国泰海通｜新能源：固态电池正负极&集流体发展方向

Core Viewpoint - Solid-state batteries are considered the next generation of lithium batteries due to their high energy density and safety compared to liquid batteries [1][2]. Group 1: Positive Electrode Development - The positive electrode is evolving towards high voltage and high specific capacity, with initial reliance on high nickel ternary materials, transitioning to lithium-rich manganese-based and ultra-high nickel materials in the future [1]. - Lithium-rich manganese-based (LMR) materials have a theoretical specific capacity of 320mAh/g and a voltage platform of 3.7V-4.6V, significantly outperforming traditional ternary and lithium iron phosphate materials [1]. - The raw material cost for lithium-rich manganese-based materials is approximately 15-20% lower than that of ternary materials, with energy cost per watt-hour close to that of lithium iron phosphate [1]. Group 2: Negative Electrode Development - Short-term focus for negative electrodes is on silicon-carbon composites, while lithium metal is expected to become the mainstream material post achieving an energy density of 400Wh/kg [2]. - The theoretical specific capacity of lithium metal (3860mAh/g) is vastly superior to that of traditional graphite electrodes (372mAh/g), contributing to enhanced energy density [2]. - Current mainstream preparation methods for lithium metal electrodes include rolling, with future advancements in vapor deposition techniques expected to facilitate their implementation [2]. Group 3: Current Collector Innovations - Future developments in solid-state batteries may center around lithium metal electrodes and sulfide electrolytes, with porous copper foils being utilized to suppress lithium dendrite growth, thereby enhancing safety and cycle life [2]. - Nickel-based and stainless steel current collectors are proposed as suitable alternatives to address the corrosion issues associated with sulfide electrolytes [2].