CN-122000503-A - Electrochemical impedance spectroscopy systems and methods

CN122000503ACN 122000503 ACN122000503 ACN 122000503ACN-122000503-A

Abstract

Electrochemical impedance spectroscopy systems and methods. An electrochemical impedance system includes a vehicle battery, a Battery Management System (BMS), an excitation power module, and a current sensor. The vehicle battery in turn includes one, two or more battery modules. Each battery module includes a plurality of battery cells. The BMS is configured to control the excitation power supply module to excite at least the one, two, or more battery modules. The current sensor is configured to sense a current of at least the one, two, or more battery modules. The BMS is further configured to sense, determine, or receive voltages of the plurality of battery cells of the one, two, or more battery modules, and also receive currents of the one, two, or more battery modules sensed by the current sensor. In this way, the system of the present disclosure is able to determine the electrochemical impedance of the vehicle battery. A corresponding method is also provided.

Inventors

R. Bautista Florence
A. Gomez Nunez

Assignees

法可赛汽车有限公司

Dates

Publication Date: 20260508
Application Date: 20251126
Priority Date: 20241106

Claims (15)

1. An electrochemical impedance spectroscopy system, the electrochemical impedance spectroscopy system comprising: -a vehicle battery (10) comprising one, two or more battery modules (M1, M2), wherein each battery module (M1, M2) comprises a plurality of battery cells (C1, C2, C3); -a battery management system (20) electrically connected to the vehicle battery (10), wherein the battery management system (20) is configured to sense, determine or receive voltages (V1, V2, V3) of the plurality of battery cells (C1, C2, C3) of the one, two or more battery modules (M1, M2), wherein the battery management system (20) is configured to control the vehicle battery (10); -an excitation power module (30) electrically connected to the vehicle battery (10) and the battery management system (20), wherein the excitation power module (30) is configured to excite at least the one, two or more battery modules (M1, M2), and A current sensor (40) configured to sense a current (I) of at least the one, two or more battery modules (M1, M2) when energized, Wherein the battery management system (20) is configured to receive the current (I) of the one, two or more battery modules (M1, M2) sensed by the current sensor (40), and Wherein the battery management system (20) is configured to determine the impedance (Z1, Z2, Z3) of the plurality of battery cells (C1, C2, C3) of the one, two or more battery modules (M1, M2) based at least on the current (I) and the voltage (V1, V2, V3), or Wherein the battery management system (20) is configured to send the current (I) and the voltage (V1, V2, V3) to an external controller (200) configured to determine the impedance (Z1, Z2, Z3) of the plurality of battery cells (C1, C2, C3) of the one, two or more battery modules (M1, M2) based at least on the current (I) and the voltage (V1, V2, V3).
2. The system of claim 1, wherein the current sensor (40) is a single current sensor electrically connected to two or more battery modules (M1, M2), wherein the current sensor (40) is configured to sense current of at least the two or more battery modules (M1, M2).
3. The system of claims 1 to 2, wherein the excitation power supply module (30) is a single excitation power supply module, wherein the excitation power supply module (30) is configured to excite at least two or more battery modules (M1, M2).
4. A system according to claims 1 to 3, wherein the excitation power supply module (30) is arranged outside the vehicle battery (10) and the battery management system (20).
5. The system of claims 1 to 4, wherein the current sensor (40) is electrically disposed between the excitation power module (30) and the vehicle battery (10), including electrically disposed in the excitation power module (30), electrically disposed in the vehicle battery (10), or electrically disposed in a junction box (300).
6. The system of claims 1 to 5, wherein the battery management system (20) is configured to receive a Vehicle Input Signal (VIS), wherein the Vehicle Input Signal (VIS) is related to at least a vehicle state and a vehicle battery state, and wherein the battery management system (20) is configured to determine a trigger command of the system based at least on the Vehicle Input Signal (VIS).
7. The system of claim 6, wherein the vehicle state is at least one of park mode, ignition off, vehicle not activated, and wherein the vehicle battery state includes whether the vehicle battery receives and/or supplies power.
