Research progress in electrochemical properties of lithium batteries with PAA binders

Electrode binder is an essential part to maintain the integrity of electrode, and it is very important to improve the specific capacity and cycle stability of the battery. Polyacrylic acid (PAA) is widely used as the binder of anode or cathode in the lithium batteries because it contains more polar functional groups and can be dissolved in water. Due to possessing a lot of polar groups, PAA binder has better adhesion. But the hydrogen bond formed between the molecular chains by polar groups makes the PAA molecular chain more rigid, which is not conducive to maintaining the integrity of the electrodes during charging and discharging. It indicates that controlling the number of PAA functional groups and changing the type of functional groups/molecular chain structure of PAA binder have a great influence on the improvement of battery performance. The effect of PAA binder on electrochemical performance of lithium battery in recent years was reviewed in this paper, focusing on the structural characteristics, modification and application methods and their effects on the initial coulombic efficiency, cycling stability and impedance of different lithium batteries. Perspectives on the future of modified PAA binder were reviewed. The effects on the performance of the binder were explored after introducing different structures such as elastic or conductive groups. Improving the interface performance is to be suitable for cathode and anode with different active materials, and to improve the lithium ion diffusion coefficient. Then the performance of lithium battery is also enhanced.