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Li-ion Power Battery Crush Test – Part 2

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  2.1 Test preparation Cylindrical and square batteries are commonly used as power cell. The research object of this paper is a square cell, which is mainly composed of nickel cobalt manganese positive electrode and graphite negative electrode chemical material system. Single battery size: X Y Z=W x L x H=27 mm x 148 mm x 94 mm, rated voltage: 3.7 V, rated capacity: 37 Ah.  The single battery is arranged in the module in the form of superposition along the width direction (X direction) of the single battery. In this paper, the definition of module crush direction is consistent with that of monomer, and the battery monomer and module are shown in Figure 3. The displacement, load, voltage, temperature data and video data of the crush process were collected by extruding the cell and module with the indenter, and the test results were analyzed.   2.2 Results of cell crush test   Carry out the XYZ crush working condition test on the electric core in these three directions...

Li-ion Power Battery Crush Test – Part 1

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  Guided and supported by policies, electric vehicles have entered a period of rapid development. The government and major engine manufacturers have formulated corresponding development plans for electric vehicles. In the future, electric vehicles will gradually replace traditional fuel vehicles.  However, after a series of reported electric vehicle collisions, fires and even explosions occurred again, making people focus on the safety of electric vehicles. The electric vehicle mainly uses the power battery as the power source, which leads to a series of problems such as power battery pack, high and low voltage wire harness and load end protection. However, due to the characteristics of integrated high voltage and high electric energy, the layout of power battery pack on the vehicle and collision protection need to be focused.   The existing laws and regulations put forward corresponding detection standards for the mechanical abuse of battery packs. However, under real ro...

What is Environmental Safety Test of Lithium-ion Battery ?

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  Lithium ion battery, as well as the overall sample consisting of non user replaceable battery/lithium ion battery and its electronic products. For non user replaceable batteries, they should be installed in electronic products as a whole sample for standard lithium ion battery environmental safety test;  For non user replaceable lithium-ion batteries, they can be placed in electronic products as a whole sample, or they can be taken out separately for standard environmental safety test of lithium-ion batteries. It is recommended that they be preferred as a whole sample for testing. As air leakage, smoke, fire and even explosion may occur during the test, necessary protective measures must be taken, such as placing the sample in a ventilation device with explosion-proof function.   1.Low Air Pressure Test purpose: The low pressure test is used to simulate the impact of low pressure conditions on the safety of lithium ion batteries during air transportation. After the test...

Low Pressure Environment and Thermal Runaway

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  While lithium battery brings convenience to people’s life, its safety is also concerned by everyone. The violent combustion of electrolyte will penetrate the metal plate, and the explosion limit of pyrolysis gas is higher than that of hydrocarbons.  The thermal runaway reaction of lithium battery is easy to cause dangerous events, and its high temperature characteristic is an important and basic parameter of fire hazard. Therefore, it is necessary to explore the impact of low-voltage environment on the thermal runaway release temperature of lithium batteries to reduce the risk of their use.   1. Overview of lithium battery Thermal Runaway The thermal runaway process of lithium battery includes two forms: primary explosion and combustion explosion. In the primary explosion stage, the internal temperature of the lithium battery will increase. If the pressure increases, the pressure relief port of the lithium battery will be opened and smoke will be continuously released....

About Battery Internal Short Circuit Test

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  The power lithium-ion battery has the advantages of high energy density, long service life, high rated voltage, high power bearing capacity and low self discharge efficiency, and has become the ideal power battery for hybrid electric vehicles and pure electric vehicles. However, the safety problem of lithium-ion battery has become the main factor preventing it from being widely used in the power field.   With the increase of the number of electric vehicles, their safety problems are increasingly prominent, and the safety problems of electric vehicles mainly come from their power system – lithium ion batteries. The safety problem of lithium-ion battery is mainly caused by fire and explosion caused by thermal runaway, and one of the reasons for thermal runaway is short circuit inside the battery.   At present, the research on thermal runaway of lithium-ion battery mainly focuses on the modeling analysis and experimental analysis of one type of battery. This paper adopts d...