At present, there are more and more manufacturers of flexible power battery in the lithium battery industry, and the size is becoming larger and larger. The test and research of flexible battery is also increasing with the rise of flexible battery. Edge voltage test is also increasingly applied to battery production lines. Today, let's understand how the lower voltage is formed

The voltage of the aluminum layer between the positive ear and the aluminum-plastic film, and the voltage of the aluminum layer between the pole ear and the aluminum-plastic film should be 0v theoretically, because the aluminum layer between them and the aluminum-plastic film is insulated, regardless of the positive or negative pole. In fact, considering that the battery material and its processing process will cause local damage, leading to local conduction between them to form a "micro battery", resulting in potential difference (voltage). The higher the voltage is, the higher the potential risk of the battery is, and the voltage standards vary from manufacturer to manufacturer. Most of the industry is set below 1.0V.

First, understand what the perfect battery should look like in theory:

The ideal state of the flexible battery is as follows: the aluminum plastic film and the positive and negative electrodes are completely insulated through the plastic film, and there is no direct electrical connection between the positive and negative electrodes and the aluminum layer of the aluminum plastic film:

However, there are few perfect batteries in actual production, which is our common battery

When the plastic film is slightly damaged, causing a slight circuit between the negative electrode and the aluminum film, a "micro battery" is formed between the aluminum film and the electrode ear. When testing the voltage between the positive electrode and the aluminum film, a slight small voltage leaked due to poor insulation between the negative electrode and the aluminum film will be measured:

Finally, we will introduce what kind of battery with high side voltage looks like.

When the plastic film is seriously damaged and a reliable circuit is formed between the negative electrode and the aluminum film, test the voltage between the positive electrode and the aluminum film, that is, the actual voltage between the positive electrode and the negative electrode: