Sop management method and apparatus for power battery pack, and electric vehicle

Patent metadata

Field	Value
Publication number	US-2024149742-A1
Application number	US-202118275023-A
Country	US
Kind code	A1
Filing date	Feb 1, 2021
Priority date	Feb 1, 2021
Publication date	May 9, 2024
Grant date	—

Abstract

Provided are an SOP management method and apparatus for a power battery pack, and an electric vehicle. The SOP management method includes: obtaining a SOP value of each parallel battery branch in a power battery pack; and obtaining a current total SOP value of the power battery pack according to the SOP value of each parallel battery branch. In the present application, in a multi-branch-parallel power battery pack, an SOP value of each parallel branch is first subjected to refined estimation according to an operation condition of each parallel branch, and then the total SOP of the power battery pack is estimated from the whole system level, and the problem of statistical distortion of the total SOP of the power battery pack is solved, thereby effectively improving the safety and stability of use of the battery.

First claim

1 . An SOP management method for a power battery pack, comprising the following steps:
obtaining an SOP value of each parallel battery branch in the power battery pack; obtaining a current total SOP value of the power battery pack according to the SOP value of each parallel battery branch.

2 . The SOP management method for the power battery pack as claimed in 1 , wherein the step of obtaining the SOP value of each parallel battery branch in the power battery pack comprises:
obtaining an operating condition of the each parallel battery branch; obtaining the SOP value of the each parallel battery branch according to the operating condition and a corresponding SOP value reference table.

3 . The SOP management method for the power battery pack as claimed in 2 , wherein the step of obtaining the SOP value of the each parallel battery branch according to the operating condition and the corresponding SOP value reference table comprises:
obtaining an initial SOP value of the each parallel battery branch according to the operating condition and the corresponding SOP value reference table; obtaining a fault level of each parallel battery branch; performing power limiting processing on the initial SOP value of the each parallel battery branch according to the fault level of the each parallel battery branch, so as to obtain the SOP value of the each parallel battery branch.

4 . The SOP management method for the power battery pack as claimed in 3 , wherein the step of obtaining the fault level of the each parallel battery branch comprises:
obtaining a battery temperature and a battery voltage of the each parallel battery branch; obtaining the fault level of the each parallel battery branch according to the battery temperature and the battery voltage of the each parallel battery branch.

5 . The SOP management method for the power battery pack according to claim 1 , wherein the step of obtaining the current total SOP value of the power battery pack according to the SOP value of the each parallel battery branch comprises:
obtaining the minimum value in the SOP value of the each parallel battery branch; obtaining the current total SOP value of the power battery pack according to the minimum value of the SOP value of the each parallel battery branch and number of the parallel branches in the power battery pack.

6 . The SOP management method for the power battery pack as claimed in 5 , wherein after the step of obtaining the current total SOP value of the power battery pack according to the minimum value of the SOP value of the each parallel battery branch and the number of the parallel branches in the power battery pack, the method further comprises:
determining whether the power battery pack has a parallel battery branch with serious faults; when there is a parallel battery branch with serious faults in the power battery pack, disconnecting the parallel battery branch with serious faults, and controlling the remaining parallel battery branches to output a preset total SOP value.

7 . The SOP management method for the power battery pack as claimed in 5 , wherein the step of obtaining the current total SOP value of the power battery pack according to the minimum value of the SOP value of the each parallel battery branch and the number of the parallel branches in the power battery pack comprises:
obtaining a first target total SOP value of the power battery pack through multiplying the minimum SOP value of the each parallel battery branch and the number of the parallel branches of the power battery pack; obtaining the current total SOP value of the power battery pack through filtering a last total SOP value of the power battery pack according to the first target total SOP value of the power battery pack.

8 . The SOP management method for the power battery pack as claimed in 7 , wherein a filtering process formula of filtering the last total SOP value of the power battery pack according to the first target total SOP value of the power battery pack is:
Z=δ*Z 0 +(1−δ)* Z 1
wherein, Z is the current total SOP value of the power battery pack, Z 0 is a current first target total SOP value of the power battery pack, Z 1 is the last total SOP value of the power battery pack, and δ is a preset coefficient.

9 . The SOP management method for the power battery pack as claimed in 5 , wherein after the step of obtaining the current total SOP value of the power battery pack according to the minimum value of the SOP value of the each parallel battery branch and the number of the parallel branches in the power battery pack, the method further comprises:
outputting the current total SOP value of the power battery pack; determining whether accumulated time is greater than a preset value; when the accumulated time is greater than the preset value, determining whether the power battery pack has a parallel battery branch with serious faults; when there is a parallel battery branch with serious faults in the power battery pack, disconnecting the parallel battery branch with serious faults, and controlling remaining parallel battery branches to output a preset total SOP value.

10 . The SOP management method for the power battery pack as claimed in 6 , wherein the SOP management method for the power battery pack further comprises:
obtaining a fault level of the power battery pack when there is no parallel battery branch with serious faults in the power battery pack; obtaining a second target total SOP value according to the minimum value of SOP values of online parallel battery branches and number of the online parallel battery branches; performing power limiting processing on the second target total SOP value according to the fault level of the power battery pack to obtain an updated second target total SOP value; performing a corresponding filtering process on a last total SOP value of the power battery pack according to the updated second target total SOP value, to obtain the current total SOP value of the power battery pack.

11 . The SOP management method for the power battery pack as claimed in 1 , wherein the SOP management method for the power battery pack further comprises:
obtaining a real-time charge and discharge current of the each parallel battery branch in the power battery pack; adjusting the output of the parallel battery branch to the current SOP value of the branch, when the real-time charge and discharge current of one of the parallel battery branches is in an abnormal state, wherein the abnormal state comprises that time period, during which the real-time charge and discharge current is greater than the SOP value of the branch under current parameter condition, reaches a first time value; or comprises that time period, during which the real-time charge and discharge current is less than a preset ratio of the SOP value of the branch under the current parameter condition, reaches a second time value.

12 . An SOP management apparatus for a power battery pack, wherein the apparatus comprises a primary battery management unit and a plurality of secondary battery management units, the primary battery management unit and the plurality of secondary battery management units are connected in communication, wherein,
each secondary battery management unit is configured to obtain an SOP value of the corresponding parallel battery branch in the power battery pack and send it to the primary battery management unit; the primary battery management unit is configured to obtain a current total SOP value of the power battery pack according to the SOP value of each parallel battery branch.

13 . An electric vehicle, comprising the SOP management

Assignees

• Microvast Power Systems Co Ltd
• Microvast Inc

Inventors

• Yao Zhenfei
• Wu Shengxian
• Zhang Ruijing
• Xu Wenhao

Classifications

• H02J7/663

  using battery or load disconnect circuits (H02J9/002 takes precedence) · CPC title

• H02J7/94 Primary

  in response to battery current · CPC title

• H02J7/82

  Control of state of charge [SOC] · CPC title

• H02J7/62

  against overcurrent · CPC title

• B60L58/21

  having the same nominal voltage · CPC title