How is composed the Electric Vehicle Battery?

Electric batteries are the source of power for an electric vehicle. Batteries are considered the backbone of electric mobility. Electric vehicles use a battery pack which is comprised of thousands of individual cells working together. Battey consists of two main parts:

• Cathode
• Anode

Battey consists of two main parts; cathode and anode, the cathode acts as the battery’s positive side, while the anode is the negative side. An electrolyte, a chemical solution in between, permits the flow of charge between the cathode and anode. Positively charged particles of ions move through the electrolyte from the anode to the cathode creating a continuous flow of electrons to provide electricity. A Lithium-ion (Li-ion) battery is a rechargeable battery which has a higher energy density; therefore, most of electric vehicle batteries are made of Li-ion because:

• they are lightweight
• have high energy density
• perform well in high temperatures

Battery capacity is measured by Kwh; the higher Kwh, the higher battery capacity and the higher the electric vehicle range. For example, A typical 40kWh battery pack can be enough to power an electric vehicle for 150 miles or more.

How to charge and discharge an Electric Vehicle Battery?

When electric vehicle is charging, electricity is used to make chemical changes inside its batteries “Charge”. When electric vehicle is on the road, these charges are reversed to produce electricity “Discharge”. Charge and discharge process over time affect the amount of charge the batteries can store. Most electric vehicle manufacturers have a five to either year warranty on their batteries; however, the coming technology of electric vehicle batteries is predicting that an electric vehicle battery will last from ten to twenty years before it is needed to be replaced.

How Electric Vehicle Battery works?

The battery is connected to electric motors which drive the wheels. When you press the accelerator, energy stored in the battery is gradually consumed to feed power to the motor. Electric motors also work as generators, so when you take your foot off the accelerator and hit the brakes, the electric vehicle starts to slow down by converting its motion back into electricity. This regenerative braking recovers energy and stored it in the battery again improving the electric vehicle’s range.

Current challenges for Electric Vehicle Battery 

Most of electric vehicle batteries are mainly made of Lithium, and some other light metals:

• Graphite
• Cobalt
• Manganese
• Nickel

The cathode is made of cobalt, manganese, and nickel. The anode is made of graphite. Both the cathode and anode can store Lithium. Nickel in the cathode creates high energy density. This permits EVs to travel farther on a single charge. Cobalt saves the cathodes from overheating. It also helps to extend the life of EV batteries.

The future for electric mobility looks bright, but there are some warning signals coming from their supply chain by increased prices for materials needed to manufacture batteries; Lithium increased by 150%, graphite by 15%, and nickel by 25%. Increasing demand on electric vehicles has resulted to higher prices and supply problems for manufacturers. Meanwhile, supply chain constraints and geopolitical considerations related to raw materials such as nickel and cobalt present significant obstacles. China’s dominant position in the Lithium-ion supply chain is expected to continue to face supply chain constraints such as inflated air freight costs, ongoing raw material shortage of cargo ships, clogged seaports, shutdowns due to the pandemic.

New technologies for Electric Vehicle Battery 

Accordingly, the innovation race among electric vehicle companies is on to create the next-generation battery technology. Electric vehicle companies are studying ways to change the mix of chemicals they use and devoting their own development towards cheaper, faster to charge, and less vulnerable to raw material shortages. Some research is undergoing to increases the use of manganese and Lithium, while reducing the amount of cobalt. This method can reduce costs as the elements are more available. Experiments with manganese have shown it can also improve a battery’s energy density and safety.

Solid-State Batteries

Some other research is undergoing towards the Solid-State Batteries. The main difference between lithium-ion battery and solid-state battery is that the latter does not contain a liquid electrolyte, but thin layers of solid electrolytes that carry lithium ions between the cathode and anode. This can enable the use of lithium metal anode which will have battery energy density 70% higher than the current Li-ion batteries. This technology of electric vehicle batteries is expected to go for mass production from three to five years from today. By then, electric vehicle batteries will provide more energy dense that can increase the electric vehicle range and charge faster.

New compositions for a more sustainable market

Also, some industry expectations predict that a shift will occur this year and in the coming years from nickel-manganese-cobalt compositions to Lithium phosphate compositions or LFP batteries that are less expensive, more abundant, and have longer time span compared to Nickel Manganese Cobalt (NMC) and Nickel Cobalt Aluminum (NCA). LFP batteries do not contain nickel or cobalt in the cathode whose prices have been increased dramatically. Instead, these are made of Iron and Phosphorous which are more abundant and cheaper. Another innovation besides LFP batteries is cell-to-pack (CTP) technology eliminating the need for modules to house cells in the battery pack, thereby reducing the dead weight in the pack and improving the energy density of LFP batteries.

With the high demand of Lithium for battery manufacturing, researchers across the world are working to develop Na-ion technology. Na-ion is being developed by CATL, one of the world’s largest battery manufacturers, which introduced Na-ion in 2021 and plans to form an industrial supply chain by 2023. CATL is also mitigating the energy density limitations through their new AB battery pack design which can integrate both Li-ion and Na-ion cells in one pack. Na-ion relies on abundant and cost-effective minerals compared to Li-ion batteries. The cathode is made of cost-effective elements: sodium, iron, nitrogen, and carbon. Na-ion cannot use graphite anodes, so instead uses hard carbon. In addition, less copper is required as Na-ion use aluminum anode current collectors, unlike Li-ion. This shall be useful to reduce the demand on Lithium, Graphite, and Cobalt.

Battery recycling and electrical transition

Also, battery recycling is considered one of the key targets for sustaining the availability of rare raw materials. Raw materials can be recycled from mining, processing, and commercial waste streams to ensure reliable, secure, and sustainable access to them.

Future growth of Electric vehicle manufacturing requires not only an expansion of the extraction of key minerals, but also of the entire EV value chain. This spans battery metal processing and refining, cathode and anode manufacturing, separator manufacturing, cell production, battery assembly and, finally, the assembly of electric vehicles. All these industries need to expand rapidly to avoid bottlenecks that would slowdown the transition to full electric mobility.