Abstract: A method, an apparatus, and a system for determining a state of a battery are provided. The method includes acquiring battery information from a sensor associated with the battery. The battery information includes at least terminal voltage and a terminal current. The method further includes estimating degradation information based on a first principle degradation model and the battery information. The first principle degradation model is a three dimensional model that includes a plurality of layers having one or more attributes representative of physical parameters of the battery. The method further includes identifying a circuit model based on the degradation information and the battery information, determining the state of the battery using the identified circuit model, and implementing a control action or a notification based on the determined state of the battery.

Abstract: An automatic solar collector system useful for heating and storing a heating fluid such as, for example, water. The automatic solar collector system of this invention is characterized by its construction including a photo cell-actuated hydraulic cylinder whereby the collector panel may be positioned at an angle to focus the sun's rays onto the fluid conduit disposed within the collector panel. Overall operation of the automatic solar collector system of this invention is regulated by a clock timer, and the entire system is essentially self-contained so that it may easily be moved from one location to another, or put in parts to be attached to a home or a building with the tank and controls below the roof.