A method comprising:
performing first constant voltage charging on a battery at a present charging voltage, wherein the present charging voltage is greater than an end-of-precharge voltage of the battery and less than a maximum charging voltage of the battery, wherein the maximum charging voltage represents a withstand voltage of a positive electrode material, an electrolyte, or a positive electrode current collector of the battery, and wherein the end-of-precharge voltage is a critical voltage at which the battery changes from an overdischarge state to a normal discharge state;
determining a current relaxation time while performing the first constant voltage charging on the battery, wherein the current relaxation time reflects a change of an electrochemical reaction rate in the battery;
obtaining a present state of charge (SOC) of the battery;
calculating a would-be charging current based on the current relaxation time and the present SOC; and
performing at least one of:
performing constant current charging on the battery at the would-be charging current, determining a first voltage of a first preset threshold as a would-be charging voltage and performing a second constant voltage charging on the battery at the would-be charging voltage when a second voltage of the battery reaches the first preset threshold while performing the constant current charging, and performing a third constant voltage charging on the battery at the maximum charging voltage until a quantity of electricity in the battery reaches a full-charge quantity of electricity when the second voltage reaches the maximum charging voltage while performing the constant current charging, wherein the first voltage is less than the maximum charging voltage, and wherein the battery reaches the full-charge quantity of electricity when the battery is fully charged; or
determining a third voltage corresponding to the would-be charging current as the would-be charging voltage, performing the second constant voltage charging on the battery, repeating each of performing the first constant voltage charging on the battery, determining the current relaxation time, obtaining the present SOC, and calculating the would-be charging current, during a constant voltage charging process until the would-be charging voltage reaches the maximum charging voltage, and performing the third constant voltage charging on the battery until the quantity of electricity reaches the full-charge quantity of electricity.

### Claim 2 (depends on 1)

The charging method of claim 1, further comprising:
determining a first moment when a peak value of a charging current occurs while performing the first constant voltage charging on the battery;
determining a second moment when a value of the charging current is a second preset threshold or a change rate of the charging current is less than a preset change rate while performing the first constant voltage charging on the battery, wherein the first moment is earlier than the second moment; and
further determining the current relaxation time based on the first moment and the second moment.

### Claim 3 (depends on 1)

The charging method of claim 1, further comprising further calculating the would-be charging current according to a formula, wherein the formula is:
I=C+K×τM(SOC),
wherein I represents the would-be charging current, wherein τ represents the current relaxation time, wherein SOC in the formula represents the present SOC of the battery, wherein K is a proportionality coefficient, wherein C is a constant greater than or equal to zero, wherein M is an exponent coefficient, wherein M≠0, wherein a charging parameter comprises at least one of C, K, or M, wherein the charging parameter is either preset or is set based on a battery parameter, and wherein the battery parameter comprises at least one of the present SOC of the battery, a present state of health (SOH) of the battery, the current relaxation time, a present temperature of the battery, or a present state of safety (SOS) of the battery.

### Claim 4 (depends on 2)

The method of claim 2, further comprising further calculating the would-be charging current according to a formula, wherein the formula is:
I=C+K×τM(SOC),
wherein I represents the would-be charging current, wherein τ represents the current relaxation time, wherein SOC in the formula represents the present SOC of the battery, wherein K is a proportionality coefficient, wherein C is a constant greater than or equal to zero, wherein M is an exponent coefficient, wherein M≠0, wherein a charging parameter comprises at least one of C, K, or M, wherein the charging parameter is either preset or is set based on a battery parameter, and wherein the battery parameter comprises at least one of the present SOC of the battery, a present state of health (SOH) of the battery, the current relaxation time, a present temperature of the battery, or a present state of safety (SOS) of the battery.

### Claim 5 (depends on 3)

The method of claim 3, further comprising:
setting the charging parameter based on the battery parameter; and
adjusting, in response to the setting the charging parameter, the charging parameter based on the battery parameter.

### Claim 6 (depends on 4)

The method of claim 4, further comprising:
setting the charging parameter based on the battery parameter; and
adjusting, in response to the setting the charging parameter, the charging parameter based on the battery parameter.

### Claim 7

A charging apparatus, comprising:
a memory configured to store instructions; and
a processor coupled to the memory and configured to:
to perform first constant voltage charging on a battery at a present charging voltage, wherein the present charging voltage is greater than an end-of-precharge voltage of the battery and less than a maximum charging voltage of the battery, wherein the maximum charging voltage represents a withstand voltage of a positive electrode material, an electrolyte, or a positive electrode current collector of the battery, and wherein the end-of-precharge voltage is a critical voltage at which the battery changes from an overdischarge state to a normal discharge state;
determine a current relaxation time while to performing the first constant voltage charging on the battery, wherein the current relaxation time reflects a change of an electrochemical reaction rate in the battery;
obtain the present state of charge (SOC) of the battery;
calculate a would-be charging current based on the current relaxation time and the present SOC; and
perform at least one of:
perform constant current charging on the battery at the would-be charging current, determine a first voltage of a first preset threshold as a would-be charging voltage and perform a second constant voltage charging on the battery at the would-be charging voltage when a second voltage of the battery reaches the first preset threshold while performing the constant current charging, and perform a third constant voltage charging on the battery at the maximum charging voltage until a quantity of electricity in the battery reaches a full-charge quantity of electricity when the second voltage reaches the maximum charging voltage while performing the constant current charging, wherein the first voltage is less than the maximum charging voltage, and wherein the battery reaches the full-charge quantity of electricity when the battery is fully charged; or
determine a third voltage corresponding to the would-be charging current as the would-be charging voltage, to perform the second constant voltage charging on the battery, repeat each of performing the first constant voltage charging on the battery, determining the current relaxation time, obtaining the present SOC, and calculating the would-be charging current, during a constant voltage charging process until the would-be charging voltage reaches the maximum charging voltage, and to perform the third constant voltage charging on the battery until the quantity of electricity reaches the full-charge quantity of electricity.

### Claim 8 (depends on 7)

The charging apparatus of claim 7, wherein the processor is further configured to:
determine a first moment when a peak value of a charging current occurs while performing the first constant voltage charging on the battery;
determine a second moment when a value of the charging current is a second preset threshold or a change rate of the charging current is less than a preset change rate while performing the first constant voltage charging on the battery, wherein the first moment is earlier than the second moment; and
further determine the current relaxation time based on the first moment and the second moment.

### Claim 9 (depends on 7)

The charging apparatus of claim 7, wherein the processor is further configured to further calculate the would-be charging current according to a formula, and wherein the formula is:
I=C+K×τM(SOC),
wherein I represents the would-be charging current, wherein τ represents the current relaxation time, wherein SOC in the formula represents the present SOC of the battery, wherein K is a proportionality coefficient, wherein C is a constant greater than or equal to zero, wherein M is an exponent coefficient, wherein M≠0, wherein a charging parameter comprises at least one of C, K, or M, wherein the charging parameter is either preset or is set based on a battery parameter, and wherein the battery parameter comprises at least one of the present SOC of the battery, a present state of health (SOH) of the battery, the current relaxation time, a present temperature of the battery, or a present state of safety (SOS) of the battery.

### Claim 10 (depends on 8)

The charging apparatus of claim 8, wherein the processor is further configured to further calculate the would-be charging current according to a formula, wherein the formula is:
I=C+K×τM(SOC),
wherein I represents the would-be charging current, wherein τ represents the current relaxation time, wherein SOC in the formula represents the present SOC of the battery, wherein K is a proportionality coefficient, wherein C is a constant greater than or equal to zero, wherein M is an exponent coefficient, wherein M≠0, wherein a charging parameter comprises at least one of C, K, or M, wherein the charging parameter is either preset or is set based on a battery parameter, and wherein the battery parameter comprises at least one of the present SOC of the battery, a present state of health (SOH) of the battery, the current relaxation time, a present temperature of the battery, or a present state of safety (SOS) of the battery.

### Claim 11 (depends on 9)

The charging apparatus of claim 9, wherein the processor is further configured to:
set the charging parameter based on the battery parameter; and
adjust, in response to the setting the charging parameter, the charging parameter based on the battery parameter.

### Claim 12 (depends on 10)

The charging apparatus of claim 10, wherein the processor is further configured to:
set the charging parameter based on the battery parameter; and
adjust, in response to the setting the charging parameter, the charging parameter based on the battery parameter.

