Journal of Power Sources 434 (2019) 226735 0378-7753/© 2019 Elsevier B.V. All rights reserved. Lifetime assessment of solid-state hybrid supercapacitors based on cotton fabric electrodes A.J. Paleo a, * , P. Staiti b , A.M. Rocha a , G. Squadrito b , F. Lufrano b, ** a 2C2T – Centro de Ci^ encia e Tecnologia T^ extil, Universidade do Minho, Campus de Azur� em, 4800-058, Guimar~ aes, Portugal b CNR-ITAE, Istituto di Tecnologie Avanzate per l’Energia “Nicola Giordano”, 98126, S. Lucia, Messina, Italy HIGHLIGHTS � Hybrid cotton fabric electrodes with MnO 2 and AC by easy processes were developed. � A new assessing method for long-term durability under harsh conditions is analysed. � The use of Aquivion as solid-state electrolyte in SCs is introduced for frst time. � The hybrid solid-state supercapacitors worked with success in a high voltage range. � The supercapacitors showed low self-discharge rates and good specifc capacitances. A R T I C L E INFO Keywords: Carbon nanofber Manganese oxide Solid-state electrolyte Hybrid supercapacitor ABSTRACT Electrodes based on activated carbon and manganese oxide coated on a cotton woven fabric were developed and investigated. The electrodes were then assembled with two polymer electrolyte membranes, Nafon ® 115 and Aquivion®E87-05S, and two different supercapacitors were produced with specifc capacitances and energy densities of 130 and 132 F g 1 , and 11.5 and 11.7 Wh kg 1 , respectively. Furthermore, a new durability meth- odology, which combines galvanostatic charge/discharge cycles together with potentiostatic foating conditions, was used to get insight into their electrochemical performance under stringent conditions. The supercapacitor assembled with Nafon ® 115 electrolyte worked successfully for 10 k cycles and 140 h under a constant voltage of 1.6 V (foating condition), whereas the supercapacitor assembled with Aquivion®E87-05S electrolyte worked successfully for more than 15 k cycles and 210 h, without any appreciable degradation of their electrochemical properties. In summary, hybrid solid-state supercapacitors based on electrodes produced by simple methodol- ogies and low-cost materials, and with long durability performance under very harsh conditions were developed and analysed for their potential utilization as fexible energy storage devices. 1. Introduction At present, batteries and electrochemical capacitors are becoming of primary importance as power supplies of portable electronic systems. However, these devices are rigid and have limited usability in terms of mechanical stability upon bending or stretching for wearable elec- tronics. In this respect, textile fabrics, which are thin fexible sheets of interlaced yarns produced by different technologies such as weaving, knitting, and braiding have additional advantages over other materials owing to their mechanical strength, fexibility properties and absorption and desorption ability (for absorbing and releasing of ions in the solvent) [1], and therefore, fexible energy storage devices based on textile fab- rics, particularly oriented towards the production of supercapacitors (SCs), are a viable alternative to overcome those limitations because of their quick charge-discharge capability, long life and safety. It is generally accepted that energy in SCs is electrostatically stored by accumulated charges on the electrode surface, and electrolyte ions with counterbalancing charge on the electrolyte side, which is denominated as electric double layer capacitance (EDLC) [2]. However, the fabrica- tion of scalable, lightweight and durable textile-based SCs possessing a combination of high capacitance with high power and energy density is still a signifcant challenge [3], and fabric-based electrodes with high * Corresponding author. ** Corresponding author. E-mail addresses: ajpaleovieito@2c2t.uminho.pt (A.J. Paleo), lufrano@itae.cnr.it (F. Lufrano). Contents lists available at ScienceDirect Journal of Power Sources journal homepage: www.elsevier.com/locate/jpowsour https://doi.org/10.1016/j.jpowsour.2019.226735 Received 18 March 2019; Received in revised form 14 May 2019; Accepted 5 June 2019