In the last decade, we witness an active search for an efficient, reliable and long-lasting power source for miniature devices and wireless sensors. One of the promising energy conversion methods for the development of such a power source is the direct-charge energy-harvesting method. This technique is implemented in a vacuum capacitor arrangement. In this setting, the kinetic energy of the emitted particles is converted into usable electrical energy without intermediate steps. In this work, we introduce a systematic analysis of the performance of this method in terms of appropriate transfer functions describing the main energy loss mechanisms that govern its efficiency. The individual contributions of these mechanisms are determined and integrated in order to evaluate the overall efficiency. To demonstrate the validity of our analysis, it is applied to a specific harvester for which experimental measurements are available. The predicted efficiency and volumetric power density are compared with the experimental findings under various operational configurations. Excellent agreement of our predicated performances with the experimental results is revealed. The analysis enables to predict the performance envelope of the harvester. Thus, it can be used for the design and optimization of direct charge $\beta $ -radiation devices. In the specific device examined, the predicted highest efficiency is 13.5%.

中文翻译：

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直接充电β射线辐射能量收集方法的性能分析

在过去的十年中，我们目睹了针对微型设备和无线传感器的高效，可靠且持久的电源的积极探索。用于开发这种电源的有希望的能量转换方法之一是直接充电能量收集方法。该技术在真空电容器装置中实现。在这种情况下，发射的粒子的动能无需中间步骤即可转换为可用的电能。在这项工作中，我们将通过描述适当的传递函数（描述控制其效率的主要能量损失机制）的方法，对该方法的性能进行系统的分析。确定并整合这些机制的个人贡献，以评估总体效率。为了证明我们分析的有效性，它适用于可以进行实验测量的特定收割机。将预测的效率和体积功率密度与各种操作配置下的实验结果进行比较。揭示了我们的预测性能与实验结果的极好的一致性。该分析能够预测收割机的性能范围。因此，它可以用于直接充电的设计和优化 $ \ beta $ -辐射装置。在检查的特定设备中，预测的最高效率为13.5％。