材料汇·2025-08-14 13:21Core Viewpoint - The article discusses the advancements and challenges of anode-free battery technology, highlighting its potential for higher energy density and lower costs compared to traditional lithium-ion batteries. It also addresses the technical issues such as lithium dendrite growth and SEI film instability, along with solutions being explored by companies like CATL and BYD [2][5][9]. Group 1: Advantages of Anode-Free Technology - Anode-free batteries offer higher energy density due to higher discharge voltage and reduced weight and volume, achieving a mass energy density of 650 Wh/kg and a volume energy density of 1300 Wh/L [5][6]. - The technology simplifies the manufacturing process by reducing the need for metallic lithium, thereby lowering overall battery costs [6]. Group 2: Key Challenges - Lithium dendrite formation poses a significant risk, as lithium ions directly deposit on the current collector, leading to uneven growth and potential short circuits [9]. - The instability of the SEI film, which can break and reform during lithium deposition and stripping, consumes active lithium ions and reduces battery capacity [10]. Group 3: Solutions to Challenges - Solutions focus on four main areas: current collector modification, SEI film stabilization, lithium supplementation, and electrolyte optimization [16]. - Modifying current collectors involves creating a three-dimensional structure to enhance surface area and lithium affinity, which helps suppress dendrite growth [17][18]. - Optimizing electrolytes includes using high-concentration solutions to minimize side reactions and potentially employing solid-state electrolytes [16]. Group 4: Industry Progress - CATL announced its "self-generating anode" technology, which improves energy density by 60% in volume and 50% in mass, while enhancing ion conductivity by 100 times and reducing active lithium consumption by 90% [25]. - BYD has patented a porous sponge-like current collector that gradually increases lithium affinity, achieving a porosity of 40-60 wt%, which helps accommodate lithium ions and reduce dendrite formation [30].