Waste management is one of the biggest environmental challenges worldwide. Biomass-derived hard carbons, which can be applied to rechargeable batteries, can contribute to mitigating environmental changes by enabling the use of renewable energy. This study has carried out a comparative environmental assessment of sustainable hard carbons, produced from System A (hydrothermal carbonization (HTC) followed by pyrolysis) and System B (direct pyrolysis) with different carbon yields, as anodes in sodium-ion batteries (SIBs). We have also analysed different scenarios to save energy in our processes and compared the biomass-derived hard carbons with commercial graphite used in lithium-ion batteries. The life cycle assessment results show that the two systems display significant savings in terms of their global warming potential impact (A1: −30%; B1: −21%), followed by human toxicity potential, photochemical oxidants creation potential, acidification potential and eutrophication potential (both over −90%). Possessing the best electrochemical performance for SIBs among our prepared hard carbons, the HTC-based method is more stable in both environmental and electrochemical aspects than the direct pyrolysis method. Such results help a comprehensive understanding of sustainable hard carbons used in SIBs and show an environmental potential to the practical technologies.

This article is part of the theme issue ‘Bio-derived and bioinspired sustainable advanced materials for emerging technologies (part 2)’.

废物管理是全球最大的环境挑战之一。生物质衍生的硬碳可应用于可充电电池，可通过使用可再生能源来缓解环境变化。本研究对由系统 A（水热碳化（HTC）随后热解）和系统 B（直接热解）生产的具有不同碳产量的可持续硬碳进行了比较环境评估，作为钠离子电池 (SIB) 的阳极. 我们还分析了在我们的过程中节省能源的不同场景，并将生物质衍生的硬碳与锂离子电池中使用的商业石墨进行了比较。生命周期评估结果表明，这两个系统在全球变暖潜在影响方面显示出显着的节约（A1：-30%；B1：-21%），其次是人体毒性潜能、光化学氧化剂产生潜能、酸化潜能和富营养化潜能（均超过-90%）。在我们制备的硬碳中，基于 HTC 的方法对 SIBs 具有最佳的电化学性能，在环境和电化学方面都比直接热解方法更稳定。这些结果有助于全面了解 SIB 中使用的可持续硬碳，并展示实用技术的环境潜力。基于 HTC 的方法在环境和电化学方面都比直接热解方法更稳定。这些结果有助于全面了解 SIB 中使用的可持续硬碳，并展示实用技术的环境潜力。基于 HTC 的方法在环境和电化学方面都比直接热解方法更稳定。这些结果有助于全面了解 SIB 中使用的可持续硬碳，并展示实用技术的环境潜力。

本文是主题问题“用于新兴技术的生物衍生和仿生可持续先进材料（第 2 部分）”的一部分。