Tracing the technology development and trends of hard carbon anode materials - A market and patent analysis

As the demand for energy storage is expanding rapidly, concerns have been raised about critical raw materials used in lithium-ion batteries. Post-lithium batteries have the potential to provide a more sustainable option for energy storage by taking advantage of raw materials that are more abundant and unrestricted by supply chains. Sodium-ion batteries are one type that is currently the most widely discussed candidate in light of the approaching commercialization. The most promising anode material for commercial sodium-ion batteries that can be applied in large quantities in the near future is expected to be hard carbon (HC). However, neither the current state of HC's commercialization nor the trend in technology development has been investigated. This work uses an approach that combines literature investigation, expert surveys, and patent analysis to track the growth route of HC and identify potential obstacles. The analysis of 352 HC-related patents and existing production operations shows that the HC market is still in the early phase of market development. As of now, production capacities are limited due to a lack of market forces and uncertain demand. Uneven distribution of market and research activities, lack of information transparency of the upstream supply chain, and potential hype stemming from market immaturity are highlighted as potential challenges in the HC market. To accelerate the commercialization of HC, as a prerequisite for a successful introduction of sodium-ion batteries to the future market, more investment and efficient market conversion of R&D efforts are required. This article offers recommendations to promote the sustainable design and marketing plans of HC-based battery systems.