EV Batteries. Welcome back to the Borates Today podcast. Each week we cover a topic that is relevant to the industry and timely. We cover the latest industry news. Who are the key players in the sector? What are the latest trends, driving demand and supply for boron. What is the science behind boron and who’s doing valuable research into new boron applications and benefits?
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In today’s podcast, we’re going to look at electric vehicle batteries. Electric vehicle batteries are rechargeable batteries that power electric cars bikes and scooters. They are specifically designed to give power over a sustained period and are deep cycle batteries. Lithium-ion batteries are usually used in EVs. The relatively higher power-to-weight ratio makes them ideal for powering electric cars and bikes.
Electric Vehicle EV Batteries
First off, how does an electric vehicle battery function? Whereas internal combustion engine cars obtain their energy from gasoline or diesel combustion, an electric vehicle draws power directly from a large battery pack.
These packs are similar to a larger version of the lithium-ion battery in your phone. EVs as they are called, don’t use a single battery, like a phone but rather a pack made up of thousands of individual lithium-ion cells that work together. When the car is charging, electricity induces chemical changes inside the battery.
These changes are reversed when the vehicle is on the road to generate electricity.
What about the technology used in electric vehicle batteries?
These EV batteries go through cycles of discharge while driving and charge when the car is plugged in. The amount of charge electric vehicle batteries can hold decreases as this process is repeated over time. This reduces the range and time required between charging journeys. The majority of battery manufacturers provide a five to eight-year warranty on their products.
Current predictions suggest that electric vehicle batteries will last between 10 and 20 years before needing to be replaced.
The connection between a battery and the car’s electric motor is surprisingly simple. The battery connects to one or more electric motors, which drive the wheels. When you press the accelerator, the car immediately supplies power to the motor, gradually absorbing the energy stored in the batteries. Because electric motors also function as generators, when you take your foot off the accelerator, the car begins to slow down by converting its forward motion back into electricity. This occurs more strongly if you apply the brakes. this regenerative braking recovers energy stored in the battery. thus extending the vehicle range.
Lithium-ion Batteries
Lithium-ion batteries are lightweight, high-capacity batteries commonly used in electronic devices, such as laptops, mobile phones, cameras, video game consoles, GPS receivers, digital music players, and electric cars and bikes. These batteries have a high energy density, which means that battery manufacturers will be able to save space by decreasing the overall size of a battery pack over time.
Lithium is used. It’s also the lightest of all metals, which further contributes to the compactness of the batteries. Another key benefit of lithium-ion batteries is that they do not contain lithium metal. Instead, they rely on ions to create an electric charge. This makes it much safer than other batteries that use lithium metal, which can be highly volatile.
How about the use of boron in lithium-ion batteries?
Lithium-ion batteries rely on graphite as an anode material due to its low cost and good properties such as high electrical conductivity and stability. However, lithium deposition can cause issues that lead to short circuits and safety concerns at high charge rates. Borate surface coating may safeguard against lithium deposition improving the overall stability of the battery which serves as a boundary between electrode and electrolyte
One of the primary challenges of improving lithium-ion batteries is producing a highly ordered crystalline graphite structure through high-temperature heat treatment requiring temperatures in the 3000 degrees centigrade range. Still, this process can be expensive and energy-intensive. However, adding borate before graphitization enhances electric chemical properties without increasing temperatures as high as with standard gravitization processes.
For increasing, crystallinity boron is incorporated into the crystalline structure of graphite at higher temperatures that activate greater alignment and change the electronic structure. Boron acts as an electronic acceptor resulting in a specific capacity of 437 milliamps per gram, higher than the standard maximum for pure graphite- around 372.
There is much discussion about recycling electric vehicle batteries. Although enabling a second life application can extend battery life, electric vehicle batteries must eventually be recycled. In many countries, BEV technologies lack a well-established recycling framework, making BEVs and other battery-powered electrical equipment a considerable energy expenditure, ultimately increasing CO2 emissions.
Let’s turn to the recycling aspects of EV batteries. There are five types of recycling processes currently in use. Pyrometallurgical recovery. Physical materials separation. Hydrometallurgical metal reclamation, a direct to recycling method and biological metals reclamation.
The pyrometallurgical process uses a high-temperature furnace to burn the battery materials with slag, sand, limestone, and Coke to produce a metal alloy. The materials produced are metallic alloys, slag, and gases. The gases are evaporated molecules from the electrolytes and by the components.
In physical materials separation, materials are recovered through mechanical crushing and using physical properties such as particle size, density, ferromagnetism and hydrophobicity. Sorting can recover copper, aluminum, and steel casing. The remaining materials known as black mass, are nickel, cobalt, and lithium.
The hydrometallurgical process separates the metal alloy into constituent materials. The slag, which is a metal mixture of aluminium, manganese, and lithium, can be reclaimed and used in the cement industry, for example. This method is highly adaptable and relatively risk-free. It can work with a wide range of batteries because no pre-sorting is required. And furthermore, the entire cell is burned. So the metal from the current collectors could aid in the smelting process. The energy absorption can be reduced by burning electrolyte sand plastics due to the exothermic reaction.
However, this process still necessitates a significant amount of energy. And only a limited number of materials can be reclaimed. The cathode materials must be crushed to remove the current collection for the hydrometallurgical process. The cathode materials are then leached by aqueous solutions to extract the desired materials from them.
As the name implies, direct capital recycling extracts the materials directly generating a cathode power that can be used as new cathode pristine material. This method includes the extraction of electrolytes using liquid or supercritical CO2. The cathode materials can then be separated after the size of the recovered components is reduced.
And as for the process of biological metals reclamation also known as bioleaching, employs microorganisms that selectively digest metal oxides. Recyclers can then reduce the oxides to produce metal nanoparticles.
Are Electric Vehicle Batteries Safe?
Manufacturers assure us that EV batteries are safe, installing smart management systems to prevent overheating and other issues. Batteries, however, do get warm during charging and discharging, but vehicles are designed to keep them cool.
High-performance EVs may have liquid cooling systems to assist the cooling. Despite this, there have been a number of instances of electrical vehicles catching fire but very few of these incidents were caused by battery failures. They’ve resulted from accidents that could have caused any car to catch fire such as the 2013 case of a Tesla Model S colliding with a large piece of metal at high speed. In response to the incident, which resulted in a minor fire, tesla CEO, Elon Musk stated that electric vehicle batteries contain only about a 10th of the energy of a tank full of fuel, which reduces the danger.
In fact, according to a 2017 study conducted by the US National Highway Traffic Safety Administration, the probability and intensity of fires caused by lithium-ion batteries were comparable to, or slightly less than that caused by conventional vehicles. As more electrical vehicles hit the road, we should be confident that they are as safe as traditional vehicles.
And that’s all from Borates Today. For more information on electric vehicle batteries, please refer to Borates Today, website. Meanwhile, thanks for listening.