Advanced Membrane-Free Electrochemical Energy Storage Devices (Phase 1)

先进无膜电化学储能器件（一期）

• 批准号: 566840-2021
• 负责人: Thangadurai, Venkataraman
• 金额: $ 9.11万
• 依托单位: University of Calgary
• 依托单位国家: 加拿大
• 项目类别: Idea to Innovation
• 财政年份: 2021
• 资助国家: 加拿大
• 起止时间: 2021-01-01 至 2022-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=728652
• 关键词: Advanced; Membrane; Free; Electrochemical; Energy

Energy storage is required for making renewable electricity generation, such as wind and solar, dispatchable. A variety of energy storage technologies are technically mature and commercially available. Among these, redox flow batteries (RFBs) operating with vanadium electrochemistry (vanadium redox flow battery, VRFB) offer a unique advantage of independently sizing power and energy density, and are therefore a promising candidate for grid and off-grid stationary energy storage applications. However, the current generation of RFBs suffer from operational inefficiency, primarily due the use of Nafion membrane that separates the anolyte and catholyte. Yet it is necessary to allow the movement of protons across the membrane to support the fundamentals of electrochemistry. The membrane is incapable of preventing vanadium ion crossover through it resulting in electrolyte dilution and efficiency loss, and limiting the battery operating temperature range, generally above 40°C. Additionally, the Nafion membrane is costly and approximately represents 40% of the cell stack cost. We are proposing a radically innovative RFB/VRFB design in which the membrane as well as the associated technical issues are eliminated. In our design, the membrane is replaced with auxiliary electrodes (AE's) made of metal oxides (SnO/SnO2), that change their oxidation states (Sn2+/Sn4+) during charging/discharging, balance the charges in the anolyte and catholyte, and provide the necessary electrochemistry for the electrochemical energy storage. AEs eliminate ionic movement between electrolyte compartments and completely prevent electrolyte crossover without negatively impacting cell performance. This novel design also provides an opportunity to use high-energy-dense electrolytes in the RFB system with flexible operating conditions. Five HQPs will be trained in the RFB technology during this project. These HQPs will be skilled in technical and business aspects of energy storage and suitable for high-demand energy storage positions in industry and academia in the near future.

为了使风能和太阳能等可再生能源发电可调度，需要储能。各种储能技术在技术上已经成熟，并可在商业上获得。其中，利用钒电化学工作的氧化还原液流电池（RFB）（钒氧化还原液流电池，VRFB）具有独立调整功率和能量密度的独特优势，因此是电网和离网固定能源存储应用的有前途的候选者。然而，当前一代的RFB遭受操作效率低的问题，这主要是由于使用了分隔阳极电解液和阴极电解液的Nafion膜。然而，为了支持电化学的基本原理，允许质子穿过膜的运动是必要的。该膜不能防止钒离子穿过它，导致电解质稀释和效率损失，并限制电池工作温度范围，通常高于40°C。此外，Nafion膜是昂贵的，约占电池堆成本的40%。我们提出了一种彻底创新的RFB/VRFB设计，其中消除了膜以及相关的技术问题。在我们的设计中，用由金属氧化物（SnO/SnO 2）制成的辅助电极（AE）代替膜，所述辅助电极在充电/放电期间改变它们的氧化态（Sn 2 +/Sn 4+），平衡阳极电解液和阴极电解液中的电荷，并为电化学能量存储提供必要的电化学。AE消除了电解质隔室之间的离子运动，并完全防止电解质交叉，而不会对电池性能产生负面影响。这种新颖的设计还提供了在具有灵活操作条件的RFB系统中使用高能量密度电解质的机会。在本项目期间，将对五名HQP进行RFB技术培训。这些HQP将熟练掌握储能的技术和业务方面，并适合在不久的将来在工业和学术界的高需求储能职位。