1.Compression
The low-temperature and low-pressure gaseous refrigerant flows out of the evaporator and is sucked in by the compressor. The compressor does work on this part of the gas (consuming electrical energy) and compresses it violently. When the refrigerant turns into high-temperature and high-pressure superheated vapor, the temperature of the vapor is much higher than the ambient temperature, creating conditions for heat release to the outside.
2. Condensation
The high-temperature and high-pressure refrigerant vapor enters the condenser (usually a finned tube heat exchanger composed of copper tubes and aluminum fins). The fan forces the ambient air to blow over the condenser fins. Subsequently, the refrigerant vapor releases heat to the flowing air in the condenser. Due to cooling, it gradually condenses from a gaseous state into a medium-temperature and high-pressure liquid. At this point, the heat is transferred from the refrigeration system to the outdoor environment.
3. Expansion
The medium-temperature and high-pressure liquid refrigerant flows through a narrow channel through the throttling device, which serves to throttle and reduce pressure, similar to blocking the opening of a water pipe with a finger. When the pressure of the refrigerant drops suddenly, the temperature also drops sharply, turning into a low-temperature and low-pressure gas-liquid two-phase mixture (mist).
4. Evaporation
The low-temperature and low-pressure gas-liquid mixture enters the evaporator, and another fan circulates the air inside the box through the cold evaporator fins. The refrigerant liquid absorbs the heat of the air flowing through the fins in the evaporator, rapidly evaporates and vaporizes, and reverts to a low-temperature and low-pressure gas. Due to the absorption of heat, the temperature of the air flowing through the evaporator drops significantly, thereby achieving the cooling of the test chamber.
Subsequently, this low-temperature and low-pressure gas is drawn into the compressor again, initiating the next cycle. In this way, the cycle repeats itself without end. The refrigeration system continuously "moves" the heat inside the box to the outside and dissipates the heat into the atmosphere through the fan.
1. Lithium-ion batteries: High and low temperature tests run through all R&D stages of lithium-ion batteries, from materials, cells to modules.
2. Material level: Evaluate the basic physical and chemical properties of basic materials such as positive and negative electrode materials, electrolytes, and separators at different temperatures. For instance, testing the lithium plating risk of anode materials at low temperatures, or examining the thermal shrinkage rate (MSDS) of separators at high temperatures.
3. Cell level: Simulate the cold winter in the frigid zone (such as -40℃ to -20℃), test the low-temperature start-up, discharge capacity and rate performance of the battery, and provide data support for improving low-temperature performance. Cyclic charge and discharge tests are conducted at high temperatures (such as 45℃ and 60℃) to accelerate aging and predict the long-term service life and capacity retention rate of the battery.
4. Fuel cells: Proton exchange membrane fuel cells (PEMFC) have extremely strict requirements for the management of water and heat. Cold start capability is a key technical bottleneck for the commercialization of fuel cells. The test chamber simulates an environment below freezing point (such as -30℃) to test whether the system can be successfully started after freezing and to study the mechanical damage of ice crystals to the catalytic layer and proton exchange membrane.
5. Photovoltaic materials: Solar panels need to serve outdoors for more than 25 years, enduring the harsh tests of day and night as well as the four seasons. By simulating the temperature difference between day and night (such as 200 cycles from -40℃ to 85℃), the thermal fatigue of the interconnect solder tape of the battery cells, the aging and yellowing of the encapsulation materials (EVA/POE), and the bonding reliability between different laminated materials can be tested to prevent delamination and failure.
Modern high and low temperature test chambers are no longer simple temperature change chambers, but intelligent testing platforms integrating multiple functions. The advanced test chamber is equipped with observation Windows and test holes, allowing researchers to monitor the samples in real time during temperature changes.
Get A Quote
IPv6 network supported