A large-size, bipolar-stacked and high-safety solid-state lithium battery with integrated electrolyte and cathode

A large-size, bipolar-stacked and high-safety solid-state lithium battery with integrated electrolyte and cathode is fabricated conveniently via solvent-free UV-cure. Firstly, a series of new solid polymer electrolytes are synthesized through UV-cure, and exhibit a maximum conductivity of 1.29 × 10−4 S cm−1 (60 °C), a wide electrochemical window (0–5.1 V) and excellent compatibility with Li. Secondly, solid-state LiFePO4/Li cell with integrated electrolyte and electrode is fabricated and delivers a high capacity of 113.3 mAh g−1 after the 100th cycle, and the capacity retention is 90.2%. The outstanding cell performance is ascribed to the integrated electrolyte/cathode design which is beneficial for the interfacial impedance decreasing. Finally, a 5 cm × 8 cm size battery with integrated electrolyte/cathode is assembled conveniently, and it presents the 80.55% retention of discharge capacity at the 200th cycle and high-safety. It can be well work under the conditions of bending, cutting, on the fire and even after nail penetration. Remarkably, the bipolar-stacked battery is also fabricated, and the open circuit voltage is as high as 6.33 V. Consequently, this work develops a series of new solid polymer electrolytes and proposes an advanced cell construction design for solid-state lithium batteries which is very suitable for the large-scale preparation.