The comprehensive performance of lithium battery, such as specific capacity, no memory effect, long life and environmental protection, far exceeds that of other secondary batteries. Lithium battery is called the ultimate battery, but why there is no lithium battery in the field of large-capacity battery? The key issue is the safety of lithium batteries. The biggest safety hidden danger of lithium ion battery explosion, leakage etc.
Cause:
1. Internal short circuit: It is the biggest hidden trouble cause of lithium ion battery, because in the production process of lithium ion battery, there are many reasons such as burrs, breakage, powders and bubbles in the positive and negative electrodes. During use, under overcharge (or even normal charge-discharge), lithium ions accumulate at the negative pole to form dendrites, piercing the diaphragm and forming an internal short circuit.
2. High current generation: external short circuit, internal short circuit will produce hundreds of amperes or more of excessive current.
A. When the external short circuit is short, due to the low external load, the battery will immediately discharge with A large current. A great deal of energy is expended in internal resistance, producing a great deal of heat.
B. Internal short circuit, the main reason is that the diaphragm is penetrated and large current is formed inside. The rising temperature causes the diaphragm to melt and the short circuit area to expand.
3. High current generation: external short circuit, internal short circuit will produce hundreds of amperes or more of excessive current.
A. When the external short circuit is short, due to the low external load, the battery will immediately discharge with A large current. A great deal of energy is expended in internal resistance, producing a great deal of heat.
B. Internal short circuit, the main reason is that the diaphragm is penetrated and large current is formed inside. The rising temperature causes the diaphragm to melt and the short circuit area to expand.
4. Burning: heat from the high current, at the same time, under the condition of high voltage (more than 5 v), the positive lithium oxide can also occur oxidation reaction, precipitation, metallic lithium in gas lead to the rupture of shell case, direct contact with air, lead to combustion, ignition electrolyte at the same time, a strong fire, gas rapid expansion, an explosion.
5. External factors: such as acupuncture and impact temperature rise, rapid expansion of gas, explosion.
Because lithium batteries have some potential safety problems, it is particularly important to test the safety of batteries. TOB has been engaged in the battery industry for 16 years. Our battery safety tester can effectively eliminate various battery safety hazards for you and protect your production and life.
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