METHOD FOR CHARGING A BATTERY USING A THERMAL MODEL FOR AN ELECTRICAL DEVICE CONNECTED TO THE BATTERY

A method for charging a battery includes coupling an electrical device in a circuit between the battery and an electrical power source. The electrical device having on and off states that are mechanically different. The method includes charging the battery by setting the electrical device to the on state, measuring current flowing through contacts of the electrical device while in the on state, determining current as a function of time flowing through the contacts of the electrical device, using the current as a function of time as a variable in a thermal model based on heating of the contacts and cooling of the contacts, determining by the thermal model a predicted temperature of the contacts based on the current as a function of time and the heating and cooling of the contacts and controlling the on and off state of the electrical device based on the predicted temperature.