Google filed a patent for a battery pack with embedded heaters to increase life of the batteries in the pack

Cold temperatures have negative effects on battery packs. For example, lithium ion battery packs generally lose substantial discharge capacity at sub-freezing temperatures and are even susceptible to irreversible damage if charged in sub-freezing temperatures.

The patented heater system includes a heating element interweaved between the battery cells of the battery pack and a heating controller electrically coupled to the heating element to drive current through the heating element and provide heat to the battery cells of the battery pack. The weaving of the heating element between the battery cells provides fixed mechanical support to the heating element.

The patented battery pack is ideal for unmanned air vehicles (UAVs) that fly at very high altitudes (e.g., 65,000 ft.).

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