Lithium particle batteries have become one of the primary power hotspots for convenient electronic items, for example, portable interchanges and workstations because of their high unambiguous energy and high voltage. Be that as it may, under harmful circumstances like warming, cheating, over release hamper, pressure, and so on, lithium-particle batteries might encounter episodes like fire, blast, and, surprisingly, individual injury, bringing about countless lithium-particle batteries being reviewed.
Consequently, how to further develop the security execution of lithium-particle batteries has turned into a central point of contention in their turn of events. Right now, numerous nations or testing foundations have created pertinent security testing techniques for lithium-particle batteries. Lithium particle batteries should breeze through wellbeing assessments to decrease their use gambles. The global guidelines connected with the wellbeing of lithium-particle batteries essentially incorporate IEC 62133, IEC 62281, UL 1642, UL 2054, UN 38.3, and so on.
In the above norms, the weighty item influence test is an undertaking that mimics the inner short out of lithium-particle batteries. This article led weighty item influence tests on various models of lithium-particle batteries as indicated by the necessities of the norm. The experimental outcomes were looked at and examined by destroying the battery after the trial.
1 Test
1.1 Test gear and climate
The testing instrument is the DGBELL blast resistant effect test chamber. The surrounding temperature during the examination was constantly kept up with at (20 ± 5) ℃.
1.2 Test tests
The lithium-particle battery tests utilized in this trial are as per the following: 18650 round and hollow lithium-particle battery; Square aluminum shell battery; Square lithium-particle polymer battery
1.3 Test strategies
Place lithium-particle batteries of various shapes on a level surface, place a 15.8 mm width iron pole evenly at the focal point of the battery, and let a 9.1 kg hammer tumble from a level of (610 ± 15) m onto the battery. For square batteries, they ought to likewise be pivoted 90 ° along the long hub to endure weighty effects on both the wide and tight surfaces. The temperature on the outer layer of the battery during the trial is observed by a thermocouple joined to the outer layer of the battery.
2 Outcomes
2.1 18650 lithium-particle batteries
In the wake of being hit by a weighty item, a profound imprint is left on the outer layer of the battery, which is fundamentally brought about by the pressure of the iron bar put on the outer layer of the battery subsequent to being hit by a weighty mallet. Rust showed up on the outer layer of the positive post of the battery, essentially because of the launch of the inside pressure alleviation valve during the effect test, making some electrolyte stream out. The electrolyte delivered destructive substances after experiencing air, bringing about the erosion of the positive shaft cap.
Subsequent to dismantling the battery packaging, breaks showed up on the outer layer of the battery cells. This is for the most part credited to the expansion and misshapening of the anodes brought about by the iron pole crushing the battery. The battery cell was unfurled, and both the anode and the initial film broke where the iron bar was crushed. The positive and negative terminal covering materials have encountered separation.
2.2 Square battery
(1) Aluminum shell battery
For square lithium-particle batteries, there are by and large two bundling structures: aluminum shell and aluminum-plastic.
The battery additionally showed imprints because of the pressure of the iron pole and turned out to be extremely slender in the center. Subsequent to dismantling the aluminum shell, it tends to be seen that the interior battery cells have been partitioned into equal parts. By unfurling the battery cell, it tends to be seen that the covering of the battery material has stripped off, and the terminals are badly crumpled. This is because of the effect of the iron bar on the inside of the battery, which creates pressing power in the plane bearing. Also, the high hardness of the aluminum shell upsets the expansion of the battery cell in the level course, bringing about wrinkling of the cathodes.
After the thin surface trial of the square battery, the restricted surface course of the battery has been totally crushed and twisted. In the wake of dismantling the battery packaging, it was found that the inside battery cells had serious breaks. After unfurling the terminal, it was found that the dynamic material had tumbled off and the stomach had burst.
(2) Lithium particle polymer batteries
For lithium-particle polymer batteries bundled in aluminum-plastic. The consequences of the battery test are like those of aluminum shell bundled batteries. Nonetheless, because of the warm fixing of the aluminum-plastic shell, the inner battery cells are presented to outside powers after the battery test. Besides, because of the dainty thickness of the aluminum-plastic bundling battery, it was separated into two sections under outside influence.
2.3 Conversation of Experimental outcomes
From the above test results, it very well may be seen that the weighty article influence test can recreate the inside short out of lithium-particle batteries. In the weighty article influence test, the battery was exposed to outside powers, causing deformity of the battery packaging. Also, it caused distortion of the battery cell, causing strain on the anodes and separator. Under the activity of this pressure, the anode material will encounter separation, and the stomach will crack because of its slenderness, bringing about direct electronic conduction between the positive and negative terminal materials, or contact between the copper (aluminum) authority and the positive (negative) cathode material (for example inside impede), in locally enormous release current and Ohmic intensity.
Because of inside shortcircuits happening in numerous areas, the intensity produced causes opposite side responses, like cathode decay and electrolyte disintegration. During the trial, there was a huge expansion in battery temperature. For the 18650 lithium-particle battery model, an inward short out produced a lot of gas, causing an expansion in interior strain. In the wake of arriving at a specific worth, the battery pressure help valve opened to deliver acidic gas, at last staying away from the event of wellbeing mishaps. For square lithium-particle batteries, their thickness is generally little. In case of outside influence, the battery might burst or part fifty. At the point when an inside cut off, the inward parts of the battery are straightforwardly presented to the air and respond.
3 End
Through weighty article influence tests on various sorts of lithium-particle individual batteries, it very well may be seen that this test technique can successfully recreate what is happening of inward shortcircuits in batteries. The dismantling examination of various sorts of batteries observed that there were cathode breakage and stomach crack inside the batteries, bringing about inner shortcircuits inside the batteries. The investigation and comprehension of this exploratory peculiarity will be more useful for battery makers to figure out the testing principles of batteries, accordingly further developing the item nature of lithium-particle batteries and upgrading their security.
