Abstract: System and methods for estimating a life of a battery pack are presented. In certain embodiments, a method for estimating a life of a battery pack may include generating cell-level test data that includes measured parameters a of battery cell included in the battery pack in response to a plurality of test conditions. One or more first thermal response parameters associated with the battery cells of the battery pack may be determined. A battery cell aging model may be generated based, at least in part, on the cell-level test data and the one or more first thermal response parameters. Second thermal response parameters associated with the battery pack may be determined, and an estimated life of the battery pack may be determined based, at least in part, on the battery cell aging model and the second thermal response parameters.

Abstract: Disclosed herein are various systems and methods for capturing and utilizing temperature information in a battery pack. An electrical measurement system may be configured to determine a subdivision electrical parameter associated with one or more subdivisions, and a thermal measurement system configured to determine and track a thermal parameter associated with one or more subdivisions. A battery model may utilize the thermal parameter and the electrical parameter to estimate a characteristic of one or more battery subdivisions. In some embodiments, the battery model may further estimate a second thermal parameter of a second subdivision based upon a location of the second subdivision within the battery pack and based on the estimated characteristic of a first subdivision. Some embodiments may further estimate a life assessment of one or more subdivisions based at least in part on the subdivision electrical parameter and the thermal parameter.

Abstract: System and methods for estimating a life of a battery pack are presented. In certain embodiments, a method for estimating a life of a battery pack may include generating cell-level test data that includes measured parameters a of battery cell included in the battery pack in response to a plurality of test conditions. One or more first thermal response parameters associated with the battery cells of the battery pack may be determined. A battery cell aging model may be generated based, at least in part, on the cell-level test data and the one or more first thermal response parameters. Second thermal response parameters associated with the battery pack may be determined, and an estimated life of the battery pack may be determined based, at least in part, on the battery cell aging model and the second thermal response parameters.

Abstract: A method for modeling changes in the state of charge vs. open circuit voltage (SOC-OCV) curve for a lithium-ion battery cell as it ages. During battery pack charging, voltage and current data are gathered for a battery cell. A set of state equations are used to determine the stoichiometry and state of charge of the cathode half-cell based on the charging current profile over time. The voltage and current data, along with the stoichiometry and state of charge of the cathode half-cell, are then used to estimate maximum and minimum solid concentration values at the anode, using an error function parameter regression/optimization. With stoichiometric conditions at both the cathode and anode calculated, the cell's capacity and a new SOC-OCV curve can be determined.

Abstract: Disclosed herein are various systems and methods for capturing and utilizing temperature information in a battery pack. An electrical measurement system may be configured to determine a subdivision electrical parameter associated with one or more subdivisions, and a thermal measurement system configured to determine and track a thermal parameter associated with one or more subdivisions. A battery model may utilize the thermal parameter and the electrical parameter to estimate a characteristic of one or more battery subdivisions. In some embodiments, the battery model may further estimate a second thermal parameter of a second subdivision based upon a location of the second subdivision within the battery pack and based on the estimated characteristic of a first subdivision. Some embodiments may further estimate a life assessment of one or more subdivisions based at least in part on the subdivision electrical parameter and the thermal parameter.

Abstract: A method for modeling changes in the state of charge vs. open circuit voltage (SOC-OCV) curve for a lithium-ion battery cell as it ages. During battery pack charging, voltage and current data are gathered for a battery cell. A set of state equations are used to determine the stoichiometry and state of charge of the cathode half-cell based on the charging current profile over time. The voltage and current data, along with the stoichiometry and state of charge of the cathode half-cell, are then used to estimate maximum and minimum solid concentration values at the anode, using an error function parameter regression/optimization. With stoichiometric conditions at both the cathode and anode calculated, the cell's capacity and a new SOC-OCV curve can be determined.