The electrolyte of valve regulated lead acid battery is in a lean state, that is, most of the electrolyte is adsorbed in the superfine glass fiber membrane, and the rest is absorbed by the electrode plate. In order to ensure that oxygen can diffuse to the negative electrode smoothly, the active substances of the membrane and electrode plate are required not to be saturated by the electrolyte, otherwise it will block the oxygen passage through the membrane, affecting the reduction of oxygen on the negative electrode. In order to make the chemical reaction go on normally, the active substance on the electrode plate must be fully contacted with the electrolyte, while the battery with electrolyte poor structure can only achieve this purpose by tight assembly.

Absorbing glass fiber separator (AGM separator) is an important part of valve regulated lead-acid battery. Its performance and dosage directly affect the technical performance of the battery, especially the service life of the battery.