### Claim 13

A computer program product comprising computer-executable instructions stored on a non-transitory computer-readable medium that, when executed by a processor, cause a charging apparatus to:
perform first constant voltage charging on a battery at a present charging voltage, wherein the present charging voltage is greater than an end-of-precharge voltage of the battery and less than a maximum charging voltage of the battery, wherein the maximum charging voltage represents a withstand voltage of a positive electrode material, an electrolyte, or a positive electrode current collector of the battery, and wherein the end-of-precharge voltage is a critical voltage at which the battery changes from an overdischarge state to a normal discharge state;
determine a current relaxation time while performing the first constant voltage charging on the battery, wherein the current relaxation time reflects a change of an electrochemical reaction rate in the battery;
obtain a present state of charge (SOC) of the battery;
calculate a would-be charging current based on the current relaxation time and the present SOC; and
perform at least one of:
perform constant current charging on the battery at the would-be charging current, determine a first voltage of a first preset threshold as a would-be charging voltage and perform a second constant voltage charging on the battery at the would-be charging voltage when a second voltage of the battery reaches the first preset threshold during the constant current charging, and perform a third constant voltage charging on the battery at the maximum charging voltage until a quantity of electricity in the battery reaches a full-charge quantity of electricity when the second voltage reaches the maximum charging voltage during the constant current charging, wherein the first voltage is less than the maximum charging voltage, and wherein the battery reaches the full-charge quantity of electricity when the battery is fully charged; or
determine a third voltage corresponding to the would-be charging current as the would-be charging voltage, perform the second constant voltage charging on the battery, repeat each of performing the first constant voltage charging on the battery, determining the current relaxation time, obtaining the present SOC, and calculating the would-be charging current, during a constant voltage charging process until the would-be charging voltage reaches the maximum charging voltage, and perform the third constant voltage charging on the battery until the quantity of electricity reaches the full-charge quantity of electricity.

### Claim 14 (depends on 13)

The computer program product of claim 13, wherein the computer-executable instructions further cause the charging apparatus to:
determine a first moment when a peak value of a charging current occurs while performing the first constant voltage charging on the battery;
determine a second moment when a value of the charging current is a second preset threshold or a change rate of the charging current is less than a preset change rate while performing the first constant voltage charging on the battery, wherein the first moment is earlier than the second moment; and
further determine the current relaxation time based on the first moment and the second moment.

### Claim 15 (depends on 13)

The computer program product of claim 13, wherein the computer-executable instructions further cause the charging apparatus to further calculate the would-be charging current according to a formula, and wherein the formula is:
I=C+K×τM(SOC),
wherein I represents the would-be charging current, wherein τ represents the current relaxation time, wherein SOC in the formula represents the present SOC of the battery, wherein K is a proportionality coefficient, wherein C is a constant greater than or equal to zero, wherein M is an exponent coefficient, wherein M≠0, wherein a charging parameter comprises at least one of C, K, M, wherein the charging parameter is either preset or is set based on a battery parameter, and wherein the battery parameter comprises at least one of the present SOC of the battery, a present state of health (SOH) of the battery, the current relaxation time, a present temperature of the battery, or a present state of safety (SOS) of the battery.

### Claim 16 (depends on 14)

The computer program product of claim 14, wherein the computer-executable instructions further cause the charging apparatus to further calculate the would-be charging current according to a formula, and wherein the formula is:
I=C+K×τM(SOC),
wherein I represents the would-be charging current, wherein τ represents the current relaxation time, wherein SOC in the formula represents the present SOC of the battery, wherein K is a proportionality coefficient, wherein C is a constant greater than or equal to zero, wherein M is an exponent coefficient, wherein M≠0, wherein a charging parameter comprises at least one of C, K, or M, wherein the charging parameter is either preset or is set based on a battery parameter, and wherein the battery parameter comprises at least one of the present SOC of the battery, a present state of health (SOH) of the battery, the current relaxation time, a present temperature of the battery, or a present state of safety (SOS) of the battery.

### Claim 17 (depends on 15)

The computer program product of claim 15, wherein the computer-executable instructions further cause the charging apparatus to set the charging parameter based on the battery parameter.

### Claim 18 (depends on 16)

The computer program product of claim 16, wherein the computer-executable instructions further cause the charging apparatus to set the charging parameter based on the battery parameter.

### Claim 19 (depends on 18)

The computer program product of claim 18, wherein the computer-executable instructions further cause the charging apparatus to adjust, in response to the setting the charging parameter, the charging parameter based on the battery parameter.

### Claim 20 (depends on 17)

The computer program product of claim 17, wherein the computer-executable instructions further cause the charging apparatus to adjust, in response to the setting the charging parameter, the charging parameter based on the battery parameter.