Anticorrosive flexible pyrolytic polyimide graphite film as a cathode current collector in lithium bis(trifluoromethane sulfonyl) imide electrolyte

Abstract

a b s t r a c t a r t i c l e i n f oFlexible pyrolytic polyimide graphite film (PGF) is explored as a cathode current collector in lithium ion batteries using lithium bis(trifluoromethane sulfonyl) imide (LiTFSI) based electrolyte. It is demonstrated that no obvious anodic current is observed up to 4.5 V versus Li + /Li for PGF, while significant corrosion current is found from 3.6 V for aluminum, indicative of better electrochemical stability of PGF than that of aluminum in LiTFSI based electrolyte. LiMn 2 O 4 on aluminum and PGF has been used as model electrode for testing. There is hardly any capacity retained after 10 cycles at room temperature for the LiMn 2 O 4 /aluminum electrode. With regard to the LiMn 2 O 4 /PGF electrode, the capacity retention ratio remained 89% after 1000 cycles. Moreover, at an elevated temperature of 55°C, the capacity retention ratio kept at 81% after 300 cycles. Since LiTFSI-based electrolyte shows advantages in safety, stability and conductivity but could not be used due to Al-corrosion, the application of the PGF current collector could overcome this barrier.

Flexible graphite film with laser drilling pores as novel integrated anode free of metal current collector for sodium ion battery

“…Flexible polyimide graphite films possess a highly in-plane oriented structure [16], which endows the graphite film with excellent planar electrical conductivity and considerable mechanical strength. By laser drilling pores on the graphite films, more intercalation channels were obtained to improve the kinetics.…”

Review on carbonaceous materials and metal composites in deformable electrodes for flexible lithium-ion batteries

“…Aerward, LiMn 2 O 4 cathode active materials are grown on exible graphite current collector. 149 In addition, graphite lm with active materials possess extreme exibility that can be rolled up and could be altered into a variety of shapes as well as sizes enabling cell design exibility. Moreover, the cathode exhibits a high discharge capacity (135 mA h g À1 at 0.2C), and outstanding cycle life (89% capacity retentions aer 1000 cycles at 0.5C), and also retained 81% capacity over 300 cycles even when temperature raised up to 55 C. On the contrary, in the case of the aluminum-based current collector, the LMO/Al cathode is completely contaminated aer a few cycles.…”

“…16 Cui et al reported that with respect to pyrolytic graphite lm, Al current collector rapidly contaminated in lithium bis(triuoromethane sulfonyl)imide electrolyte containing system when temperature rises to 55 C. Also, PGF based electrode possesses a greater degree of exibility than that of Albased electrode. 149 From the abovementioned discussion, we can assume that carbonaceous materials are highly reliable for the fabrication of pliable and stable electrodes for FLIBs.…”

“…Also, PGF based electrode possesses a greater degree of flexibility than that of Al-based electrode. 149 From the abovementioned discussion, we can assume that carbonaceous materials are highly reliable for the fabrication of pliable and stable electrodes for FLIBs.…”

A novel electrolyte additive for improving the interfacial stability of LiMn2O4 cathode lithium-ion batteries at elevated temperature

“… 14 Some new lithium salts, such as LiTFSI, LiFAP, and LiBETI, with properties superior to those of LiPF 6 have been evaluated. 15,16 However, the new lithium salts due to some of their own drawbacks have not fully replaced LiPF 6 in LiMn 2 O 4 -based batteries in recent years.…”