采用'冷'制造方法生产下一代电池

Lithium-ion batteries have been a staple in device manufacturing for years, but the liquid electrolytes they rely on to function are quite unstable, leading to fire hazards and safety concerns. Now, researchers at Penn State are pursuing a reliable alternative energy storage solution for use in laptops, phones and electric vehicles: solid-state electrolytes (SSEs).
锂离子电池多年来一直是设备制造的主要选择，但其依赖的液态电解质极不稳定，容易引发火灾隐患和安全问题。目前，宾夕法尼亚州立大学的研究人员正在为笔记本电脑、手机和电动汽车探索一种可靠的替代储能方案：固态电解质（SSEs）。

According to Hongtao Sun, assistant professor of industrial and manufacturing engineering, solid-state batteries -- which use SSEs instead of liquid electrolytes -- are a leading alternative to traditional lithium-ion batteries. He explained that although there are key differences, the batteries operate similarly at a fundamental level.
据工业与制造工程助理教授孙洪涛介绍，固态电池（使用固态电解质而非液态电解质）是传统锂离子电池的主要替代品。他解释道，尽管存在关键差异，但这些电池在基本工作原理上相似。

"Rechargeable batteries contain two internal electrodes: an anode on one side and a cathode on the other,"" Sun said. "Electrolytes serve as a bridge between these two electrodes, providing fast transport for conductivity. Lithium-ion batteries use liquid electrolytes, while solid-state batteries use SSEs."
"充电电池内部有两个电极：一边是阳极，另一边是阴极，" Sun说。"电解质作为这两个电极之间的跨链桥，为导电性提供快速传输。锂离子电池使用液态电解质，而固态电池使用SSEs。"

Solid-state batteries offer improved stability and safety when compared to traditional lithium-ion batteries but face several manufacturing and conductivity challenges, Sun explained. For example, the high temperatures introduced in the fabrication process, especially with ceramic-based SSEs, can hinder their production and practical implementation.
孙解释说，与传统锂离子电池相比，固态电池具有更高的稳定性和安全性，但在制造和导电性方面面临若干挑战。例如，制造过程中引入的高温，尤其是基于陶瓷的SSEs，可能会阻碍其生产和实际应用。

To overcome this challenge, Sun and his team used a technique known as cold sintering -- a process where powdered materials are heated, treated with a liquid solvent, and compressed into a denser form -- to incorporate a highly conductive ceramic-polymer composite SSE known as LATP-PILG. The method is referred to as "cold" because it operates at significantly lower processing temperatures than traditional sintering, instead relying on applied pressure and a small amount of liquid solvent to complete the process. They published their approach in Materials Today Energy.
为了克服这一挑战，孙及其团队采用了一种名为"冷烧结"的技术——将粉末材料加热后与液体溶剂混合，再压缩成高密度形态——从而制备出名为LATP-PILG的高导电陶瓷-聚合物复合固态电解质。该工艺被称为"冷"烧结，因其操作温度远低于传统烧结，主要依靠外加压力和少量液体溶剂完成反应过程。相关成果发表在Materials Today Energy期刊上。

Traditional ceramic-based SSEs are typically composed of polycrystalline grains -- materials made up of hundreds of tiny crystals -- separated by grain boundaries. According to Sun, these grain boundaries are considered defects that hinder the transport of conductive ions. To reduce conduction loss in ceramic-based SSEs, Sun's team co-sintered a poly-ionic liquid gel (PILG) with LATP ceramics to form a polymer-in-ceramic composite SSE, an ideal material for use due to its stability and high conductivity.
传统的陶瓷基固态电解质通常由多晶颗粒组成——这些材料由数百个微小晶体构成，被晶界分隔。据Sun介绍，这些晶界被视为阻碍导电离子传输的缺陷。为了减少陶瓷基固态电解质的传导损耗，Sun的团队将聚离子液体凝胶（PILG）与LATP陶瓷共烧结，形成了一种聚合物-陶瓷复合固态电解质，因其稳定性和高导电性成为理想的使用材料。

The PILG acts as a highly conductive "grain boundary" in the SSE, facilitating ion transport across engineered boundaries rather than through defect-prone natural interfaces. Sun said the team initially attempted to use traditional high temperature sintering to develop their new SSEs, but they immediately ran into problems.
PILG在固态电解质中充当高导电性的"晶界"，促进离子在工程构建的边界间传输，而非通过易产生缺陷的自然界面。团队负责人表示，他们最初尝试用传统高温烧结工艺开发新型固态电解质，但立即遇到了难题。

