How to repair lithium battery swelling?

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How to repair lithium battery swelling?

How to repair lithium battery swelling? Jan. 04, 2024

How to repair lithium battery swelling?

How to repair lithium battery swelling?


What should we do if the lithium battery swell due to heat? How to fix it? Lithium-ion batteries often have swelling during the manufacturing and use process. When lithium batteries are charged, lithium ions are extracted from the positive electrode and inserted into the negative electrode, causing the gap between the negative electrode layers to increase and expansion. Generally speaking, the thicker the battery cell, the greater its expansion. The swollen battery is scrapped and cannot be repaired. It is recommended to hand over the battery to a recycling company for recycling.


What should we do if the lithium battery swell due to heat?

Lithium battery swelling, also known as bulging, is because the internal positive and negative chemical materials are short-circuited, super current, internal puncture short-circuit and other reasons, which cause rapid changes in internal chemical substances, and the internal gas is generated due to high temperature. , And the battery is a highly sealed product, this generated gas cannot be discharged, only the expansion of the shell deformation, has produced a larger space to store the gas. The bottom and sides of the battery are thicker than the front and back, and the area is smaller, so the drum is played on the front and back.


This kind of swollen lithium battery is basically unusable. The load capacity becomes worse, and it will be fully charged at once, but it will be out of power when you call, or the use time is very short, and the phenomenon of power off and on again .


There is electrolyte in the lithium battery. After multiple re-discharges, part of the electrolyte decomposes to produce gas, which causes the battery to expand. Do not use lithium batteries with severe swelling. The current commercial lithium batteries are basically all electrolytes configured with lithium hexafluorophosphate. When the temperature is high, they begin to decompose, chemically react with the solution, and release gases such as carbon dioxide. The development of lithium salts for new electrolytes cannot be overcome for the time being. Try not to use it for a long time at high temperatures.


What are the reasons for the swelling of lithium batteries?

1. Over-discharge and over-charge of lithium battery;


2. Micro short circuit, that is the diaphragm is damaged, which leads to partial contact between the positive and negative electrodes of the battery;


3. Continuous floating charge of lithium battery at high temperature causes side reactions in the electrolyte, and high-rate charge and discharge at high temperature. This problem will not occur for civilian use;


4. Charging at low temperature is actually a micro-short circuit caused by lithium piercing the diaphragm;


5. The aluminum plastic film of the outer packaging is corroded;


6. If the vacuum is not clean, or the mobile phone battery is used in a high altitude environment, the mobile phone batteries are all soft packaging, which has a great impact.

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Why Do LiPo Batteries Swell Up And What Are The Causes?

Is a swollen battery dangerous?

Simply put, yes. It is generally not recommended to continue using a swollen LiPo battery, although it is still possible to use a few more times until you get a replacement. Special care must be taken when charging a swollen LiPo battery. If possible, have it charged away from flammable materials or in a fire-proof container. A swollen LiPo battery is also particularly sensitive to mechanical failure of the casing, so avoid tampering or any type of impact that will pierce, dent or damage the battery. If you really must, use that swollen LiPo battery, then go for it at your own risk. As long as you’re careful, it should be fine. However, you should be looking for a replacement as soon as your battery starts to show any swelling. It will only get worse over time, and you can only push your luck so much.

What causes a LiPo battery to swell?

To understand why a LiPo battery (or any other battery, for that matter) swells, we need to understand how its individual components interact to make the battery work. All batteries are made with three basic components: a negative end, a positive end, and an electrolyte solution. Batteries conduct electricity via the migration of ions from the positive end to the negative end and vice-versa. These ions can travel through the electrolyte solution. LiPo batteries are distinct from the old-fashioned lithium-ion batteries due to their use of a solid polymer electrolyte. Through this solid electrolyte, lithium ions can move between the two terminals of a LiPo battery. A LiPo battery also has polymer separator that keeps the positive and negative terminals from coming into contact with each other.

