본 연구는 경상남도 지역 내 치유농장 운영 실태를 조사하여 향후 경남지역에 적합한 치유농장 운영과 프로그램 개발을 위한 기초 자료를 제공하기 위해 수행되었다. 조사 결과, 37개 치유농장 중 62.1%는 기존에 교육농장, 사회적 농업 거점농장, 농가 맛집, 체험농장 등으로 운영되다가 3년 전부터 치유농업을 도입하여 현재 다양한 형태로 운영되고 있는 것으로 나타났다. 치유농장 시설의 경우, 숙박시설이 있는 농가는 40.5%, 예약제로만 운영되는 농가는 59.5%, 장애인을 위한 편의시설이 마련된 농가는 48.6%로 나타났다. 또한, 응급 처치 및 안전 관련 용품은 100%의 농가에서 비치하고 있었고, 치유농장 홍보는 SNS와 온라인을 이용하는 농가가 84.1%로 가장 많았다. 예방 중심형 치유 프로그램을 운영하는 농가는 76.2%였고, 개인보다 단체 참여 비율이 86.3%로 높게 나타났다. 치유 프로그램 운영자는 치유농업사 양성기관 교육을 이수하거나 치유농업 시설 운영자 교육 이수자 또는 치유농업사 자격 소지의 농장 경영주가 59.6%로 가장 많았으며, 1회당 참여 인원은 11명에서 20명까지가 43.2%, 1회당 운영 시간은 120분이 51.4%, 참가 비용은 1만원에서 3만원까지가 71.3%로 가장 많은 비중을 차지했다. 활용 자원으로는 식물 자원이 48.6%, 농촌 환경 문화 자원이 39.2%, 동물 및 곤충 자원이 12.2%로 나타났다. 프로그램 운영에 있어 치유농장 운영자의 전문성은 4.48점으로 가장 높았고, 치유농장 자원 중 환경 자원은 4.37점, 편의시설은 쾌적하고 청결한 환경 4.13점, 기타 부가서비스는 농장의 신뢰성이 4.45점으로 가장 중요한 요소로 평가되었다. 효율적인 치유농장 운영에 있어 치유농장 운영자의 전문성, 친밀감·편안한 분위기, 자연경관, 편안하고 안락한 시설, 농장의 신뢰성 요소는 서로 상관관계(p<.05)가 있는 것으로 나타났다.
In zinc-air batteries, the gel polymer electrolyte (GPE) is an important factor for improving performance. The rigid physical properties of polyvinyl alcohol reduce ionic conductivity, which degrades the performance of the batteries. Zinc acetate is an effective additive that can increase ionic conductivity by weakening the bonding structure of polyvinyl alcohol. In this study, polymer electrolytes were prepared by mixing polyvinyl alcohol and zinc acetate dihydride. The material properties of the prepared polymer electrolytes were analyzed by Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), X-ray diffraction (XRD), and thermogravimetric analysis (TGA). Also, Electrochemical impedance spectroscopy was used to calculate ionic conductivity. The electrolyte resistances of GPE, 0.2 GPE, 0.4 GPE, and 0.6 GPE were 0.394, 0.338, 0.290, and 0.213 Ω, respectively. In addition, 0.6 GPE delivered 0.023 S/cm high ionic conductivity. Among all of the polymer electrolytes tested, 0.6 GPE showed enhanced cycle life performance and the highest specific discharge capacity of 11.73 mAh/cm2 at 10 mA. These results verified that 0.6 GPE improves the performance of zinc-air batteries.
