Superlithiation of non-conductive polyimide toward high-performance lithium-ion batteries

• Published in: Journal of materials chemistry. A, Materials for energy and sustainability Vol. 6; no. 42; pp. 21216 - 21224
• Main Authors: Yang, Haoqi, Liu, Shuwu, Cao, Lihua, Jiang, Shaohua, Hou, Haoqing
• Format: Journal Article
• Language: English
• Published: Cambridge Royal Society of Chemistry 2018
• Subjects: Additives; Carbonyls; Electrical conductivity; Electrical resistivity; Electrodes; Graphene; Lithium; Lithium-ion batteries; Multilayers; Operating temperature; Polyimide resins; Polymers; Rechargeable batteries; Specific capacity
• ISSN: 2050-7488; 2050-7496
• DOI: 10.1039/C8TA05109G

Superlithiation has been observed in some carbonyl-based organic electrodes, which leads to very high battery capacity. However, as typical carbonyl polymers, polyimides (PIs) exhibited a relatively low capacity (≤250 mA h g −1 ) in previous studies because their poor electrical conductivity restricts superlithiation. Therefore, to realize superlithiation, in this study, multilayer graphene (MG) as a conductive additive was incorporated in PI matrix through a blending precipitation and thermal imidization method. As an electrode in lithium-ion batteries, PI–MG exhibited outstanding capacity (612 mA h g −1 at 100 mA g −1 ) and stable long-term cyclability (89.3% capacity retention over 500 cycles at 500 mA g −1 ). Moreover, the battery could be operated stably at various temperatures, and it exhibited very high specific capacity, especially at the high operating temperature of 55 °C (873 mA h g −1 , 0.1C). We believe that this strategy of introducing conductive additives to promote superlithiation is highly applicable to other non-conductive carbonyl polymers for lithium-ion battery applications.