Effect Of Water Binder On The Electrochemical Performance Of Graphite

Lithium-ion battery research began in the 1980s. Early 1990s,the first generation of lithium battery is produced by Sony. Commercialization of Lithium-ion battery became available. Lithium-ion battery are characterized by a high energy density, high voltage(3.6v), small volume and quality, good cycle performance. Lithium-ion battery are popular. In thirty years, lithium battery has been applied extensively in computer, cell phone, and many other portable electronic products. In the future, it will be applied in hybrid cars.The key materials of Lithium-ion battery include anode/cathode material, electrolytes and collector, etc. Binders are the auxiliary material for lithium-ion battery. Though it is only used for the mixing of active materials and coating onto a collector, but it influence the performance of cell largly. At present, the binders include: PVA, PTFE, CMC,TPE, SBR, PVDF and so on. PVDF is widely used in the batteries industry. However it react easily with lithium metal and lithiated graphite (LixC6) to form more stabe LiF and >C=CF- double bonds. Furthermore, these reactions release a lot of reat. So it is bad for the batteries'safety.In this paper we mainly study the effect of water binder on the electrochemical performance of graphite. The effect of water binder such as Sodium alginate, Polygalacturonic acid sodium salt, Deerhorn glue on the electrochemical performance of graphite was investigated and were compared each other by constant current discharge, CV, SEM and FTIR. The main conclusions of the experiment follows:(1) We use Sodium alginate, Polygalacturonic acid sodium salt and Deerhorn glue as wate binder of graphite. The graphite electrodes bonded by Sodium alginate has good performance. The graphite electrodes bonded Polygalacturonic acid sodium salt have good first charge/discharge inefficient.(2) Using Sodium alginate, alginate lithium and alginate potassium as water binder of graphite, the graphite bonded Sodium alginate still indicates better electrochemical performance in comparison to the others.(3) Using Polygalacturonic acid lithium salt, Polygalacturonic acid sodium salt and Polygalacturonic acid potassium salt as water binder of graphite, the graphite bonded Polygalacturonic acid sodium salt has better performance than others.(4) In compareison to PVDF, Sodium alginate has a similar performance in the first delithiation capacities and inefficient as the conventional PVDF. But the PVDF has better rate performance.