Battery structure and performance in electric vehicles
Types of electric cars
A revolution in the production and use of electric cars is coming. Since day by day to popularity Electric cars are being used on the roads of different countries, it is worth getting to know the types of electric cars available and know a little about the technology of using them.
What is an electric vehicle?
Electric cars use one or more electric motors for acceleration and driving. Depending on the type of electric vehicle, the electric motor or motors either assist the conventional internal combustion engine or provide the vehicle’s fuel source entirely. .
What are the different types of electric cars?
When we talk about electric cars, we generally refer to three main types of electric cars: hybrid cars, plug-in hybrid cars, and all-electric cars. .
Hybrid electric car
A hybrid electric vehicle combines a conventional internal combustion engine with an electric motor and a battery pack to reduce fuel consumption. Hybrid vehicles use the electric motor when the combustion engine is inefficient, such as when accelerating from a standstill. .
Hybrid electric vehicles are more similar to conventional combustion engine vehicles in that car owners can only charge them with fossil fuels, usually gasoline.
The technology in these cars is such that it automatically charges the battery through what is known as “regenerative braking” and activates the electric motor system when conditions are right. Therefore, drivers do not have to control the car’s battery charge or connect the cars to the power outlet .
Plug-in hybrid electric car
A plug-in hybrid electric vehicle combines a combustion engine with an electric motor and battery pack, like a hybrid car. But it comes with certain differences. Plug-in hybrids typically have larger battery packs and more powerful electric motors than hybrids because the electric system does much of the heavy lifting when driving. This means plug-in hybrids can also be driven in electric-only mode, turning off the combustion engine completely. .
Driving a plug-in hybrid electric vehicle is similar to driving a hybrid. Because the car automatically charges the battery and switches between the combustion engine and electricity based on the conditions. However, drivers have the option to fill the plug-in hybrid with both fuel and electricity. .
A plug-in hybrid electric vehicle can run on gasoline only if the battery is fully charged, and on battery power alone if all the fuel is used up.
All Electric Vehicle (BEV)
An all-electric car runs exclusively on electricity, and their electric motors draw power from internal battery packs. These cars do not have any form of combustion engine in their system .
Given that BEV They rely solely on electricity, they need batteries with much more capacity and output kilowatt-hours than hybrid electric cars and plug-in hybrids. This additional battery technology usually results in a higher cost BEVs are becoming more electric than other types of vehicles. BEVThey need charging to move. This can be done via a home charger or fast charging station or energy recovered with regenerative braking. .
Mild Hybrid Electric Vehicle (MHEV)
A mild hybrid electric vehicle from a 48-volt electric starter motor known as an integrated starter generator (ISG). It is known to use to supplement the performance of its combustion engine. In fact, in the technology of these cars, the integrated starter generator cannot accelerate the car by itself and only helps the combustion engine. Therefore, this category of cars cannot be considered fully electric cars .
Fuel cell electric vehicle (FCEV)
These cars are similar to all-electric cars in that they only use electric energy to move, but the way they store energy is very different. contrary to BEVs that store electrical energy taken from a charger, FCEV They generate their electrical charge through a chemical reaction that generally involves hydrogen. This means that FCEVs can be filled with hydrogen and do not need to be charged from the grid.
Electric vehicle battery performance
The most important factor that can cause the tendency towards the use of electric cars is undoubtedly the battery. Battery performance, production and supply all play a decisive role in the use of electric vehicles .
Although electric vehicles still constitute a small part of the market, the use of these devices has increased in recent years and the sales market is growing in global markets. So that the demand for all kinds of electric cars has reached its highest level .
But what is the reason for the acceleration of demand and production of electric cars? Consumer interest is increasing, driven in part by the environment. Extreme weather events make the effects of climate change more tangible .
Another undeniable reason is battery technology, which is advancing exponentially and making electric cars much more competitive. Many believe that with the development of battery technology in the coming years, the cost of owning an electric car will be equal to the cost of a combustion engine car. .
The battery technology of electric cars, their production, performance, and most importantly their availability is the most important factor that moves towards the use of electric cars now and in the future.
In addition to all this, electric vehicles are easier to maintain and cheaper to operate than combustion engines.
Electric vehicle battery technology
But is there anything holding this industry back now? What do electric car batteries look like now and what will they look like in the future?
It is said that battery life is one of the factors that prevent the rapid increase in sales of electric cars. Many potential buyers are unhappy with the limited range of today’s electric car batteries.
