The Internet of Things (IoT) depends on microscale sensors and devices, which require advanced miniaturized energy storage solutions to power wearables and implants. Recent advances in energy-storage device manufacturing and chemistry have established microbatteries and microsupercapacitors as primary power sources for portable electronics and smart sensors. The introduction of innovative materials and manufacturing techniques, including 3D printing and laser scribing, has facilitated the development of microscale devices with enhanced mechanical and electrochemical properties. 

This thesis introduces a hybrid in-plane microsupercapacitor for self-powered microscale sensors, featuring a Ti3C2Tx MXene negative electrode and a Hex-Aza-COF3 positive electrode, supported by three-dimensional laser-scribed graphene. This design achieves a maximum areal capacitance of 131.46 mF/cm² and an energy density of 12.13 μWh/cm², outperforming carbon-based alternatives, though still trailing microbatteries. To address energy density limitations, 3D printing and Prussian blue electrodes are recommended. 

A subsequent study demonstrates in-plane microsupercapacitors using 3D-printed MXene and Prussian blue, enabled by porous laser-scribed graphene collectors. These devices attain a mass loading of ~30 mg/cm², an areal capacitance of 282.7 mF/cm², and an energy density of 88.34 μWh/cm², representing the highest performance among hybrid microsupercapacitors and highlighting their potential for self-powered sensor applications. 

Moreover, a hybrid zinc-lithium-ion microbattery is proposed, optimized for stable operation across diverse environments. Employing lithium iron phosphate cathodes and a eutectic electrolyte, these batteries deliver reliable performance at both room and elevated temperatures, achieving 260 μAh/cm² at 0.01 mA/cm² at room temperature and 230 μAh/cm² at elevated temperatures. 

Overall, this work advances the design and manufacturing of hybrid in-plane microsupercapacitors and microbatteries, offering practical, high-performance energy storage solutions for future IoT and sensor applications.