Combination heatsink and battery heater for electronic devices
Some embodiments provide a novel method for harnessing the heat generated by one or more components (e.g., a set of IR LEDs) of an A/V recording and communication device in order to manage the temperature of one or more batteries of the A/V recording and communication device. Some aspects of the present embodiments raise the temperature of the battery in a cold weather without requiring any additional electrical power (e.g., without consuming any additional power for heating up the battery). In one aspect of the present embodiments, a thermally conductive sheet is coupled to a printed circuit board to which one or more IR LEDs are coupled. The thermally conductive sheet transfers the waste heat generated by the IR LEDs of the A/V recording and communication device to a rechargeable battery of the device.
1. An audio/video (A/V) recording and communication device, comprising:
a camera;
a printed circuit board (PCB);
one or more infrared (IR) illuminators coupled to a first surface of the PCB and configured to illuminate a field of view of the camera with IR light;
a thermally conductive sheet having a first portion coupled to a second surface of the PCB and a second portion extending from the PCB; and
a rechargeable battery thermally coupled to the one or more IR illuminators through the thermally conductive sheet such that heat dissipation of the one or more IR illuminators warms the rechargeable battery.
2. The device of claim 1 , further comprising a heatsink coupled to the second surface of the PCB, wherein the thermally conductive sheet is sandwiched between the PCB and the heatsink.
3. The device of claim 1 , wherein the thermally conductive sheet is thermally coupled to the rechargeable battery by proximity through convection through air.
4. The device of claim 1 , wherein the thermally conductive sheet comprises copper.
5. The device of claim 1 , wherein the one or more IR illuminators comprises at least one IR light-emitting diode (LED).
6. The device of claim 1 , wherein the rechargeable battery comprises a lithium-ion battery.
7. The device of claim 1 , further comprising a processor, wherein the processor is configured to monitor a temperature of the rechargeable battery and to control an amount of electrical power delivered to the one or more illuminators.
8. The device of claim 1 , further comprising a resistive battery heater contacting the rechargeable battery.
9. The device of claim 8 , wherein the resistive battery heater is located on a side of the rechargeable battery opposite the thermally conductive sheet.
10. The device of claim 2 , wherein a surface area of the second portion of the thermally conductive sheet is at least as large as a surface area of the heatsink.
11. The device of claim 1 , wherein the PCB has a metal core.
12. The device of claim 1 , wherein the thermally conductive sheet is thermally coupled to the rechargeable battery by direct contact.
13. The device of claim 1 , wherein the thermally conductive sheet comprises a copper alloy.
14. The device of claim 1 , further comprising a processor, wherein the processor is configured to monitor a temperature of the rechargeable battery and to control a time duration of electrical power delivered to the one or more IR illuminators.
15. The device of claim 1 , wherein a temperature of the rechargeable battery is raised from a first temperature, below or equal to a threshold temperature, to a second temperature above the threshold temperature.
16. The device of claim 1 , wherein the second portion of the thermally conductive sheet is thermally coupled to the rechargeable battery.
17. The device of claim 16 , wherein the second portion of the thermally conductive sheet is thermally coupled to the rechargeable battery by direct contact.
18. The device of claim 8 , wherein the resistive battery heater and the thermally conductive sheet both provide heat to the rechargeable battery.
19. The device of claim 1 , wherein the rechargeable battery comprises a thermistor to determine a temperature of the rechargeable battery.
20. The device of claim 1 , wherein the rechargeable battery comprises a fuel gauge to determine a temperature of the rechargeable battery.
21. The device of claim 1 , further comprising a processor, wherein the processor is configured to:
receive a signal indicative of a temperature of the rechargeable battery;
determine that the temperature of the rechargeable battery is below a threshold temperature even when the heat dissipation of the one or more IR illuminators warms the rechargeable battery; and
increase an amount of electrical power provided to the one or more illuminators so that more heat dissipates from the one or more IR illuminators to the rechargeable battery.
22. The device of claim 1 , wherein electrical power is provided to the one or more illuminators by an alternating current (AC) power supply.