Battery is the main power source of the product, it can drive the operation of the equipment, the use of test tools for detailed testing of the battery, can ensure the safety of the battery, to prevent the battery because of the high temperature produces spontaneous combustion and explosion and other situations, and the car is the main means of transportation, the frequency of use is very high, so in order to ensure that the driver's safety of the battery is imperative, the test method is to simulate a variety of Accident situation, to determine whether the quality of the battery is qualified, to observe whether the battery explosion phenomenon, the use of these tests can effectively avoid the risk of maintaining stability.
1, cycle life
Lithium battery cycle number of times, the reaction is the battery can be repeatedly charged and discharged with how many times. According to the different environments where lithium batteries are used, the cycle life can test the battery in low temperature, room temperature and high temperature cycle life can reach how much. Usually according to the use of the battery to choose the battery waste standards, if the battery is used for power batteries (electric vehicles, electric forklifts), etc., generally choose the discharge capacity maintenance rate of 80% as the standard parameter for disposal, while the battery can be used for energy storage, power storage, etc. can be relaxed to 60%. We often contact the battery, if the discharge capacity/initial discharge capacity is less than 60% there is no need to use, can not last half a day.
Nowadays, lithium batteries are not only used for 3C, but also more and more in the application of power batteries, electric vehicles traveling under different working conditions, the need to change the current. In the fast pace of life at the moment, the shortage of electric vehicle charging piles on the lithium battery fast charging requirements are also getting higher and higher. Therefore, the multiplier performance of lithium batteries needs to be tested. It can be tested according to the national standard of power battery. Now domestic and foreign battery factories are producing special high-multiplier batteries to meet market needs, the design of high-multiplier batteries can start from the type of living matter, pole surface density, compaction density, pole lugs selection, welding process, and the assembly process, interested friends can understand for themselves.
3、Quality and safety test
Q safety can be said to be a battery users are very concerned about the issue, whether it is the explosion of cell phone batteries, or electric cars on fire, etc. are enough to make people scared. The safety of lithium batteries must be inspected by the project, the safety test includes overcharge, overdischarge, short circuit, drop, heating, vibration, extrusion, pinprick, etc., but according to lithium pie, these safety tests are passive safety tests, meaning that the battery is put in a block of take to allow foreign objects to actively destroy the battery to test the battery enough safety. When sent for inspection, the need for the battery, the module is designed accordingly to do the safety test, but in the actual use of the process, such as an electric car out of control hit another car or object, is an irregular collision, may face more complex situations, but so that the cost of testing is higher, can only choose relatively reliable test content.
4, low temperature discharge, high temperature discharge
The effect of temperature on the discharge performance of the battery directly reacts to the discharge capacity and discharge voltage. Temperature decreases, the battery internal resistance increases, the electrochemical reaction slows down, the polarization internal resistance increases rapidly, the battery discharge capacity and discharge platform decreases, affecting the battery power and energy output.
For lithium-ion batteries, low-temperature conditions, the discharge capacity drops sharply, but in the case of high-temperature discharge capacity is not lower than room temperature, and sometimes slightly higher than the capacity at room temperature, mainly because of the accelerated migration of lithium ions at high temperatures, lithium electrodes are not like nickel electrodes and hydrogen storage electrodes at high temperatures to produce a decomposition or the formation of hydrogen to make the capacity drop. Battery module low-temperature discharge, as the discharge proceeds, due to resistance and other reasons to generate heat, so that the battery temperature rises, manifested in the phenomenon of voltage has risen, as the discharge proceeds, the voltage and then gradually decline.
Currently on the market to ternary batteries, lithium iron phosphate batteries, ternary batteries due to the collapse of the structure of the material at high temperatures will be unstable, than the lithium iron phosphate batteries, the security of the Q is much worse, but its energy density is higher than that of lithium iron phosphate, so the development of the two systems in the coexistence of the two.