Batteries swell because of the phenomenon of electrolyte decomposition. As its name implies, this is the process where the electrolyte solution decomposes into its individual components. In most cases, these components include oxygen. In the case of LiPo batteries, the polymeric nature of the electrolyte means that they also tend to produce carbon dioxide (CO2) and carbon monoxide (CO) when they decompose. The production of these gases is what causes a LiPo battery to expand and swell. There have been a lot of instances of LiPo batteries catching fire while they are plugged in. The chances of a LiPo battery charging fire is even higher once electrolytic decomposition has kicked in, as the oxygen-rich gases are very flammable, A good practice to follow is once your LiPo battery has indicated that the battery is full, disconnect the battery and switch the charger off at the wall, and never leave the battery connected to the charger unattended. One thing to remember about battery swelling is that it cannot be avoided. Electrolyte decomposition is a naturally occurring process, albeit it should be a slow one. However, improper maintenance of the battery can accelerate the decomposition process.

How to deal with bulging and leaking LiFePO4 packs?

Lithium iron phosphate battery packs are widely used. Sometimes lithium-ion battery packs will occur leakage and bulging, and the battery bulge and leakage of liquid. What to do? The correct approach should be to use plastic bags or acid-resistant packaging to isolate the battery pack to a professional battery recycling company.

Lithium iron phosphate battery pack bulging causes.

I. Overcharge leads to the bulge

Overcharging will lead to the lithium atoms in the positive material all running to the harmful material inside, resulting in the original entire grid of the positive pole deformation collapse, which is also an important reason for the decline in the power of lithium-ion batteries. In the process, more and more lithium ions in the negative electrode build up, causing the lithium atoms to grow stump crystals and causing the lithium-ion pack to bulge.

II. Bulging caused by over-discharge

SEI film on the harmful electrode material will appear to protect the use of the material structure is not easy to collapse and can increase the cycle life of the electrode material.SEI film is not static. There will be a slight change in the process of charging and discharging. The important thing is that some organic matter will be reversible changes. Lithium-iron phosphate ion battery over-discharge makes the SEI film reversible break ring, protecting the harmful electrode material after the destruction of SEI makes the damaging electrode material collapse, thus forming a bulge phenomenon.

Third, the lithium iron phosphate battery pack manufacturing level of the problem, the electrode coating is not uniform, and the production process is relatively crude.

Fourth, the violent reaction of the short circuit generates a lot of heat, which in turn leads to the decomposition of the electrolyte vaporization, and the battery will bulge.

Lithium iron phosphate battery pack bulge solution

1, please do not continue to use a bulging lithium-iron-phosphate battery pack. Try to replace the new lithium-ion battery pack on time in a bulging situation. Try not to rely on some of the methods taught online to continue to use the battery.

2, usually, do not play with the phone while charging. Regularly adhere to the condition of the battery to avoid dangerous situations.

3, usually, when charging, pay attention to the choice of the charger. For example, the rated charging voltage of the battery is 3.7v, and the limit voltage is 4.2V. As far as possible, do not choose to exceed this voltage charger, can maintain a constant current is best.

4, choose a large manufacturer of lithium iron phosphate battery packs so that the quality is relatively reliable. Necessary, or usually their habits of use on the degree of damage to the battery, should pay more attention.

Lithium iron phosphate battery pack leakage causes

The aging of the sealant leads to cracks in the seal.

Severe overcharging of lithium-ion iron phosphate batteries, mixed-use of different types of lithium-ion battery packs, poor battery gas compounding efficiency.

False leakage is caused by acid splashing out during acid filling.

Usually, the output current is too high, continuous discharge time is too long, and soft pack lithium iron phosphate ion battery temperature rise caused by. Some batteries have been used for a long time at low current and may also leak.

Welding lithium-ion battery pack shell and cap, welding is not solid, not sealed. There is leakage, false welding, welding seams have cracks, cracks, and other problems.

The positive riveting of the cap is not tight, there is a gap, and the elasticity of the insulating gasket is not suitable, not resistant to corrosion, and easy to age.

What can I do about leaking LiFePO4 battery packs?

1, these batteries will be scrapped.

2, the lithium iron phosphate battery leakage sold to the recycling of battery business

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