Fig. 2. (a) Schematic configuration of the primary Zn–air battery; (b) polarization and power density curves of Zn–air batteries with different electrocatalysts; (c) discharge curves of Zn–air batteries with different electrocatalysts at various current densities; (d) a lamp (3 V; 1 W) powered using three series-connected Zn–air batteries; (e and f) discharge curve of the Zn–air battery with the LaMnO-30 cathode electrocatalyst at (e) 100 mA cm^–2 and (f) 10 mA cm^–2, the arrow in (f) indicates the point where the Zn anode and electrolyte were replaced, ref. 45, copyright© Tsinghua University Press and Springer-Verlag GmbH Germany 2017.