SIMT Technology Observation Nayuan new materials
SIMT Technology Observation is a cutting-edge technology and industry transformation in-depth dialogue column launched by Sodium Yuan New Materials (SIMT). As an important component of the Na Yuan new material technology ecosystem, this column will regularly invite experts from fields such as new energy, artificial intelligence, materials science, and intelligent manufacturing Frontline PhDs and Researchers In the form of dialogue, break down the technical challenges they have overcome, the latest developments in the laboratory, and the real path from theory to industrialization.
👤 Interview guests for this issue
Professor Jun Wang obtained his doctorate degree in material physics and chemical engineering from Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences in 2012, served as a researcher in MEET Battery Research Center (European Top Battery Research Center), University of Munster, Germany from 2012 to 2018, and has served as a researcher/professor and doctoral supervisor in South University of Science and Technology since 2018. Its main research direction isResearch on high-energy density and high safety lithium batteries, as well as other new types of batteriesHosted sub projects of the National Natural Science Foundation of China, Guangdong Provincial Key R&D Program, and Shenzhen Major Technology Research Project, served as a young editorial board member of eScience, Sci. China Mater., Energy Storage Science and Technology Journal, and vice chairman of the New Materials Professional Technical Committee of Guangdong Provincial Youth Science and Technology Innovation Research Association.already in Nat. Rev. Chem., Chem. Soc. Rev., Nat. Commun., Joule，Energy Environ. Sci.，Adv. Mater.，Angew. Chem. Published over 200 academic papers in top international journals, with more than 9500 citations and an H-index of 53; Applied for over 50 invention patents.
If we only look at the capital market and public opinion field, solid-state batteries seem to be a technology that is about to emerge: they are safer, have higher energy density, and can also be compatible with lithium metal negative electrodes. It seems that only the last step is needed to replace today's liquid lithium-ion batteries and become the standard answer for the next generation of power batteries.
In the past two years, judgments such as mass production in 2027 and large-scale application in 2030 have frequently appeared, coupled with the continuous increase of car companies, material companies, and battery companies. Solid state batteries have almost become one of the most concerned technological directions in the entire new energy industry.
But if we pull the perspective back from the capital narrative to the laboratory, material system, and battery manufacturing site, we will find a judgment that is closer to reality:The technology of solid-state batteries has been successfully implementedHowever, there is still a long way to go before the comprehensive industrialization of large capacity, long lifespan, mass production, and delivery can be achieved.
To understand solid-state batteries, the first step is to answer a more fundamental question:What is the liquid electrolyte doing in today's lithium-ion batteries?
Only by understanding why liquid electrolytes have long dominated can we understand why solidification is a much more complex system reconstruction than imagined.
01 Electrolyte, in battery systems; Blood ";
Professor Wang:;The electrolyte is actually the blood of the battery.The thermal runaway of batteries often begins with the decomposition of the electrolyte. The reason why we choose to use semi-solid and all solid electrolytes is because liquid electrolytes are prone to leakage, combustion, and explosion. If we compare a battery to a house, the positive pole determines the ceiling, the negative pole determines the floor, and the electrolyte determines whether it can fit in. "
1. There is enough widthElectrochemical stability windowOtherwise, it will preferentially oxidize and decompose in front of the high-voltage positive electrode;
2. Yes, there isAppropriate viscosity and good wettabilityOnly then can it truly penetrate into the interior of the porous electrode and establish a continuous ion transport network;
3、Ionic conductivity should be high enoughTo ensure magnification performance and transmission efficiency under low temperature conditions;
4. Must be formed on the positive and negative electrode surfacesStable, uniform and sustainable facial maskTo prevent the battery from continuously experiencing side reactions, impedance rise, gas evolution, and structural instability during cycling.
5、还不能忽略产业层面的限制，必须建立在可量产、可储运、成本可控、环境与法规可接受的基础上。
这意味着，液态电解液之所以能够支撑今天锂离子电池的大规模产业化，不只是因为它“能导电”，更因为它在传输、浸润、界面和制造适配性之间，提供了一种经过多年优化的综合平衡。
正因如此，固态电池要替代液态体系，讨论的实际是如何替代掉液态电解液在整个系统中承担的这些复合功能。
02 固态电池难点，界面工程问题
决定系统表现的，不只是某个材料本体的指标，而是它们之间如何接触、如何反应、如何在长期循环中保持兼容。
Wang教授："液态电解液是液相传导，从溶剂化到脱溶剂化；固态电解质是缺陷传导和晶界传导。这两种传导方式的迁移速率、活化能和路径长度都是不一样的。"
⚡ 固态电池界面难题 · 四维解析 | |
| 固-固接触 | |
| 化学兼容性 | |
| 力学稳定性 | |
| 尺度放大 | |
03 界面之外，结构工程与制造体系的重建
Wang教授："固态电池的正极并没有使用新的材料，但是它的工程结构是不一样的。"
因此，固态电池的正极不再只是活性材料加导电剂和粘结剂的简单组合，而要引入固态电解质颗粒，并重新设计颗粒分布、空隙率、致密化程度、成型压力和层间接触关系。
这也意味着，固态电池的迭代升级，不只是给现有液态产线换一种电解质，而是要重构电极加工逻辑、层压方式、压力管理方式乃至封装思路。
04 产业现实，固态电池何时能普及
"2027 年量产可以实现小规模一定应用，但会有一定的应用场景受限，可能是率先在高端车、低空领域落地。虽然影响固态电池量产应用的不确定因素很多，但可以确认的是， 2027 年到 2030 年是一个比较关键的时间节点。 "
从产业规律看，任何新型电池技术真正走向主流，至少要同时满足几项条件：
● 关键材料与界面问题得到足够稳定的解决；
对于固态电池而言，这几项条件目前还都处在逐步打通的过程中，因此未来几年固态电池大概率“不会全面替代液态电池”，而会应用在那些对量密度或品牌技术形象更敏感、同时能承受更高成本的高端车型和特种场景中。
换言之，目前固态电池更可能经历的是“从示范应用到逐步放量”的过程，距离全面普及走进千家万户，还有一段路需要走。
05 再看钠电，不同维度的创新发展
⚖️ 钠离子电池 · 优势与挑战 |
| ✅ 核心优势资源丰富、成本友好钠的地壳储量远高于锂，分布均匀，不受地缘政治制约，具备大规模普及的资源基础。正极材料选择更灵活更容易采用铁、锰、铜等相对廉价的过渡金属元素体系，从而降低对镍、钴、锂等稀缺资源的依赖，供应链安全性显著提升。 |
| ⚠️ 结构挑战离子半径导致结构不稳定钠离子半径明显大于锂离子，在嵌入和脱出正极结构时更容易引发层间滑移、结构畸变和复杂相变，在锂电体系中还能维持稳定的结构，到了钠电中往往会表现出更强烈的不稳定性。 |
Wang教授："聚阴离子的容量比较好，结构非常稳定，循环性非常好，安全性也比较好。“
Wang教授："层状氧化物的能量密度已经能够做到接近160Wh/kg，与市面上磷酸铁锂180Wh/kg比较接近。随着新材料开发，很有希望突破甚至大于磷酸铁锂。"
