Preparation and Properties of EAA Macromolecular Solid Electrolyte

(Department of Chemistry, Nanjing University, Nanjing 210093, Jiangsu, China) A new type of polymer solid electrolyte was prepared. The composition, mechanical properties and electrical conductivity of the system were studied using infrared, dynamic viscoelastic spectrometers and electrochemical impedance spectroscopy.

The equivalent circuit.

In the equivalent circuit, Rg is the bulk resistance of the sample, Rb, Cb are the resistance and capacitance of the crystal phase of the system, R'BC'B is the resistance and capacitance of the amorphous phase of the system, and Ce is the electric double layer capacitance of the electrode and the electrolyte. . The AC impedance spectrum of the EAA polyelectrolyte system can be well explained. The solid line in the curve is a fitting curve. It can be seen that the experimental data fit well with the theoretical curve. The three intersection points of the two semicircles and the real axis are Rg, Rg+Rb (or Rg+R,), and Rg+RB+RB, respectively, from high frequency to low frequency. (Rg+Rb+RB) is the bulk resistance of the system. Expressed by R, the ionic conductivity U) of the system can be calculated by the following equation: Generally speaking, the ionic conductivity of the electrolyte system is proportional to the number of carriers and their mobility. The relationship between the ionic conductivity and the LiCl4 salt content of the EAA polymer electrolyte system, the conductivity of the system increases with the increase of the salt concentration, due to the addition of the LCl4 salt, the salt enters into the amorphous phase, resulting in amorphous content in the system. The ionic conductivity of the system is mainly caused by the migration of U+ ions in the amorphous phase, which leads to an increase in the ionic conductivity of the system. The room temperature ionic conductivity of the system reaches a maximum of 9X106S°cm1, which has a certain application. prospect.

The relationship between the ionic conductivity of EAA polymer electrolyte and the content of LiCl4 salt (Temperature: 298K) 5 Compared with the proposed ECO/NBR two-phase system, the room temperature ionic conductivity of EAA polymer solid electrolyte is not high, mainly because: ECO/ The conductivity of NBR two-phase system is completed by the ECO phase doped with LiCl4. The ECO contains (CH2CH2) n segments, which can coordinate with Li+ and dissociate LiCl4 from Li+. The EAA polymer solid electrolyte system in this paper is conductive EAA. Amorphous carboxyl dimer segments of the copolymer are partially completed, because the segmental motion performance is worse than that of EC, and can be seen from the Tg temperature of both (EC Tg is about 40C and EAA Tg is higher than room temperature) Therefore, the ionic conductivity of the system is lower. Therefore, the solid polymer electrolyte must meet the requirements of industrial applications and the two-phase system has a promising future.

4 Conclusions This work produced EAA polymer electrolytes, which are a two-phase structure: PE crystal phase and amorphous phase formed by carboxy dimer and salt. The ion conduction of the system is mainly accomplished by the amorphous phase. Room temperature ionic conductivity reaches a maximum of 9X106Scm, which has a certain application prospect.