Battery state-of-health determination upon charging using state-of-health classifier
OwnerTina Shoa Hassani Lashidaniinventor
Life of this patent
Estimating the term…
Abstract
A rechargeable battery is charged and, at the same time, steps are taken to assess its state of health (SoH). The SoH is first broadly classified, which is only a coarse estimate. Next, the state of charge (SoC) is estimated, and then the SoC is repeatedly measured and predicted during charging until its value converges to a reliable value. The SoH is a state in the Kalman filter used for determining the SoC, and the SoH is also refined through the filter process. The SoH is reported when or after the SoC has converged, and is reported before charging is completed.
Claims20
A method of determining state of health (SoH) of a battery comprising the steps of:
- classifying the battery into one of multiple SoH classifications;
- estimating an initial value of a state of charge (SoC) of the battery;
- starting to charge the battery;
- repeatedly measuring a voltage across terminals of the battery as the battery is charged;
- repeatedly predicting values of the voltage across the terminals using an extended Kalman filter, wherein the SoH is a state of the extended Kalman filter;
- repeatedly comparing the predicted values with the measured voltages;
- determining that a difference between the predicted values and the measured voltages is below a threshold;
- obtaining a value of the SoH from the extended Kalman filter.
A battery charger for determining state of health (SoH) of a battery comprising:
- a battery interface that connects to the battery;
- a user interface;
- a processor connected to the battery interface and the user interface;
- a computer readable memory storing computer readable instructions, which, when executed by the processor, cause the battery charger to:
- classify the battery into one of multiple SoH classifications;
- estimate an initial value of a state of charge (SoC) of the battery;
- start to charge the battery;
- repeatedly measure a voltage across terminals of the battery as the battery is charged;
- repeatedly predict values of the voltage across the terminals using an extended Kalman filter, wherein the SoH is a state of the extended Kalman filter;
- repeatedly compare the predicted values with the measured voltages;
- determine that a difference between the predicted values and the measured voltages is below a threshold;
- obtain a value of the SoH from the extended Kalman filter;
- and
- output the calculated value of the SoH on the user interface.
Dependencies are inferred from the claim text.