Do you know what a solid-state lithium-ion battery is? With the rapid development of society, our solid-state lithium-ion batteries are also developing rapidly. Do you know the detailed information about solid-state lithium-ion batteries? Let me guide you through a detailed understanding of the relevant knowledge.
A "solid-state lithium battery" is a type of lithium battery in which both the electrode and electrolyte materials are solid within the operating temperature range, containing no liquid components. Its full name is "solid-state electrolyte lithium battery." Therefore, "solid-state lithium battery" is the most abbreviated name, and it cannot be shortened. To aid understanding, Professor Ouyang used the analogy of "all-solid-state" being different from "solid-state," and "lithium battery" being a different concept from "lithium-ion battery." Solid-state lithium batteries are further divided into primary solid-state lithium batteries and secondary solid-state lithium batteries. Primary batteries are already in use. Secondary solid-state lithium batteries are further divided into lithium-ion batteries and lithium metal batteries, which are two concepts that need to be distinguished.
Solid-state lithium-ion batteries are those where both the electrodes and electrolyte are in a solid state. Currently, most commercially available lithium-ion batteries use liquid or polymer electrolyte materials.
Solid lithium thin-film secondary batteries are fabricated on a substrate in the order of anode, electrolyte, and cathode, and then encapsulated into a battery. During the fabrication process, appropriate techniques are used to prepare each thin-film layer of the battery. Generally, the negative electrode is made of metallic lithium and prepared using vacuum thermal deposition (VD) technology. The electrolyte and positive electrode, including oxide negative electrodes, can be prepared using various sputtering techniques, such as radio frequency sputtering (RFS) and radio frequency magnetron sputtering (RFMS).
Liquids readily combine with solids, penetrating each other. However, solid-to-solid contact and stability are less than ideal, a significant problem. While sulfide electrolytes have improved lithium-ion conductivity, they still suffer from interfacial contact and stability issues. A third problem is the rechargeability of metallic lithium. In solid-state electrolytes, lithium surface pulverization and dendrite growth also exist. Their cycle life and even safety require further investigation. Furthermore, high manufacturing costs are a major obstacle to their development.
Of course, solid-state batteries also face some development challenges, the biggest of which is the significant difference in conductivity compared to liquid electrolytes. Furthermore, the interfacial stability between the solid electrolyte and electrode materials is another issue that needs to be addressed.
In terms of manufacturing processes, due to the poor elasticity of current solid electrolyte membranes, solid-state battery assembly tends to be more layered than winding processes, but the specific sub-processes are unknown. Regarding manufacturing equipment, although solid-state batteries differ significantly from traditional lithium-ion batteries, there is no fundamental difference beyond the need for customized equipment in coating and packaging processes, and the requirement for a more demanding drying environment.
Solid electrolytes are mainly classified into two types: inorganic electrolytes and polymer electrolyte materials. Some parameters for evaluating solid electrolytes include: high ionic conductivity, low ionic resistivity, high electronic resistivity, high ion selectivity, wide electrochemical stability window, good chemical compatibility, excellent thermal stability, excellent mechanical properties, simple preparation process, low cost, easy integration, and environmental friendliness.
The above is a detailed analysis of the relevant knowledge about solid-state lithium-ion batteries. We need to continuously accumulate experience in practice so that we can design better products and contribute to the better development of our society.
