Are solid-state batteries absolutely more environmentally friendly compared to traditional batteries-analyzing from the footprint family viewpoint

In recent years, with the change of global climate, carbon neutralization has become a global consensus. Solid state batteries have become the important way to develop batteries in the future due to their advantages such as high safety, high energy density, wider operating temperature range, and the battery production stage is the main contributor to the environmental impact of the battery life cycle.This article selects three traditional batteries, LFP battery, NMC battery, LTO battery, and two new solid-state batteries, Li-FeS₂ battery and LLZO battery, to conduct a study on the carbon footprint and other footprint family impacts during the production stage. The inventory data is collected from highly cited literature published in recent years, and the footprint family impact values generated by different types of battery packs are compared and analyzed. When using 1 kg as the functional unit, the footprint values of LLZO and Li-FeS₂ solid-state batteries are higher than those of NMC and LFP traditional batteries in most footprint indicators such as ionizing radiation and ozone layer depletion in carbon footprint, material footprint, ecological footprint, and health footprint, resulting in greater environmental pollution. Considering the energy density of the battery, with a functional unit of 1kWh, the high energy density of solid-state batteries significantly reduces their environmental impact, while traditional battery LTO increases its environmental impact due to the lower battery energy density. But in the material footprint, both functional units of solid-state batteries have a significant impact. The high energy density of solid-state batteries still holds great development prospects, and cleaner technology and energy, as well as higher energy density, remain the direction of battery development.