Analysis of the reasons and solutions for the swelling of polymer lithium batteries
Analysis of the reasons and solutions for the swelling of polymer lithium batteries
Tags: battery swelling reasons, battery swelling, polymer lithium batteries swelling, LiMnO2 battery, ultra thin battery,lipo battery, swelling analysis and solutions,LP503562, lithium polymer battery,Lipo battery with a genuine 2-pin JST-PH connector
Aluminum-plastic film soft pack batteries mainly refer to lithium manganese soft pack batteries （LiMnO2 battery ultra thin battery）and lithium polymer batteries ( Lipo battery ). They have many obvious advantages such as: high energy density, high safety, miniaturization, ultra-thin, light weight, and easy customization. However, the disadvantage is also obvious, and it is easy to swell.
Let's take the lithium polymer battery / Lipo battery as an example to analyze the reasons and solutions for the expansion of the aluminum-plastic film soft-pack battery:
1. The polymer lithium battery is swelling and may not be broken. This kind of battery have a normal expansion rate. When the cell is charged, lithium ions are released from the positive electrode and embedded in the negative electrode, causing the gap between the negative electrode layers to increase, and expansion occurs. Generally speaking, the thicker the cell, the greater the expansion; the expansion rate 0%-3 before 300 cycles is normal.
2. Expansion caused by defect process control.
A. Sealing defect: During the sealing process in the production, air moisture enters the interior of the cell, causing the electrolyte to decompose and generate gas.
B. The water content of the battery exceeds the standard: in the process, once the water content exceeds the standard, the electrolyte will fail to produce gas.
C. Corrosion: The polymer soft-packed lithium battery core corrodes, the aluminum layer is consumed by the reaction, loses the barrier effect on water, and flatulence occurs.
3. Surface damage: Damaged by external force, puncturing causes moisture to enter the inside of the cell. The aluminum material is easy to be damaged, and it will be deformed with a slight knock. The larger the battery core and the larger the air pocket, the easier it is to be damaged.
4. Short circuit: The contact between the positive and negative electrodes leads to a short circuit, and the polymer lithium battery is inflated or even smoked.
5. Internal short circuit: Shrinkage, curling, breakage, burr piercing the separator, etc. of the polymer lithium battery separator will cause internal circuit breakage, resulting in bulging.
6. Overcharge and overdischarge: The polymer soft pack battery is overcharged or overdischarged, and the protective plate is abnormal, the battery cell will be seriously inflated.
Polymer lithium battery swelling solution:
The manufacturer must strictly control the water content, the turnover process , the baking time and temperature during the production process. During the packaging process, special blister trays should be used to separate the packaging to protect it, and collision and extrusion are strictly prohibited during transportation.
The user must stop using the lithium polymer battery pack after finding it abnormal swelling. The abnormal swelling polymer lithium battery pack is already a precursor to a big problem, and it is not recommended to use it again. Continued use may result in unimaginable consequences such as short circuit, heat generation, smoking, burning, etc. Lithium batteries have strict requirements on chargers. They cannot be sloppy charging if they can be connected to the power supply at will. You must use a special charger for lithium batteries. If the charger used does not meet the requirements, the polymer lithium battery will be bulged. , in severe cases, safety accidents and even explosions are possible.
See our LP503562 3.7V 1200mAh lithium polymer battery / Lipo battery with a genuine 2-pin JST-PH connector as shown and include the PCM, it also includes Protection Circuitry Board to ensure that it will not over-discharged/charged and are protected from short-circuits but you should still take care when using them.
Features:
3.7V nominal voltage
100mm JST terminated lead
Come 30% pre-charged for longer life storage
4.2V charging cut-off and 2.4V emergency discharge cut-off
Short circuit protection
Lithium-ion polymer (also known as 'lipo battery' or 'li-poly battery') batteries are thin, light, and powerful. The output ranges from 4.2V when completely charged to 3.7V. This battery has a capacity of 1200mAh for a total of about 4.5 Wh. If you need a larger battery, we also have a 2500mAh+ model
Choices for other Lithium Battery:
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Rechargeable solution | Primary solution | Primary solution | Primary solution | Rechargeable solution | |||||
