Long-lasting, flexible and fully bioresorbable AZ31-tungsten batteries for transient, biodegradable electronics

Rapid technological revolution produces a wide range of convenient tools, while, in particular, the production and consumption of batteries lead to various issues including environmental pollution. Although efforts to solve such problems increase interest in green and dissolvable batteries, their short service life is still recognized as a major obstacle due to limited options of materials. Here, we propose materials and system designs for eco-friendly and biodegradable magnesium alloy-tungsten (AZ31-W) batteries that offer long-term stability with enhanced corrosion resistance. Materials and electrochemical inspections confirm the superior electrochemical tolerance and stable, reliable potentials of the AZ31 anode and W cathode. The assembly of an individual cell into a commercially available pouch battery yields a high capacity of ∼430 mA h g⁻¹, suitable for high-energy applications. The integration of alginate-based soft, elastic electrolytes with the electrodes enables the achievement of completely eco-resorbable solid-state batteries that maintain performance under diverse physical deformations. The results suggest potential for biomedical and eco-friendly applications where commercial batteries pose risks to the environment or human body.