The present invention relates to a method for determining a state of charge of a battery, including: (a) acquiring a state of charge of the battery at a current sampling time point tn; (b) acquiring a voltage Vn, a temperature Tn, and a charging rate Cn of the battery at the current sampling time point tn, and a voltage Vi of the battery at a sampling time point ti, and calculating a voltage difference Vn−Vi between the voltage Vn and the voltage Vi; (c) when the voltage difference Vn−Vi is greater than or equal to a preset voltage threshold, calculating a voltage change rate; and (d) when the voltage change rate is greater than or equal to a preset voltage change rate threshold for the first time, acquiring a corrected state of charge of the battery as an actual state of charge of the battery.

The present invention relates to a method for determining a state of charge of a battery, including: (a) acquiring a state of charge of the battery at a current sampling time point tn; (b) acquiring a voltage Vn, a temperature Tn, and a charging rate Cn of the battery at the current sampling time point tn, and a voltage Vi of the battery at a sampling time point ti, and calculating a voltage difference Vn−Vi between the voltage Vn and the voltage Vi; (c) when the voltage difference Vn−Vi is greater than or equal to a preset voltage threshold, calculating a voltage change rate; and (d) when the voltage change rate is greater than or equal to a preset voltage change rate threshold for the first time, acquiring a corrected state of charge of the battery as an actual state of charge of the battery.

A controller generates a first command for battery array sensors to sense voltages of battery cell arrays of a traction battery, and generates a second command to sample a value of current through the traction battery at a time following the first command that is defined by durations of analog to digital conversion operations of some of the battery array sensors and an analog to digital conversion operation associated with sampling the value.

A controller generates a first command for battery array sensors to sense voltages of battery cell arrays of a traction battery, and generates a second command to sample a value of current through the traction battery at a time following the first command that is defined by durations of analog to digital conversion operations of some of the battery array sensors and an analog to digital conversion operation associated with sampling the value.

A method and a system for detecting vehicle battery cell imbalance are provided. The method includes: acquiring a plurality of raw vehicle data of a target vehicle type in a preset time period; grouping the plurality of raw vehicle data into a predefined number of bins based on the data type and the value range of raw vehicle data; determining an observed bin-level cell voltage imbalance of the bin based on the raw vehicle data in each bin; building machine learning model to predict bin-level cell voltage imbalance of each bin, based on bin parameters defined; determining a difference between observed bin-level cell voltage imbalance and predicted bin-level cell voltage imbalance of each bin, to obtain an unaccounted bin-level cell voltage imbalance; and determining whether there is a high risk of cell imbalance in a target vehicle based on a weighted average of unaccounted bin-level cell voltage imbalances.

A method and a system for detecting vehicle battery cell imbalance are provided. The method includes: acquiring a plurality of raw vehicle data of a target vehicle type in a preset time period; grouping the plurality of raw vehicle data into a predefined number of bins based on the data type and the value range of raw vehicle data; determining an observed bin-level cell voltage imbalance of the bin based on the raw vehicle data in each bin; building machine learning model to predict bin-level cell voltage imbalance of each bin, based on bin parameters defined; determining a difference between observed bin-level cell voltage imbalance and predicted bin-level cell voltage imbalance of each bin, to obtain an unaccounted bin-level cell voltage imbalance; and determining whether there is a high risk of cell imbalance in a target vehicle based on a weighted average of unaccounted bin-level cell voltage imbalances.

The present disclosure provides methods for determining impedance of an electrochemical device by electrically connecting a variable impedance in parallel with the electrochemical device; electrically connecting a power supply to the electrochemical device, the power supply generating a power supply current; modulating a current through the variable impedance; measuring a stack current flowing through the electrochemical device; measuring, at the electrochemical device, a voltage across at least a portion of the electrochemical device; and calculating, based on the measured stack current and the measured voltage, the impedance of the electrochemical device. Systems for performing such methods are also provided.

The present disclosure provides methods for determining impedance of an electrochemical device by electrically connecting a variable impedance in parallel with the electrochemical device; electrically connecting a power supply to the electrochemical device, the power supply generating a power supply current; modulating a current through the variable impedance; measuring a stack current flowing through the electrochemical device; measuring, at the electrochemical device, a voltage across at least a portion of the electrochemical device; and calculating, based on the measured stack current and the measured voltage, the impedance of the electrochemical device. Systems for performing such methods are also provided.

A voltage detection circuit is provided for measuring each cell voltage of an assembled battery configured by connecting a plurality of cells in series. The voltage detection circuit is defined as a first voltage detection circuit. The voltage detection circuit includes a downstream communication circuit that communicates with a host apparatus to communicate with a plurality of voltage detection circuits connected in series with each other; a reply signal generation circuit that generates a reply signal containing data detected by the first voltage detection circuit; an upstream transfer circuit that transfers a signal received by the upstream communication circuit to downstream; a dummy current consumption circuit that consumes a predetermined dummy current; and a control circuit that controls the reply signal generation circuit, the upstream transfer circuit, and the dummy current consumption circuit to selectively operate any one of them.

A voltage detection circuit is provided for measuring each cell voltage of an assembled battery configured by connecting a plurality of cells in series. The voltage detection circuit is defined as a first voltage detection circuit. The voltage detection circuit includes a downstream communication circuit that communicates with a host apparatus to communicate with a plurality of voltage detection circuits connected in series with each other; a reply signal generation circuit that generates a reply signal containing data detected by the first voltage detection circuit; an upstream transfer circuit that transfers a signal received by the upstream communication circuit to downstream; a dummy current consumption circuit that consumes a predetermined dummy current; and a control circuit that controls the reply signal generation circuit, the upstream transfer circuit, and the dummy current consumption circuit to selectively operate any one of them.