Flexible zinc-air batteries have many merits, including low cost, high safety, environmentally friendliness applicability, etc. One of the key factors to improve the performance of flexible zinc-air batteries is to use a gel electrolyte. In this study, gel electrolytes were synthesized from potato, sweet potato, and corn starch. In a comparison of each starch, the corn starch-based gel electrolyte showed the highest discharge capacity of 12.41 mAh/cm2 in 20 mA and 6.47 mAh/cm2 in 30 mA. It also delivered a higher specific discharge capacity of 7.06 mAh/cm2 than the other materials after 100° bending. In addition, the electrochemical impedance spectroscopy (EIS) was analyzed to calculate the ionic conductivity. The potato, sweet potato, and corn starch-based gel electrolytes showed electrolyte resistances (Re) of 0.306, 0.298, and 0.207 Ω, respectively. In addition, the corn starch-based gel electrolyte delivered the highest ionic conductivity of 0.121 S cm-1 among the other gel electrolytes. Thus, the corn starch-based gel electrolyte was verified to improve the performance of flexible zinc-air batteries
For zinc-air batteries, there are several limitations associated with zinc anodes. The self-discharge behavior of zincair batteries is a critical issue that is induced by corrosion reaction and hydrogen evolution reaction (HER) of zinc anodes. Aluminum and indium are effective additives for controlling the hydrogen evolution reaction as well as the corrosion reaction. To enhance the electrochemical performances of zinc-air batteries, mechanically alloyed Zn-Al and Zn-In materials with different compositions are successfully fabricated at 500rpm and 5h milling time. Investigated materials are characterized by X-ray diffractometer (XRD), field emission scanning electron microscope (FE-SEM), and energy dispersive spectrometer (EDS). Alloys are investigated for the application as novel anodes in zinc-air batteries. Especially, the material with 3 wt% of indium (ZI3) delivers 445.37 mAh/g and 408.52 mAh/g of specific discharge capacity with 1 h and 6 h storage, respectively. Also, it shows 91.72 % capacity retention and has the lowest value of corrosion current density among attempted materials.
A zinc-air battery consists of a zinc anode, an air cathode, an electrolyte, and a separator. The active material of the positive electrode is oxygen contained in the ambient air. Therefore, zinc-air batteries have an open cell configuration. The external condition is one of the main factors for zinc-air batteries. One of the most important external conditions is temperature. To confirm the effect of temperature on the electrochemical properties of zinc-air batteries, we perform various analyses under different temperatures. Under 60 oC condition, the zinc-air cell shows an 84.98 % self-discharge rate. In addition, high corrosion rate and electrolyte evaporation rate are achieved at 60 oC. Among the cells stored at various temperature conditions, the cell stored at 50 oC delivers the highest discharge capacity; it also shows the highest self-discharge rate (65.33 %). On the other hand, the cell stored at 30 oC shows only 2.28 % self-discharge rate.
A zinc-air battery is one of most promising advanced batteries due to its high specific energy density, low cost, and environmental friendliness. However, zinc anodes in zinc-air batteries lead to several issues including self-discharge, corrosion reaction, and hydrogen evolution reaction (HER). In this paper, viscosity of electrolyte has been controlled to suppress the corrosion reaction, HER, and self-discharge behavior. Various viscosity average molecular weights of poly(acrylic acid) (PAA) are adopted to prepare the electrolyte. The evaporation of electrolytes is proportional to the increase in molecular weight. In addition, enhanced self-discharge behavior is obtained when the gelling agent with high molecular weight is used. In addition, the zinc-air cell assembled with lower viscosity average molecular weight of PAA (Mv ~ 450,000) delivers 510.85 mAh/g and 489.30 mAh/g of discharge capacity without storage and with 6 hr storage, respectively. Also, highest capacity retention (95.78 %) is obtained among studied materials.
The self-discharge behavior of zinc-air batteries is a critical issue induced by corrosion and hydrogen evolution reaction (HER) of zinc anode. The corrosion reaction and HER can be controlled by a gelling agent and concentration of potassium hydroxide (KOH) solution. Various concentrations of KOH solution and polyacrylic acid have been used for gel electrolyte. The electrolyte solution is prepared with different concentrations of KOH (6 M, 7 M, 8 M, 9 M). Among studied materials, the cell assembled with 6 M KOH gel electrolyte exhibits the highest specific discharge capacity and poor capacity retention. Whereas, 9 M KOH gel electrolyte shows high capacity retention. However, a large amount of hydrogen gas is evolved with 9 M KOH solution. In general, the increase in concentration is related to ionic conductivity. At concentrations above 7 M, the viscosity increases and the conductivity decreases. As a result, compared to other studied materials, 7 M KOH gel electrolyte is suitable for Zn-air batteries because of its higher capacity retention (92.00 %) and specific discharge capacity (351.80 mAh/g) after 6 hr storage.