It is important to note that battery packs in certain applications may be exposed to corrosive elements such as acidic substances, salt, and sometimes conductive substances and liquids. Over time, this exposure will slowly corrode PCBA, components and solder joints. This type of corrosion can lead to premature failures, short circuits and dangerous situations that can lead to fires or even explosions.

What is a conformal coating?

Conformal coating is a protective chemical coating or polymer film with a thickness of 25-75μm (typical value is 50μm), which conforms to the circuit board topology. Circuit board conformal coatings are designed to protect electronic circuits from harsh environments that may contain moisture and chemical contaminants.

Common uses of conformal coatings

Conformal coating is a method commonly used to seal or prevent corrosion and other damage caused by external contaminants that come into contact with electronic components over time. The battery pack can also be used in applications where high humidity is the main factor. Most enclosures are designed to prevent contaminants, but there is always the possibility of moisture, especially in tropical or humid climates.

Conformal coatings can also be used to withstand higher electric fields in high component density designs. As an advantage, due to the insulating effect of the coating, the design of a higher voltage battery pack can be made smaller. PCB conformal coatings are usually sprayed on circuit boards and components (or when thicker coatings are required, sometimes brushed or dipped). This will form a non-conductive seal between the component and the circuit board. When the application requires the battery pack to perform or is exposed under adverse conditions, the seal will prevent the electronic circuit from being damaged.

Conformal coating process for battery pack

FASTPCBA SMT manufacturer: The usual operating sequence is to first test the function of the filled circuit board, and then tape or cover the areas that do not need coating. If the application allows it, it can be done using temporary templates or basic tapes. Then spray the coating at a uniform thickness and wait until it is dry. Once the PCBA is coated and dried, the battery pack can be installed and the final assembly can be completed. The completed battery pack can now be sent to the final packaging level test step, confirmed, packaged and shipped to the customer.