Development/characterization of materials for electrochemical energy storage

公众对温室气体排放导致的全球气候变化的认识，促使风能和太阳能等可再生能源的利用不断增加，而且还将进一步增加。这些能源本质上是间歇性的，因此需要有效的方法来储存电力以供以后使用。高效的电化学储能（EES）装置是采用这些替代能源的关键部件。EES设备是用来存储化学能的介质，这些化学能稍后可以转换回电能。电池存储是提供存储的一种方式，尽管也可以通过电解水以氢的形式存储能量。EES设备的开发和商业化受到许多材料工程问题的限制，这些问题与这些设备的制造、操作和长期可靠性有关。拟议的研究计划将集中于开发和表征用于EES应用的新材料，重点是两种类型的设备，锌离子电池（ZIBs）和固体氧化物电解电池（soec）。固体氧化物燃料电池（sofc）是一种将化学能转化为电能的装置。典型的燃料是氢（尽管可以使用其他燃料），它在阳极氧化成水，释放电子。SOEC本质上是一个反向操作的SOFC。两者可以结合在一个单一的设备，称为固体氧化物电池（SOC）。通常，氢电极是由钇稳定的氧化锆（YSZ）和镍（Ni）组成的金属陶瓷。限制商业应用的问题之一是该电极的长期稳定性。降解机制尚不清楚，但一般认为与Ni有关，即Ni迁移，Ni团聚和Ni在气相中的损失。研究退化机制并提出/实施可能的解决方案是该部分研究项目的重点。锌锌板是储存大量电能的有希望的候选材料，因为锌广泛可用且价格低廉。ZIBs使用高容量锌（Zn）金属阳极、金属氧化物阴极和水性电解质，其能量/功率密度与锂离子电池（lib）相似。与lib相比，zib具有许多优势，包括安全性、环保性和制造条件更简单。然而，有一些缺点限制了可充电zib的实际应用。这些问题包括效率低下、副产品的形成以及由于电池循环过程中与金属氧化物阴极相关的不可逆反应而导致的容量快速衰退。提高效率和稳定性的关键是合理设计稳定、高容量的新型锌离子电极材料。这项工作的重点是开发改进的锌插入阴极，以实现多次循环的高能量密度。

Public awareness of global climate change resulting from greenhouse gas emission has led to increasing utilization of renewable energy sources such as wind and solar, with further increases on the horizon. These sources are inherently intermittent in nature, necessitating effective methods of storing power for later use. High efficiency electrochemical energy storage (EES) devices are a key component to adopting these alternative energy sources. EES devices are the media used to store chemical energy that can be later converted back to electricity. Battery storage represents one way of providing storage, although energy could also be stored in the form of hydrogen through the electrolysis of water. EES device development and commercialization are limited by a number of materials engineering issues related to the fabrication, operation and long term reliability of these devices. The proposed research program will concentrate on the development and characterization of novel materials for EES applications, with an emphasis on two types of devices, zinc-ion batteries (ZIBs) and solid oxide electrolysis cells (SOECs). Solid oxide fuel cells (SOFCs) are devices that convert chemical energy into electrical energy. The typical fuel is hydrogen (although other fuels can be utilized) which is oxidized to water at the anode with electrons being released. An SOEC is essentially an SOFC operating in reverse. The two can be combined in a single device, referred to as a solid oxide cell (SOC). Typically, the hydrogen electrode is a cermet consisting of yttria stabilized zirconia (YSZ) and nickel (Ni). One of the issues limiting commercial application is long term stability of this electrode. The degradation mechanisms are not well understood, but are generally believed to be associated with Ni, i.e., Ni migration, Ni agglomeration and loss of Ni in the vapour phase. Studying the degradation mechanisms and proposing/implementing possible solutions is the focus of this part of the research project.ZIBs are a promising candidate to store large amounts of electricity, since zinc is widely available and inexpensive. ZIBs use a high-capacity zinc (Zn) metal anode, metal oxide cathodes and aqueous electrolytes, with energy/power densities similar to lithium-ion batteries (LIBs). ZIBs offer advantages over LIBs, including improved safety, eco-friendliness and simpler manufacturing conditions. There are, however, drawbacks that restrict practical application of rechargeable ZIBs. These include poor efficiency, the formation of byproducts and rapid capacity fading due to the irreversible reactions associated with the metal oxide cathodes during battery cycling. The key to increasing efficiency and stability is to properly design new stable and high-capacity Zn-ion electrode materials. This work focuses on developing improved Zn-insertion cathodes to enable high energy densities over many cycles.