8. The system of claims 6 to 7, wherein the battery management system (20) is further configured to receive or generate a start-up instruction, wherein the trigger command of the system is further based on the start-up instruction, preferably the start-up instruction is based on at least one of: -a pre-defined time period for which, -A predefined distance, and -Instructions from the user or driver.
9. The system according to claims 6 to 8, wherein the triggering command of the system is further based on the temperature of the vehicle battery (10) and/or a preset time, preferably the triggering command is delayed for the preset time or until the temperature of the vehicle battery (10) is below a preset temperature.
10. The system according to claims 6 to 9, wherein the Vehicle Input Signal (VIS) is received from a Vehicle Control Unit (VCU) or via a vehicle bus communication channel, wherein the Vehicle Control Unit (VCU) is arranged outside the system.
11. The system of claims 6 to 10, wherein the battery management system (20) or the external controller is configured to receive the vehicle battery state or a change in the vehicle state, and wherein the battery management system (20) or the external controller is configured to stop determining the impedance (Z1, Z2, Z3) based on the vehicle battery state or the change in the vehicle state.
12. The system according to claims 6 to 11, wherein the triggering command of the system is further based on a cell balancing of the vehicle battery (10), preferably the triggering command is delayed until the cell balancing is completed.
13. A method of operating an electrochemical impedance spectroscopy system, the method comprising: -providing a vehicle battery (10) comprising a first battery module (M1) comprising a plurality of battery cells (C1, C2, C3); -electrically connecting a battery management system (20) to the vehicle battery (10); -forming an electrical circuit by electrically connecting at least the first module (M1) and an excitation power supply module (30); -electrically connecting the excitation power supply module (30) to the battery management system (20); -electrically connecting a current sensor (40) to the circuit; -powering the excitation power supply module (30) configured to excite the circuit; -sensing a current (I) of the circuit by means of the current sensor (40) at least when the circuit is excited; -receiving, by the battery management system (20), the current (I) of the circuit sensed by the current sensor (40); -sensing, determining or receiving the voltages (V1, V2, V3) of the plurality of battery cells (C1, C2, C3) of the first battery module (M1) by the battery management system (20), and -Determining, by the battery management system (20), the impedance (Z1, Z2, Z3) of the plurality of battery cells (C1, C2, C3) of the first battery module (M1) based at least on the current (I) and the voltage (V1, V2, V3), or -Sending the current (I) and the voltage (V1, V2, V3) to an external controller configured to determine the impedance (Z1, Z2, Z3) of the plurality of battery cells (C1, C2, C3) of the one, two or more battery modules (M1, M2) based at least on the current (I) and the voltage (V1, V2, V3).
14. The method of claim 13, wherein the method further comprises: -providing the vehicle battery (10) with a second battery module (M2), the second battery module (M2) comprising a plurality of battery cells (C1 ', C2', C3 '); -electrically connecting the second module (M2) to the circuit; -sensing or determining by the battery management system (20) voltages (V1, V2, V3, V1', V2', V3 ') of the plurality of battery cells (C1, C2, C3, C1', C2', C3') of the first battery module (M1) and the second battery module (M2), and -Determining, by the battery management system (20), the impedance (Z1, Z2, Z3, Z1', Z2', Z3 ') of the plurality of battery cells (C1, C2, C3, C1', C2', C3 ') of the first battery module (M1) and the second battery module (M2) based at least on the current (I) and the voltage (V1, V2, V3, V1', V2', V3 ').
15. The method of claims 13 to 14, wherein the method further comprises: -receiving a Vehicle Input Signal (VIS), wherein the Vehicle Input Signal (VIS) is related to at least a vehicle state and a battery pack state; -determining a trigger command of the system based at least on the Vehicle Input Signal (VIS), and -Preferably, receiving or generating a start-up instruction, wherein the trigger command of the system is further based on the start-up instruction, optionally based on at least one of the following: -a pre-defined time period for which, -A predefined distance, and -Instructions from the user or driver.

