公开(公告)号：US20230231403A1

公开(公告)日：2023-07-20

申请号：US18189474

申请日：2023-03-24

Applicant: BYD COMPANY LIMITED

Inventor： Tianyu FENG ,  Shiwei SHU ,  Linwang DENG ,  Xiaoqian LI

IPC: H02J7/00 ,  G01R31/3835 ,  G01R31/389 ,  H01M10/44 ,  H01M10/48

CPC classification number: H02J7/00714 ,  G01R31/389 ,  G01R31/3835 ,  H01M10/44 ,  H01M10/48 ,  H02J7/0047 ,  B60R16/033 ,  H01M2220/20

Abstract: A battery charging method based on lithium plating detection includes: acquiring a battery charging strategy table after receiving a battery charging instruction; charging a battery according to a charging current in the battery charging strategy table, and performing at least one charging lithium plating detection on the battery during the charging of the battery, to obtain a first lithium plating detection result; continuing the charging of the battery according to the charging current and the charging lithium plating detection of the battery when no lithium plating phenomenon occurs, and stopping the charging lithium plating detection when the lithium plating phenomenon occurs or the charging of the battery is completed; and updating the charging current according to a preset first current reduction strategy when the lithium plating phenomenon occurs, and continuing the charging of the battery according to the updated charging current until the charging is completed.

公开(公告)号：US20240019496A1

公开(公告)日：2024-01-18

申请号：US18373821

申请日：2023-09-27

Applicant: BYD COMPANY LIMITED

Inventor： Linwang DENG ,  Tianyu FENG ,  Pengqing ZHANG ,  Xiaoqian LI

IPC: G01R31/367 ,  G01R31/392 ,  G01R31/387 ,  G01R31/374

CPC classification number: G01R31/367 ,  G01R31/392 ,  G01R31/387 ,  G01R31/374

Abstract: A method for obtaining a capacity of a power battery includes: collecting, by sensors, sample data of the power battery; dividing, by a processor, the sample data into multiple categories, each of the categories having a corresponding aging model and a feature identifier, the feature identifier identifying features of sample data of a corresponding category, and the aging model being obtained by: determining a fitting relationship in the aging model, and determining parameters in the fitting relationship according to sample data of a corresponding type of the aging model; acquiring, by the processor, battery state parameters of the power battery; selecting, by the processor, an aging model from multiple aging models according to the battery state parameters; and inputting, by the processor, the battery state parameters into the selected aging model to obtain the capacity of the power battery.

公开(公告)号：US20230236257A1

公开(公告)日：2023-07-27

申请号：US18189607

申请日：2023-03-24

Applicant: BYD COMPANY LIMITED

Inventor： Tianyu FENG ,  Linwang DENG ,  Shiwei SHU ,  Xiaoqian LI

IPC: G01R31/389 ,  G01R25/00 ,  G01R23/16 ,  H02J7/00

CPC classification number: G01R31/389 ,  G01R23/16 ,  G01R25/00 ,  H02J7/0047

Abstract: A method for generating an electrochemical impedance spectrum for a battery includes: collecting, in a discharge state of a battery, battery discharge information of the battery periodically according to a preset collection interval, where the battery discharge information includes collection time, and current information and voltage information associated with the collection time; performing Fourier transform according to the collection interval and battery discharge information, to obtain multiple frequency-based first battery signals; determining a second battery signal from the multiple first battery signals, where the second battery signal includes a voltage signal greater than or equal to a preset voltage threshold; and determining an electrochemical impedance at a corresponding frequency according to the second battery signal, and constructing an electrochemical impedance spectrum according to all the electrochemical impedance.

公开(公告)号：US20230025958A1

公开(公告)日：2023-01-26

申请号：US17780911

申请日：2020-10-23

Applicant: BYD COMPANY LIMITED

Inventor： Linwang DENG ,  Xiaoqian LI ,  Tianyu FENG ,  Sijia LIU

IPC: G01R31/374 ,  G01R31/3842 ,  G01R31/367 ,  B60R16/033 ,  H01M10/48 ,  H01M10/613 ,  H01M10/6554

Abstract: A battery internal temperature information processing method, a computer device, and a storage medium that first acquire off-line testing data for off-line testing a battery module and construct an equivalent thermal network model from the off-line testing data, determine optimal model parameters of the equivalent thermal network model based on a multi-objective function fitting method; thereafter, a first battery internal temperature estimate of the battery of the vehicle at a first moment in actual operation of the vehicle is determined, in turn, based on the acquired initial state vector values of the battery of the vehicle, first operational data at a first moment in actual operation of the vehicle, and an equivalent thermal network model including the optimal model parameters.

公开(公告)号：US20220357399A1

公开(公告)日：2022-11-10

申请号：US17764340

申请日：2020-09-25

Applicant: BYD COMPANY LIMITED

Inventor： Xiaoqian LI ,  Tianyu FENG ,  Sijia LIU ,  Yonggang YIN ,  Shiwei SHU

IPC: G01R31/367 ,  G01R31/389 ,  G01R31/382 ,  G01R31/374

Abstract: A battery temperature estimation method includes fitting, when a battery is in an offline state, a first function relationship according to corresponding admittances of the battery at different test temperatures, and obtaining a temperature distribution model of the battery according to the shape and the size of the battery, and determining a second function relationship corresponding to internal temperatures and a surface temperature by combining with the first function relationship. The second function relationship is used for estimating the internal temperature of the battery by using the surface temperature and the admittances of the battery.

