Abstract:
This paper, taking graphene (Gen), conductive carbon black Super-P (SP) and a composite conductive agent consisting of graphene and conductive carbon black (Gen/SP) as the research object, made pouch batteries using a single conductive agent (SP or Gen) and composite conductive agent Gen/SP under different mass ratios, respectively. The cathode material for pouch batteries is LiNi
0.5Co
0.2Mn
0.3O
2, and the preparation process includes preparing slurry, coating, winding, etc. Such testing methods as XRD, SEM and constant-current charging/discharging were applied to study the composites between the conductive agent and positive electrode particles and their effect on the performance of batteries. According to the results, batteries with 1.0% composite conductive agent presented the best performance, and the worst performance was with 0.5% composite conductive agent. Batteries with different contents of composite conductive agent showed better performance, and the pouch batteries prepared with a 1.0% composite conductive agent Gen/SP(5∶5, (
w/
w)) had the best performance. The specific capacity of initial discharge at 0.1 C was 160.38 mA·h/g, while the capacity retention rate was 97.3% after 100 cycles at 0.5 C.