Battery heating methods and systems

Abstract

This patent provides a battery heating technique that preheats the battery from extreme cold condition (e.g., −30° C.) to an appropriate operating temperature. This technique belongs to the battery energy storage and application field. The battery heating system includes a simple external control circuit and a battery (or battery pack) for heating. During the heating stage, the external control circuit and battery (or battery pack) forms a close loop. A continuous and pulse current will flow through the battery and generate joule heat on the battery internal resistance to preheat the battery (or battery pack). The heating technique can be used on any types of batteries without changing their internal and external structures, and this technique is low cost and can preheats the battery (or battery pack) from −30° C. to 0° C. in one minute. By using the internal resistance as the heat source, the heating technique can heat the battery (or battery pack) uniformly and is of high efficiency.