公开(公告)号：US20240353499A1

公开(公告)日：2024-10-24

申请号：US18758033

申请日：2024-06-28

Applicant: BYD COMPANY LIMITED

Inventor： Xiaoqian LI ,  Tianyu FENG ,  Linwang DENG ,  Jingjing HONG

IPC: G01R31/392 ,  G01R31/3835 ,  H02J7/00

CPC classification number: G01R31/392 ,  G01R31/3835 ,  H02J7/0047

Abstract: A method for determining a battery capacity, includes: acquiring a first inflection voltage, a first inflection electric power, a second inflection voltage, and a second inflection electric power of the battery, charging the battery and recording a first charging profile of the battery; determining a target inflection point of the battery according to the first charging profile; detecting the electric power until the charging is completed, acquiring a first charged electric power of the battery when the battery is charged to a first inflection point, and acquiring a second charged electric power of the battery when the charging is completed; and when the target inflection point includes the first inflection point, calculating a current capacity of the battery according to the first inflection electric power, the first charged electric power, and the second charged electric power. The first inflection voltage is greater than the second inflection voltage.

公开(公告)号：US20230112978A1

公开(公告)日：2023-04-13

申请号：US18080168

申请日：2022-12-13

Applicant: BYD COMPANY LIMITED

Inventor： Linwang DENG ,  Xiaoqian LI ,  Tianyu FENG ,  Sijia LIU

IPC: G01R31/392 ,  G01R19/165 ,  G01R31/3835 ,  G01R31/367

Abstract: A method for calculating a cell state includes: acquiring a first knee-point voltage threshold of a cell, a first knee-point electricity corresponding to the first knee-point voltage threshold, a second knee-point voltage threshold of the cell and a second knee-point electricity corresponding to the second knee-point voltage threshold; recording a first charging curve of the cell in real time; obtaining a target knee point according to the first charging curve, the first knee-point voltage threshold, and the second knee-point voltage threshold, and obtaining a target-knee-point electricity according to the first knee-point electricity or the second knee-point electricity; detecting the electricity of the cell until the charging is completed, and obtaining a charged electricity of the cell from the target knee point to the completion of charging; and obtaining the capacity of the cell according to the target-knee-point electricity and the charged electricity.

公开(公告)号：US20240300379A1

公开(公告)日：2024-09-12

申请号：US18669524

申请日：2024-05-21

Applicant: BYD COMPANY LIMITED

Inventor： Linwang DENG ,  Xiaoqian LI ,  Tianyu FENG ,  Jingjing HONG

IPC: B60L58/14 ,  H01M10/42 ,  H02J7/00

CPC classification number: B60L58/14 ,  H01M10/425 ,  H02J7/0047 ,  H02J7/00712 ,  H01M2010/4271 ,  H01M2220/20

Abstract: A battery management method includes: obtaining a current high-voltage inflection point power value of each cell; obtaining a current historical cumulative balance power value of each cell; obtaining a current equivalent self-discharge value of each cell through calculation; obtaining an equivalent self-discharge value at a previous moment of each cell; obtaining a target equivalent self-discharge value of each cell through calculation; determining a maximum target equivalent self-discharge value and a minimum target equivalent self-discharge value; obtaining a maximum equivalent self-discharge rate and a minimum equivalent self-discharge rate through calculation; and when a difference between the maximum equivalent self-discharge rate and the minimum equivalent self-discharge rate is greater than a preset threshold, managing a target cell corresponding to the maximum target equivalent self-discharge value.

公开(公告)号：US20230341472A1

公开(公告)日：2023-10-26

申请号：US18344556

申请日：2023-06-29

Applicant: BYD COMPANY LIMITED

Inventor： Tianyu FENG ,  Xiaoqian LI ,  Linwang DENG

IPC: G01R31/396 ,  G01R31/3842 ,  G01R31/367 ,  H02J7/00

CPC classification number: G01R31/396 ,  G01R31/3842 ,  G01R31/367 ,  H02J7/0048

Abstract: A method for determining a voltage inflection point of a cell core in a LFP battery includes: charging the LFP battery with a first current value and monitoring the State of charge (SOC) of the LFP battery, the first current value being greater than a predetermined threshold of current; if the SOC of the LFP battery is outside a predetermined detection range, charging the LFP battery with the first current value; if the SOC of the LFP battery is within the detection range, charging the LFP battery with a second current value, the second current value being less than the predetermined threshold of current; and detecting the voltage inflection point of various cell cores in the LFP battery according to parameter information of the various cell cores in the LFP battery in the process of charging where the SOC is within the detection range.

公开(公告)号：US20230152380A1

公开(公告)日：2023-05-18

申请号：US17915308

申请日：2021-03-15

Applicant: BYD COMPANY LIMITED

Inventor： Sijia LIU ,  Tianyu FENG ,  Linwang DENG ,  Xiaoqian LI ,  Xun SONG

IPC: G01R31/3842 ,  G01R31/367 ,  G01R31/36 ,  G01R31/396

CPC classification number: G01R31/3842 ,  G01R31/367 ,  G01R31/3648 ,  G01R31/396 ,  H01M2010/4271

Abstract: The present disclosure relates to a method and apparatus for determining a state of charge (SOC) of a battery and a battery management system (BMS), so as to resolve a problem such as inaccurate estimation of the SOC. The method includes: acquiring state data of the battery, where the state data comprises current data and voltage data; determining each element parameter value in an equivalent circuit model of the battery based on the equivalent circuit model, error information, battery characteristic data, and the state data by using a recursive least square (RLS) prediction model; and determining an estimated value of the SOC of the battery based on the element parameter value in the equivalent circuit model, the state data, and the battery characteristic data according to a technique of an observer.