A solid-state lithium battery is a battery that uses a solid-state motor and a solid-state electrolyte. Compared with traditional liquid lithium-ion batteries, solid-state batteries have higher energy density, faster charging speed, higher safety and longer life. The working principle of solid-state batteries is similar to that of traditional lithium-ion batteries, which are based on the migration and charge transfer of lithium ions between the positive and negative electrodes. When the battery is charged, lithium ions migrate from the positive material to the negative material, and electrons flow from the negative to the positive electrode. When the battery is discharged, lithium ions migrate from the negative material to the positive material, while electrons flow from the positive to the negative.
Advantages of solid-state batteries:
1. Light and high energy density. The energy density can reach twice that of ternary lithium batteries, and in the case of the same capacity, it can be smaller and lighter.
2. Higher security. If the liquid electrolyte leaks or is destroyed, it can cause thermal runaway, explosion or deflagration. The solid electrolyte is non-flammable, and even if the diaphragm is pierced, it will not leak and volatilize, and the safety can be greatly improved.
3. Long cycle life. Affecting the cycle life of lithium-ion batteries is that the number of lithium ions is decreasing, and when lithium ions migrate to the negative surface, some lithium ions do not enter the negative active substance to form a stable compound, obtain electrons and deposit on the negative surface to become lithium metal, and no longer participate in the subsequent cycle process, resulting in a decrease in capacity. The solid electrolyte solves the problem of the solid electrolyte interface film formed by the liquid electrolyte during the charging and discharging process, and greatly improves the cycle life of the lithium battery.
Disadvantages of solid-state batteries:
1. High production cost. Because solid-state batteries use complex processes such as high temperature and high pressure in the production process, the production cost of solid-state batteries is generally higher at this stage.
2. Slow conduction speed. Solid electrolytes have lower conductivity than liquids and are difficult to charge at high rates.
The research and development and production of solid-state batteries have further deepened the foundation of the application of lithium batteries in traditional industries, and also extended the possibility of future applications of lithium batteries in aviation, robotics and so on. It is believed that solid-state batteries will further reduce costs and improve the cost performance of applications in the future.