But many manufacturers now offer electric car battery warranties of up to eight years or 16,000 kilometers. Contrary to popular belief, an EV battery that is a few years old has about the same range as a new battery.
Despite the increased lifespan, technology remains the number one barrier to widespread adoption of electric vehicles. There are many challenges: range, cost, weight, charging time and charging infrastructure are among the many challenges that exist in the production of batteries.
Lithium ion batteries
You’re probably familiar with the term lithium-ion because most modern smartphones use this type of battery. Lithium ion is also the most common type of electric vehicle battery. The reason is that they have high strength compared to low weight.
This reduces the weight of electric cars and allows them to travel more distances. Also, lithium-ion batteries are better than other batteries in maintaining a full charge over time.
All lithium-ion batteries work the same way: energy is discharged and recharged. Because the electrolyte conducts the positively charged lithium ions between the anode and the cathode. What is different is their materials and chemicals. The three main cathode formulations today are nickel, manganese and cobalt (NMC); Nickel, cobalt and aluminum (NCA) and lithium phosphate (LFP).
Cathodes in the battery can improve or reduce the cell density of the battery and thus its performance. For example, electric car batteries made with nickel and cobalt have a higher energy density that provides more power and longer range.
But they have a shorter lifespan; Their capacity to hold a full and fast charge decreases. NMC/NCA batteries are also less stable. So there are safety issues. For example, they must be transported as dangerous goods. LFP batteries have a lower energy density that provides less power and range. However, these types of batteries have a longer lifespan and are safer and cheaper than NMC and NCA batteries.
In recent years, the energy density of LFP batteries has improved significantly. This has led automakers such as Tesla to consider using LFP for their shorter-range vehicles to lower the price and make them more attractive to buyers. Other electric vehicle manufacturers have announced similar plans. This will certainly have implications for international supply chains.
New battery technologies for electric cars
It’s safe to say that it’s an exciting time for battery research and development. One of the challenges faced by the battery industry is the lack of cheaper, more stable and more accessible materials. For example, cobalt is an expensive and limited resource. So scientists around the world are experimenting with low-cobalt or no-cobalt cathodes.
For example, in LFP cells, the coating on the cathode material is made of iron phosphate, which can do the same job as manganese/cobalt, but is still not quite up to the mark. This type of battery does not store much energy and does not provide much energy.
But not everyone wants a car that goes from zero to sixty in two seconds. This means that not everyone needs electric cars with premium batteries. Most people buy the most cost-effective solution to do what they want.
Currently, lithium iron phosphate can provide about 150 miles of actual range. Tesla’s Model 3 SR with LFP batteries has achieved a range of 391 km in real-world tests, which is a long distance for many people.
There are many scientists and startups who are looking for advances in chemistry to be able to produce batteries that cover all the functions in one place. It is worth mentioning that scientists consider sodium ion as a potential solution of the next generation. This formulation does not offer high energy density, but there are many potential applications such as use in e-bikes, scooters and electric city cars.
Solid state batteries
One of the technologies that has attracted a lot of attention is the solid state battery. Solid state batteries have at least twice the energy density of today’s lithium-ion batteries. They promise fast charging and enough power to outperform combustion engine cars on city streets and highways. And without flammable liquid electrolyte, they are safe and efficient. These are the key points of selling electric cars.
The biggest hurdle right now is production cost and scalability. If the industry can overcome these challenges, the use of solid-state batteries in electric vehicles could increase demand as buyers looking for power and speed see EVs as a viable option.
Battery charging
Charging time is a big issue, especially for commercial users of electric vehicles. For example, many of its last-mile delivery operations have used electric delivery vans that have a range of about 140 kilometers on a single charge. This amount of charging seems sufficient for this purpose. But in heavy transportation it is different and it should be possible to provide more power. As battery technology advances, it won’t be long before fleets of fossil fuel-free rigs travel long distances on the road network.
While the battery industry has made great strides in delivering higher range, battery cost and weight, innovations that reduce charging time seem to have lagged behind. Of course, fully charging the battery of electric cars in a few minutes may soon become a reality.
Stordata is developing a new technology that could revolutionize battery charging. They use existing lithium-ion battery technology and upgrade graphite components with silicon. The result is very fast charging, 482.7 km in just five minutes. When it comes to range, many battery manufacturers claim that they can make batteries that provide up to 1,500 km. Solid state and organic batteries can provide 2700 km. This distance is much longer than any combustion engine vehicle.
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