Description

Electrochemical impedance spectroscopy systems and methods Technical Field The present application relates to an electrochemical impedance spectroscopy system. The electrochemical impedance spectroscopy system is configured to determine an electrochemical impedance of a vehicle battery. To this end, the system is equipped with a battery management system that controls an activation power module configured to activate a vehicle battery. The system may also be configured to generate a battery cell degradation output based at least on the determined impedance. A corresponding method is also provided. Background An electric vehicle has at least an electric motor and a vehicle battery. In operation, the electric motor is adapted to provide propulsion for the vehicle, for example, to drive a driveline coupled to wheels of the vehicle. The electric vehicle may be a pure electric vehicle, an electric-only vehicle, or an all-electric vehicle. Electric vehicles may also include hybrid electric vehicles that combine a conventional internal combustion engine system with an electric propulsion system. Different types of batteries are used to power the motor. Lithium ion batteries are the most commonly used technology in electric vehicles. However, other types of vehicle batteries are known. In any event, it is critical to operate the vehicle battery within predefined safety limits to ensure the safety of the user as well as the electric vehicle. In use, the vehicle battery may experience aging, wear, or degradation. The purpose of monitoring and controlling the (high voltage) vehicle battery in an electric vehicle throughout its life cycle is to maximize efficiency while extending its remaining useful life. State of health (SOH) of a vehicle battery refers to a measure of the current condition or performance of the vehicle battery as compared to its ideal or original state when new. SOH is typically expressed in terms of percentage, where 100% indicates that the vehicle battery is in a perfect condition and a lower percentage indicates aging, wear, or degradation. In fact, SOH helps to assess the remaining useful life of the vehicle battery and indicates when replacement or maintenance may be required. Improvements and optimization of energy management and extension of battery life are key topics for the automotive industry. Recent innovations in computing and electronics have led to significant advances in implementation of battery control. The use of novel artificial intelligence and other predictive models helps to improve the accuracy of battery state estimation. The remaining life of the battery is closely related to SOH. In addition, battery degradation may lead to dangerous events, with thermal runaway being the most well known. The state of safety (SOS) of a vehicle battery refers to an assessment of the battery's state of safety, ensuring that it operates without risk of such as fire, explosion, leakage or other dangerous conditions. SOS evaluates the ability of a vehicle battery to safely operate under normal and pressure conditions, including extreme temperatures, overcharging, physical damage, and other environmental factors. Therefore, monitoring SOS is also an important index to be considered in the technical field of electric automobiles. State of charge (SOC) may be defined as an indication of the current charge level of the vehicle battery, typically expressed in percent, showing how much energy is available. Existing algorithms have achieved significant results in estimating SOC, however, SOH requires more complex algorithms, while SOS remains challenging for calculation of electric vehicle batteries. In the known prior art, algorithms for SOH and SOS in battery management systems rely on measurement signals from the vehicle battery. In particular, known battery management systems utilize direct measurements (e.g., voltage, current, and temperature) to calculate these metrics. However, the accuracy of these calculations depends on the performance of the underlying algorithm. It is therefore desirable to provide a system and method for determining the electrochemical impedance of a vehicle battery that obviates the above-described drawbacks and provides an advantageous solution to the shortcomings of the prior art. Disclosure of Invention It is an object of the present invention to provide an electrochemical impedance spectroscopy system configured at least to determine the electrochemical impedance of a vehicle battery. For clarity and brevity, this electrochemical impedance spectrum will be referred to hereinafter collectively as the present system. The system includes a vehicle battery, a battery management system, or a BMS. A plurality of voltage sensors may further be provided, preferably as part of a battery management system. The system also includes an excitation power supply module and a current sensor. The vehicle battery is arranged within the motor vehicle (for driving a configured motor) to