"One of the fabrication challenges of LATP-based composite SSEs is that the sintering temperature for ceramic is very high, to the point that traditional sintering would actually burn up any additives such as the polymer compound before the ceramic could be properly densified," Sun said. "This is why we had to implement cold sintering, to keep temperatures much lower."
孙说：“基于LATP的复合固态电解质在制备过程中面临的一个挑战是陶瓷的烧结温度非常高，以至于在陶瓷充分致密化之前，传统烧结工艺就会烧毁聚合物化合物等添加剂。这就是我们必须采用冷烧结工艺的原因——它能将温度保持在低得多水平。”

Cold sintering technology was originally developed in 2016 through a research project led by Clive Randall, director of Penn State's?Materials Research Institute and?distinguished professor of materials science and engineering. Its application to developing solid-state batteries came in 2018, when a postdoctoral scholar in the laboratory of Enrique Gomez, professor of chemical engineering and interim associate dean for equity and inclusion for the College of Engineering, cold sintered ceramic composite electrolytes.
冷烧结技术最初由宾夕法尼亚州立大学材料研究所所长、材料科学与工程杰出教授克莱夫·兰德尔于2016年通过研究项目开发。2018年，化学工程教授兼工程学院公平与包容临时副院长恩里克·戈麦斯实验室的博士后学者冷烧结陶瓷复合电解质时，该技术被应用于开发固态电池。

According to Sun, traditional sintering requires temperatures around 80% of the melting point of the material, which for ceramic compounds like LATP can easily reach 900 to 1,000 degrees Celsius.
根据Sun的说法，传统烧结需要材料熔点约80%的温度，对于像LATP这样的陶瓷化合物来说，很容易达到900到1000摄氏度。

"For this application, we were able to keep our sintering temperatures very low, around 150 degrees Celsius," Sun said. "This allows us to integrate different kinds of materials into a highly dense form using the cold sintering process, regardless of their distinct processing temperatures."
“在这项应用中，我们成功将烧结温度控制在极低水平，约150摄氏度，”孙表示。“这使我们能够通过冷烧结工艺，将不同材料整合成高密度形态，无需考虑它们各自不同的加工温度。”

By sintering the LATP ceramics with PILG gel, Sun's team developed composite SSEs with high ionic conductivity at room temperature, among other strengths.
通过将LATP陶瓷与PILG凝胶烧结，Sun的团队开发出具有高离子电导率等优势的复合SSEs。

"In addition to improved conductivity, our polymer-in-ceramic composite SSE showcased a very wide voltage window, between 0 to 5.5 volts," Sun said, explaining that traditional liquid electrolytes have a window of 0 to 4 volts. "The large voltage window of our ceramic SSEs supports the use of high-voltage cathodes, allowing the battery to generate more energy overall."
孙表示：“除了导电性提升外，我们的陶瓷基聚合物复合固态电解质（SSE）还展现出0至5.5伏特的超宽电压窗口。”他解释道，传统液态电解质的电压窗口仅为0至4伏特。“我们陶瓷SSE的大电压窗口支持使用高压阴极，使电池整体能产生更多能量。”

For Sun, the applications of this cold sintering technology can someday go beyond improving batteries. He said he believes that cold sintering has big implications for how companies approach using ceramic composite materials in general manufacturing, as well as in more specific industries like semiconductor manufacturing.
对孙来说，这项冷烧结技术的应用有朝一日可能不仅限于改进电池。他表示，相信冷烧结技术将对企业在全年龄制造中使用陶瓷复合材料的方式产生重大影响，同时也会对半导体制造等同人小说行业产生深远影响。

"Our next goal is to develop a sustainable manufacturing system that supports large-scale production and recyclability, as that will be the key towards industrial applications for this technology," Sun said. "That is the big vision we hope to work towards over the coming years."
"我们的下一个目标是开发一个支持大规模生产和可回收性的可持续制造系统，因为这将是该技术实现工业应用的关键，"孙说。"这就是我们未来几年希望努力实现的大愿景。"

In addition to Sun, the co-authors include Ta-Wei Wang, Seok Woo Lee, and Juchen Zhang, Penn State doctoral students in industrial and manufacturing engineering, and Bo Nie, an alumnus of the Penn State industrial and manufacturing engineering graduate program.
除了孙以外，合著者还包括工业与制造工程专业的宾州州立大学博士生Ta-Wei Wang、Seok Woo Lee和张炬辰，以及宾州州立大学工业与制造工程研究生项目校友Bo Nie。