This paper describes a study, which proposes an alternative and safe energy source, namely, a flexible aluminium-air battery that is suited for use in special garments and wearable products, particularly those worn by children. The need for such a battery has arisen in our recent study, in which we have developed a textile-circuitbased enuresis alarm system. The system is primarily intended for use by children while they sleep, hence the use of lithium ion or other traditional batteries poses serious safety risks. The proposed battery uses saline electrolyte and all of its elements are flexible, which makes it particularly suitable for use in such specialized arrangements, where the appearance of a physiological or other type of saline electrolyte (urine, sweat, blood) energizes and activates the system. This paper studies constructive particularities of such a battery, arrangement of its components, as well as electrical properties and possible applications in medical and smart childcare products, e.g., the enuresis alarm system, smart diapers etc. Methods of integration of the developed batteries in textile products are described, which are based on our previous experience and studies. The developed battery enables one to replace a split “sensor/processing unit” system with an energy source, which actively reacts to changes in its environment and generates electricity. Low costs of the proposed battery, as well as the availability of its main components, make it perfect for wide range of applications from human and animal care to consumer products.