Testing Chambers Knowledge

 1. Overcharged Overcharging of 18650 lithium batteries is a common cause of explosions. Lithium batteries must operate within the specified voltage range, otherwise there may be a safety hazard of explosion and fire. For example, the conventional voltage for ternary lithium batteries is 2.5V~4.2V; The conventional range for lithium iron phosphate batteries is 2.0V~3.65V.   When charging an 18650 lithium battery, the lithium ions in the positive electrode move to the negative electrode and are embedded in the mesh structure of the negative electrode material. If the lithium ion battery is overcharged, it is easy to cause lithium deposition in the negative electrode, resulting in lithium crystallization and piercing the separator, which can cause a short circuit inside the battery cell and trigger an explosion.   That's why an overcharge protection circuit must be added to lithium-ion batteries during charging to provide overcharge protection. The lithium battery...

 1. Basic Introduction The research and application of power batteries for electric vehicles have gone through the development process from aluminum acid batteries, nickel hydrogen batteries to lithium batteries, and lithium batteries have also gone through the development process from metallic lithium to lithium compounds and now to lithium-ion batteries.   Lithium ion power batteries are mainly composed of battery cells, battery packs, or battery systems. Due to the activity of lithium ions on metal surfaces in lithium-ion batteries, there may be safety and stability issues in the development, use, and testing of lithium-ion batteries, which need to be prevented and eliminated.   2 Dangerous reasons The battery cells of lithium-ion batteries are the main components that cause fires and explosions during use and testing. The reasons for their hazards can be summarized as follows:   2.1 Short circuit (1) External short circuit The short circuit be...

The safety issue of power batteries can be summarized as "thermal runaway", which means that after reaching a certain temperature, it becomes uncontrollable, the temperature rises sharply, and then it will burn and explode. Overheating, overcharging, internal short circuits, collisions, etc. are several key factors that can cause thermal runaway of power batteries. (1) Overheating leads to overheating and loss of control The reasons for overheating of power batteries come from unreasonable battery selection and thermal design, or from external short circuits causing the temperature of the battery to rise, loose cable joints, etc. It should be solved from two aspects: battery design and battery management. From the perspective of battery material design, materials can be developed to prevent thermal runaway and block the reaction of thermal runaway; From the perspective of battery management, different temperature ranges can be predicted to define different safety levels for g...

The temperature and humidity environmenttest chamber , also known as the high and low temperature humid heat test chamber, temperature and humidity cycle test chamber, etc., is a commonly used environmental simulation system and equipment in laboratories and factories.   The temperature and humidity environment test chamber is used to simulate natural environments such as high temperature, low temperature, humidity, and dryness to test the performance stability of materials or products in various environments. So how to choose a suitable temperature and humidity environment test chamber? Here, I will specifically explain how to choose a temperature and humidity environment test chamber from several aspects such as volume, temperature, humidity, and control methods.   1. Capacity selection Place the tested product (component, assembly, part or whole machine) in a climate environment test chamber for testing to ensure that the surrounding environment of the tested prod...