Voltammetric Priming for Electrochemically Stable 3D Printed Aqueous Gel Li-ion Rechargeable Batteries in Various Form Factors

Rechargeable batteries with customizable shapes and geometries that can be incorporated directly into the design of a device by 3D printing of functional materials could enable new smart devices for consumer electronics, medical devices, and connected living technologies. We report a 3D printing approach to a non-flammable all-plastic battery construction that operates as an aqueous Li-ion rechargeable battery. The battery cell is made using an extruder-type 3D printing method for the cell architecture, including graphene-impregnated conductive polylactic acid (PLA) current collectors within an acrylonitrile butadiene styrene (ABS) plastic cell, and an aqueous LiNO₃-containing polyvinylpyrrolidone-silica gel electrolyte for the cell chemistry, without any separator. LiCoO₂ cathodes and LiMn₂O₄ anode materials uniformly coated PLA current collectors allow operation within the water electrolysis window. These printed batteries exhibit good specific capacities of between 30 mAh g⁻¹ (1 C) to 90 mAh g⁻¹ (0.1 C) for at least 100 charge/discharge cycles, and gravimetric and volumetric energy densities of ∼110 Wh kg⁻¹ and 0.33 Wh L⁻¹, following a voltammetric priming step to enhance electrochemical stability during cycling. 3D printed cells can be printed to 4 mm thickness, as a donut-shaped rechargeable Li-ion battery, or as LEGO-brick series connections .