Three-dimensional (3D) microbatteries offer an opportunity to provide mobile power at dimensions that are comparable with those of the actuators, sensors, and other internet-connected devices that constitute the internet of things (IoT). To overcome the difficulties of assembling these architectures, we developed an entirely new fabrication route based on semiconductor processing methods. The use of partially lithiated (10% of theoretical capacity) silicon as the negative electrode keeps the volume change suitably controlled so that the Si array registry is maintained during charge and discharge. Photopatterning of SU-8 photoresist creates a conformal solid electrolyte coating around the high-aspect-ratio Si arrays. Rechargeable 3D microbatteries prepared on a 3 mm × 3 mm footprint have an areal capacity of nearly 2 mAh cm⁻², operate at current densities up to 0.66 mA cm⁻², and withstand 100 cycles. The combination of semiconductor-based processing and photopatternable electrolytes holds great promise for the further development of 3D microbatteries for IoT applications.

三维（3D）微型电池提供了以与致动器，传感器和其他构成物联网（IoT）的互联网连接设备相当的尺寸提供移动电源的机会。为了克服组装这些架构的困难，我们基于半导体加工方法开发了一条全新的制造路线。使用部分锂化（理论容量的10％）的硅作为负极可保持适当控制体积变化，以便在充电和放电期间保持Si阵列配准。SU-8光致抗蚀剂的光图案化会在高纵横比Si阵列周围形成共形的固体电解质涂层。在3毫米×3毫米的占地面积上准备的可充电3D微型电池的面积容量接近2 mAh厘米^-2，在高达0.66 mA cm ^-2的电流密度下运行，并可以承受100个循环。基于半导体的处理和可光图案化的电解质的结合为物联网应用的3D微型电池的进一步开发提供了广阔的前景。