Electric vehicle batteries are intricate and comprise numerous components, including battery cells, modules, wiring, a battery management system (BMS), a thermal management system, separators, and an electrolyte, all enclosed within a protective housing. This battery pack can account for 30 to 50 percent of the vehicle’s value and approximately 40 percent of its weight. With raw materials constituting a significant portion of the battery’s value, recycling the battery pack can reclaim almost a third of the car’s value, which is not achievable with other vehicle components.
The automotive industry currently relies completely on lithium-ion (Li-ion) batteries for the majority of plug-in vehicles due to their exceptional properties, as highlighted by the Atlantic Council, which states, “The Li-ion battery’s namesake mineral is incredibly difficult to substitute, thanks to its high conductivity and lightweight nature.” These batteries consist of various components, with the cathode being a crucial element responsible for collecting electrons during the electrochemical process. Li-ion battery cells come in three types: cylindrical, prismatic, and pouch.
Composition of Electric Vehicle Batteries
Battery cells in electric vehicles come in diverse chemistries, shapes, and sizes, tailored to suit pack manufacturers’ preferences. These packs invariably comprise multiple cells interconnected in series and parallel configurations to meet the overall voltage and current requirements. Electric drive EVs often feature battery packs housing numerous individual cells, each with a nominal voltage of 3-4 volts, depending on their chemical composition. The five main battery materials are lithium, nickel, cobalt, manganese, and graphite.
The cell contains a cathode Active material onto which lithiation is a composite that include elements like cobalt, manganese, and iron, depending on the chosen chemistry. This cathode chemistry significantly impacts the performance of the cell and, consequently, the battery itself. It also plays a vital role in end-of-life (EOL) handling, affecting the return on investment (ROI) of the recycling process. Furthermore, the recycling process determines which materials can be effectively recovered.
On the other hand, the anode, predominantly using graphite in Li-ion batteries, transports electrons through the electrolyte to the cathode. Electric vehicle (EV) batteries typically range from 30kWh to 100kWh, requiring approximately 1 kg of graphite per kWh of battery energy.
Breaking down the cost of a lithium-ion cell, reveals that the cathode cost encompasses mining and refining expenses. BloombergNEF emphasizes that even after excluding processing costs, the raw materials in the cathode still account for approximately one-third of the total cell cost.
Estimating Battery Weight
Battery weights vary across the automotive industry, depending on vehicle size and application. On average, a battery weighs approximately 6 kg per kWh. Different EV models have different battery capacities, making it difficult to assign an exact average weight.
The Heart of the Battery: The Cell
Battery cells are the core of electric vehicle batteries and are organized into modules. Each cell contains a cathode (positive pole), electrolyte, separators, and an anode (negative pole). Lithium-ion battery technology dominates the EV market, and common materials in Li-ion batteries include lithium and graphite, along with other materials like Cobalt, Nickel, Manganese in different ratios depending on the cathode chemistry.
In a nutshell, the battery industry is at the forefront of the transition to a more sustainable energy future. Recycling and sustainable design of battery components, such as enclosures and cells, are crucial for reducing environmental impact and ensuring the longevity of EVs and other battery-intensive applications. As global demand for batteries continues to rise, addressing these challenges becomes increasingly important.
