What factors affect the cycle performance of lithium polymer batteries?

Among all the advancements in the battery technology that we use today, Lithium Polymer is some of the best thanks to its wide applications and reliable performance. The lithium polymer battery technology solves several problems that we had with the previous battery technologies, but for the best application and stability, a reliable cycle performance is essential.

Although these batteries already perform extremely well, there are a few factors that can affect the cycle performance, and that can impact the longevity and effectiveness of these batteries. So, in this article, we will highlight some factors that can impact the lithium polymer battery cycle performance.

Raw Material

It is not only true about the lithium polymer battery technology, but the raw material quality can impact the performance and life of any battery technology. It is because there are multiple raw materials used in the composition of a battery, and each one has a different role, as explained below.

Quality of Lithium Polymers

Starting with the quality of lithium polymers. This quality is pivotal in determining both the high-performing capabilities of your battery as well as the longevity of the battery. Going with high quality will ensure that the ionic conductivity of electrolytes is augmented but also increase the safety rating of the battery since the chances of any unwanted disaster from the battery are reduced. It is because the purity increases the battery's resistance to extreme conditions.

Choices of cathode and anode materials

The cathode and anode materials play an important role in the operation of the battery. It is because these connect the external load with the internal components of the battery. The material can impact the cycle performance of lithium polymer batteries with the following factors:

Energy density

Thermal stability

Cost

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When selecting these materials, the main qualities to look for are performance and safety to ensure that these batteries can be widely applicable.

Composition of Electrolytes in the Battery

Lithium polymer batteries can't perform without an electrolyte in them. The electrolyte works as a bridge for the flow of electrons between the positive and negative materials. It means that if the electrolyte composition is not top quality, the performance, capacity to store power, and longevity, all qualities of the battery will be downgraded.

Positive and Negative Electrode Compaction

Electrode compaction is one of the innovations for the lithium polymer battery technology, and it needs to be extremely precise. It is because it can improve the efficiency of your battery in multiple ways, including energy density and thermal management when the battery is operational.

Impact of Compaction on Energy Density

Energy density, in easier words, is the amount of energy a battery can store regarding its total volume. Electrode compaction has a huge role here since tighter compaction means that the battery can store more energy, making its energy density higher. It is a key factor for applications that require compact and lightweight batteries yet require reasonable power with a good flow of electrons.

However, the compaction needs to be done while maintaining balance since overdoing it may become a roadblock for performance.

Impact on Thermal Management for the Battery

Most battery applications today require batteries to provide a lot of power in a very short time, and that can produce heat. That’s why thermal management is important since it keeps the battery performing safely and reliably. The electrode compaction determines how efficiently the electrode will take heat away from the battery cell, making it safer to operate. Along with compaction, the electrode material's thermal conductivity also has high importance here.

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Importance of Consistency in Electrode Compaction

The electrode compaction consistency tells how uniform battery operation will be through its lifespan under different circumstances and how long it will last. When electrode compaction is done uniformly while maintaining industrial standards, every cell gets the same stress while operating, and this uniform stress distribution protects the battery from excessive premature degradation.

Water Content

Water is usually not a part of the lithium polymer batteries since these commonly don’t come with a liquid electrolyte like lead acid batteries. However, if you find water inside the battery, it will have its fair share of impacting the cycle performance of the battery in multiple ways, as explained below:

Impact of Water Content on Electrolyte Stability

The first-way water content in your lithium polymer battery will negatively impact the battery cycle performance is by making the electrolyte unstable. Even if there is a minute amount of water in the electrolyte, it can make the flow of electrons through the electrolyte less effective, and that can build up pressure on the cell. That pressure often causes gas production in the battery, leading it to become less structurally secure. So, not only does it decrease performance, but it also increases safety concerns.

Impact on the Degradation and Corrosion of Electrodes

Water content around the battery cells, especially in the electrode region, can cause major issues like degradation and corrosion. It usually happens at the anode since the water molecules instigate unwanted side reactions with it. When corrosion forms, the connection between the battery cell and the load becomes inefficient. This corrosion does not stop here since it constantly eats away the electrode material, hurting the performance and longevity of the battery.

Other Safety and Longevity Concerns

Apart from the impact of water content on electrodes and electrolytes, it has several other concerns when it comes to safety and longevity. For example, water can lead to internal short circuits in the battery. It can also cause corrosion inside the battery cell or at some connection point apart from the electrode that will gradually cause degradation of that part.

Conclusion

Although lithium polymer batteries are among the most widely applicable and reliable batteries under different circumstances, there still are several factors that, if ignored, will severely impact the cycle performance of these batteries. These factors start from the raw materials used for making the battery and include the usage principles for the battery. By unveiling these factors, their impact, and details, we can be more aware of how we can save our lithium polymer batteries by changing their design or usage practices.