Batteries with conformal shape and multiple functionalities could provide new degrees of freedom in the design of robotic devices. For example, the ability to provide both load bearing and energy storage can increase the payload and extend the operational range for robots. However, realizing these kinds of structural power devices requires the development of materials with suitable mechanical and ion transport properties. Here, we report biomimetic aramid nanofibers–based composites with cartilage-like nanoscale morphology that display an unusual combination of mechanical and ion transport properties. Ion-conducting membranes from these aramid nanofiber composites enable pliable zinc-air batteries with cyclic performance exceeding 100 hours that can also serve as protective covers in various robots including soft and flexible miniaturized robots. The unique properties of the aramid ion conductors are attributed to the percolating network architecture of nanofibers with high connectivity and strong nanoscale filaments designed using a graph theory of composite architecture when the continuous aramid filaments are denoted as edges and intersections are denoted as nodes. The total capacity of these body-integrated structural batteries is 72 times greater compared with a stand-alone Li-ion battery with the same volume. These materials and their graph theory description enable a new generation of robotic devices, body prosthetics, and flexible and soft robotics with nature-inspired distributed energy storage.

具有保形形状和多种功能的电池可以为机器人设备的设计提供新的自由度。例如，既提供承载又提供能量存储的能力可以增加有效负载并扩展机器人的操作范围。然而，实现这些类型的结构动力装置需要开发具有合适的机械和离子传输特性的材料。在这里，我们报道了仿生的基于芳族聚酰胺纳米纤维的复合材料，具有类似软骨的纳米级形态，显示出机械和离子传输特性的异常组合。由这些芳族聚酰胺纳米纤维复合材料制成的离子导电膜可以使柔韧性的锌-空气电池具有超过100小时的循环性能，还可以用作各种机器人的保护罩，包括软性和柔性小型化机器人。芳族聚酰胺离子导体的独特性能归因于具有高连通性的纳米纤维的渗流网络体系结构和坚固的纳米级细丝，当连续的芳族聚酰胺细丝表示为边缘并且交叉点表示为节点时，使用复合结构的图论设计。与体积相同的独立锂离子电池相比，这些车身集成式结构电池的总容量大72倍。这些材料及其图形理论的描述使新一代机器人设备，人体修复以及具有自然灵感的分布式能量存储的柔性软机器人成为可能。