Many modern devices make use of lithium-ion batteries in a pretty robust manner, such as electric cars and smartphones. However, the problem with the batteries’ use is once they are used in extreme heat or cold, one will find them to be highly susceptible to malfunctions and low performance because of the temperature.
The problem might have been finally solved by a ‘Thermal Switch.’ The device works by opening itself at a high temperature and re-closes when the temperature turns cold. A thermal switch might be a bimetallic strip that usually comes encased within a tubular glass bulb so that it has protection from dust as well as a short circuit.
The engineers demonstrated a “thermal switch” comprising compressible graphene foam. The novel switch has the capability of dynamically adjusting temperatures both within the device and outside of it, thus maintaining consistent thermal management. The development is a huge contribution towards Thermal Switches Market as it has the potential to enhanced the lithium-ion batteries and subsequently the wide devices that makes use of it.
The newly developed graphene foam compresses physically from 1.2 mm to 0.2 mm. The team stated that its thermal conductance increases by a total factor of 8. The consequence of it is that the amount of heat conducted out is also completely adjustable. This is done in accordance with temperature conditions present inside and outside of the device resulting in better performance and energy efficiency.
The researchers evaluated the thermal conductance of the foam. They did so by sandwiching a 1.2 millimeter-thick sample made up of graphene foam in between a heat sink and a heater. Thereafter, they placed the system under an infrared microscope in order to measure the temperature along with the heat flow.
Meanwhile, fully compressing the foam to a 0.2-millimeter thickness, they saw an increase of thermal conductance by a factor of 8. After this, the researchers tested their experiment in a chamber that had the capability of creating specific environmental conditions. They also saw similar results with ambient temperatures from 0° C to 30°C, i.e., 32° F to 86° F.
The accomplishment achieved by the researchers would go a long way in developing lithium-ion batteries and might even help to bring much better devices that would overcome the present problems faced with the batteries.