公开(公告)号：US20230093420A1

公开(公告)日：2023-03-23

申请号：US17994730

申请日：2022-11-28

Applicant: BYD COMPANY LIMITED

Inventor： Linwang DENG ,  Yonggang YIN ,  Tianyu FENG ,  Sijia LIU

IPC: G01R31/3835 ,  G01K1/14 ,  G01K3/00 ,  H01M10/48

Abstract: A warning method for battery thermal runaway includes: acquiring current temperature data of each temperature sensor arranged in a battery pack, current voltage data of each voltage sensor arranged in the battery pack, and current sensor disconnection data of each temperature sensor; calculating a number of occurrences of a primary feature at a current moment according to the current temperature data; calculating a number of occurrences of a secondary feature at the current moment according to the current voltage data and the current sensor disconnection data in a case that the number of occurrences of the primary feature is greater than 0; calculating a sum of the number of occurrences of the primary feature and the number of occurrences of the secondary feature at the current moment; and sending a warning for battery thermal runaway when the sum is greater than a preset feature number threshold.

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：US20230221373A1

公开(公告)日：2023-07-13

申请号：US18188788

申请日：2023-03-23

Applicant: BYD COMPANY LIMITED

Inventor： Linwang DENG ,  Tianyu FENG ,  Shiwei SHU ,  Sijia LIU

IPC: G01R31/3835 ,  G01R31/371

CPC classification number: G01R31/3835 ,  G01R31/371

Abstract: A method for detecting a lithium plating state of a battery includes regularly collecting a voltage of a battery after the end of charging at a preset time interval after the battery is in an idle state, and associatively storing the collected voltage and a collection time as voltage data; constructing a time-differential voltage curve in a voltage-time coordinate system according to the voltage data; detecting whether a characteristic peak voltage exists in the time-differential voltage curve; and sending a warning message when detecting that the characteristic peak voltage exists in the time-differential voltage curve.

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.

公开(公告)号：US20220352728A1

公开(公告)日：2022-11-03

申请号：US17763943

申请日：2020-09-24

Applicant: BYD COMPANY LIMITED

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

IPC: H02J7/00 ,  B60R16/033 ,  H01M10/48 ,  H01M10/44

Abstract: A step-varying equalization method, a device, a medium, a battery pack, and a vehicle are provided. The method includes: initiating coarse-tuning equalization for a cell in the series-connected battery when an initial equalization difference of the cell reaches a preset coarse-tuning requirement; determining a first state of charge (SOC) equalization difference according to a first voltage value of the cell after completion of the coarse-tuning equalization when a first real equalization difference of the cell after the coarse-tuning equalization reaches a preset fine-tuning requirement, and initiating fine-tuning equalization for the cell with a first equalization step size based on the first SOC equalization difference; and determining that SOC equalization of the cell is completed when a second real equalization difference of the cell after completion of the fine-tuning equalization is less than or equal to a target equalization value.

公开(公告)号：US20230168097A1

公开(公告)日：2023-06-01

申请号：US18154564

申请日：2023-01-13

Applicant: BYD COMPANY LIMITED

Inventor： Linwang DENG ,  Guanhao DU ,  Tianyu FENG ,  Sijia LIU

IPC: G01C21/34 ,  G01C21/36

CPC classification number: G01C21/3469 ,  G01C21/3461 ,  G01C21/3492 ,  G01C21/3682

Abstract: A path determination method includes: obtaining current position information and destination position information of a target vehicle; determining a candidate path of the target vehicle according to the current position information and the destination position information; acquiring road condition information of the candidate path and reference vehicle information; determining first energy consumption information required to be consumed by the target vehicle to travel on the candidate path over a unit distance according to the road condition information and the reference vehicle information; and recommending the candidate path to the target vehicle according to the first energy consumption information.

公开(公告)号：US20230093620A1

公开(公告)日：2023-03-23

申请号：US17994694

申请日：2022-11-28

Applicant: BYD COMPANY LIMITED

Inventor： Long HE ,  Linwang DENG ,  Tianyu FENG ,  Sijia LIU

IPC: B60L58/27

Abstract: A power battery heating method for an electric vehicle includes: acquiring a heating power demand of a power battery; acquiring power demand information of a driving module of the electric vehicle in real time, and determining a current heating power of the power battery according to the power demand information; acquiring a compensating heating current according to the heating power demand and the current heating power when the current heating power is less than the heating power demand; causing the motor controller to regulate a control current of the driving motor according to the compensating heating current, so that the driving motor outputs a high-frequency oscillation current equal to the compensating heating current; and causing the power battery to perform self-heating according to the high-frequency oscillation current outputted by the driving motor.

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.