Highly conductive and mechanically robust composite cathodes based on 3D interconnected elastomeric networks for deformable lithium‐ion batteries
Sung Hyuk Park,
Yong Woon Lee,
Da Eun Kim,
Kyung Gook Cho,
Min Su Kim,
Dong Hyun Park,
Junyoung Mun,
Keun Hyung Lee
Affiliations
Sung Hyuk Park
Department of Chemistry and Chemical Engineering, Education and Research Center for Smart Energy and Materials Inha University Incheon Republic of Korea
Yong Woon Lee
Department of Chemistry and Chemical Engineering, Education and Research Center for Smart Energy and Materials Inha University Incheon Republic of Korea
Da Eun Kim
Department of Chemistry and Chemical Engineering, Education and Research Center for Smart Energy and Materials Inha University Incheon Republic of Korea
Kyung Gook Cho
Department of Chemistry and Chemical Engineering, Education and Research Center for Smart Energy and Materials Inha University Incheon Republic of Korea
Min Su Kim
Department of Chemistry and Chemical Engineering, Education and Research Center for Smart Energy and Materials Inha University Incheon Republic of Korea
Dong Hyun Park
Department of Chemistry and Chemical Engineering, Education and Research Center for Smart Energy and Materials Inha University Incheon Republic of Korea
Junyoung Mun
School of Advanced Materials Science and Engineering, SKKU Institute of Energy Science and Technology (SIEST) Sungkyunkwan University Suwon Republic of Korea
Keun Hyung Lee
Department of Chemistry and Chemical Engineering, Education and Research Center for Smart Energy and Materials Inha University Incheon Republic of Korea
Abstract Deformable lithium‐ion batteries (LIBs) can serve as the main power sources for flexible and wearable electronics owing to their high energy capacity, reliability, and durability. The pivotal role of cathodes in LIB performance necessitates the development of mechanically free‐standing and stretchable cathodes. This study demonstrates a promising strategy to generate deformable cathodes with electrical conductivity by forming 3D interconnected elastomeric networks. Beginning with a physically crosslinked polymer network using poly(vinylidene fluoride‐co‐hexafluoropropylene) and 1‐ethyl‐3‐methylimidazolium bis(trifluoromethylsulfonyl)imide ([EMI][TFSI]), subsequent exchange with a 1 M LiPF6 electrolyte imparts elastic characteristics to the cathodes. The resulting LiFePO4 composite electrodes maintained their resistance under 500 consecutive bending cycles at an extremely small bending radius of 1.8 mm and showed high discharge capacity of 158 mAh g−1 with stable potential plateaus in charging and discharging curves. Moreover, flexible cells utilizing the composite electrodes exhibited superior operational stability under rolling, bending, and folding deformations.
