## 1 Introduction  
Nowadays alternative energy source technologies have attracted great attention, due the depletion of fossil fuels and the consequences that combustion gases have upon global warming. The excessive use of fossil fuels has a large impact in the environment and poses a great risk for human health. Over the last decades, several research groups have focused their efforts on developing new alternative energy sources, such as solar cells [1], wind power [2], biogas [3], marine energy [4] and electrochemical cells [5]. These latter, particularly the electrolyzer and hydrogen fuel cells, are considered to be the main alternatives to fossil fuels used in automobiles [6; 7; 8]. Depending on the membrane type, electrochemical cells can be classified as: Proton exchange membrane fuel cells (PEMFC), alkaline fuel cells (AFC), phosphoric acid fuel cells (PAFC), molten carbonate fuel cells (MCFC) and solid oxide fuel cells (SOFC) [9]. PEMFC are considered an important prospect, since the temperature required for energy production is within 25-100 \({}^{\circ}\)C [10]. The amount of reagents, products and residues generatedfrom electrolyzer and hydrogen fuel cells is much less compared to that produced by other energy sources. Furthermore, components used in these cells are simple and robust, as shown in Figure 1.  
During energy production the membrane is deemed to play a very important role in the efficiency of the electrochemical cell, as it is responsible for separating the electrodes and allowing the free flow of H\({}^{+}\) ions between the anode and the cathode [11]. The membrane consists of a film that contains adequate functional groups that allow ion exchange, for example (-COOH, -SO\({}_{3}\)H) [12]. Perfluorosulfonic acid-type membranes (Nafion) are commonly used in PEMFC applications. Nafion membranes have been demonstrated to have high proton conductivity, flexibility and excellent chemical and mechanical stability in their soaked state [13]. Over the past few years, Nafion has been used in direct ethanol and methanol fuel cells, hydrogen cells and electrolyzer cells [14]. The main drawbacks of Nafion membranes are their methanol permeability, high cost and loss of proton conductivity at approximately 100 \({}^{\circ}\)C [15]. In this respect, some modifications with graphene oxide have been made, but it was discovered that these hybrid membranes could not replace Nafion membranes completely [16]. Other studies have been proposed, with inorganic membranes and bio-membranes obtaining similar performances to the Nafion membrane [17; 18]. In recent years different authors have characterized and assessed the efficiency of membranes through different techniques such as impedance spectroscopy (Nyquist diagram). The resistance of membrane pores is associated with their ionic conductivity, so at a lower resistance the membrane will offer better efficiency [19; 20]. Different comparisons of new membranes to existing ones have also been made, and this has simultaneously led to the development of innovative fuel and electrolytic cells [21; 22]. _Agave salimana_ is an arid and semi-arid plant commonly found in Mexico; it can survive extreme conditions, thanks to its cuticle. The cuticle epidermis is mainly responsible for gas exchanging through stomata, which allows the cuticle to act as an interface between the cell and the external environment [23]. Some researches have used the agave plant with different purposes, for instance bioethanol production [24], as an additive in cement mortars [25], bio-polymer composite formation [26], etc. The chemical characterization of the _Agave salimana_ cuticle has demonstrated the presence of -OH and -COOH functional groups [27; 28; 29]. Figure 1: Components of electrochemical cells. (**a**) Electrolyzer cell (electrolyte) and (**b**) hydrogen cell (galvanic cell). For bio-membranes, ion mobility activation processes are required because this step negatively affects the efficiency of the electrochemical cell.