Batteries vs Gas Alternatives: The Search for Sustainable Alternatives
The automotive industry is undergoing a transformative shift as it seeks sustainable alternatives to traditional gasoline-powered vehicles. As concerns over environmental impact and fossil fuel dependency grow, several alternative fuels and energy sources are emerging as viable options. In this article, we’ll take a look at the various types of batteries available to power EVs – as well as other alternative fuels.
We’ll list the pros and cons of the different types of technology, highlighting their upsides and downsides – and have a look at why battery electric vehicles (BEVs) are becoming so common, and likely the answer to replace gas powered vehicles long term.
Electric Vehicle Batteries: Powering the Future
Lithium-ion batteries in electric vehicles (EVs) represent the future of passenger transportation due to their unparalleled efficiency, environmental benefits, and technological advancements.
Unlike hydrogen, CNG, and bio-fuels, lithium-ion batteries offer a cleaner and more sustainable solution, significantly reducing greenhouse gas emissions, and reducing reliance on fossil fuels. Long-term, they can also be recycled. The rapid advancements in battery technology have led to increased energy density, faster charging times, and longer driving ranges, making EVs more practical and appealing to consumers.
Furthermore, the growing infrastructure for electric charging stations and the decreasing cost of lithium-ion batteries make EVs a more accessible and cost-effective option. As governments and industries worldwide push for greener transportation solutions, lithium-ion batteries stand out as the most viable choice.
Lithium-Ion Batteries: Lithium NMC and Lithium NCA Chemistry
Currently, the main lithium-Ion batteries break down into two different types. The first type consists of primarily lithium NMC (nickel-manganese-cobalt) and lithium NCA (nickel-cobalt-aluminum). These mixes make the batteries more power-dense, and therefore deliver the greatest range and power for EVs.
Pros include:
- High energy density: Li-ion batteries offer a high energy density, and the energy density increases roughly 5-8% per year, enabling longer driving ranges.
- Efficiency: The batteries are highly efficient in terms of energy storage and converting back to usable energy. Lithium-ion chemistries are also offering greater charging speed.
- Long lifespan: With proper management, Li-ion batteries have a long operational lifespan.
Cons include:
- Cost: The production and materials for Li-ion batteries have been very costly, though prices have dropped significantly over the past year.
- Capacity degradation: Over time, the capacity of Li-ion batteries degrades, when frequently charged to and left at a high rate (90%+) for an extended time. Along with lithium batteries being at high temperatures for extended periods, this is why good thermal management is so important in EVs.
- Safety risks: There is a risk of overheating and thermal runaway, which can lead to fires.
But while lithium NMC or lithium NCA chemistries were the first to market, and still a popular choice, they are expensive – and usually reserved for higher end EVs or ones that need a lot of range.
Lithium Iron Phosphate (LFP) Batteries
The second type of EV battery is lithium iron phosphate (LiFePO4) batteries, also known as LFP batteries. Think of LFP batteries as the diesel engine of the EV era. Generally, they are not as power dense and maybe not ideal for a sports car, but they are very reliable and safe overall.
Pros include:
- Safety: LFP batteries are known for their excellent thermal and chemical stability, reducing the risk of overheating and fire.
- Long lifespan: These batteries often offer a longer cycle life compared to other lithium-ion batteries.
- Environmental impact: LFP batteries are considered more environmentally friendly due to the more stable and less toxic materials used.
- High discharge rate: LFP batteries can deliver high discharge rates and can generally take a higher DC charge rate when the battery is at a higher state of charge (SoC), compared to lithium NCA or NCM chemistries.
- Lower cost: The upfront cost of LFP batteries are generally much less compared to the other lithium-ion battery types.
Cons:
- Lower energy density for given weight: Compared to other lithium-ion batteries, LFP batteries have a lower energy density, meaning they store less energy for their size and weight.
- Challenges in cold weather: While these challenges can be overcome, LFP batteries do generally have issues performing at peak performance in cold weather compared to NCA or NCM lithium-ion chemistries.
Solid-State Batteries
A new technology on the horizon has been receiving a lot of attention recently: solid-state batteries. As the name suggests, solid-state batteries do not need liquid electrolytes. Their basic structure is the same as a lithium-ion battery, but because they do not use liquids, solid state battery packs can be lighter, safer, and much more compact.
Pros include:
- Enhanced safety: Solid-state batteries have a reduced risk of fire and overheating.
- High energy density: They offer the potential for much higher energy density than lithium-ion batteries.
- Longer lifespan: Solid-state batteries are more stable and have a longer lifespan.
Cons include:
- High production costs: Currently, solid-state batteries are expensive to produce.
- Early development stage: Solid-state batteries are still in the early stages of commercialization, with limited availability. They are consistently referred to by some automakers as “five to 10 years away.”
- Complex manufacturing: The production process for solid-state batteries is complex, expensive and still early days.
Hydrogen Fuel Cells and Hydrogen as a Fuel Source
For more details, check out my previous article about the challenges of Hydrogen for passenger vehicles. However, at a high level, hydrogen has these pros:
- Refueling speed: Hydrogen vehicles can be refueled in a matter of minutes, similar to conventional gasoline vehicles.
- Energy density: Hydrogen boasts a high energy density, offering longer driving ranges compared to most battery-powered EVs.
- Zero emissions: Hydrogen fuel cells produce only water vapor as a byproduct, making them an environmentally friendly option.
Hydrogen’s cons include:
- Infrastructure challenges: The availability of hydrogen refueling stations is limited, hindering widespread adoption.
- High Production costs: Currently, hydrogen production is expensive and energy-intensive.
- Storage and transport: Hydrogen requires special handling and storage solutions, which adds to the complexity and cost.
- Currently, most hydrogen is not produced in a very environmentally friendly way.
- Concerns of using water via electrolysis to get the hydrogen.
- Hydrogen is the most common element, but is rarely by itself, which adds to the challenge of accessing it as a fuel.
- Perception: Safety concerns among the public has been a perpetual uphill battle for hydrogen.
Compressed Natural Gas (CNG)
Some vehicles offer the choice of compressed natural gas (CNG) which can be used as an alternative to gasoline. CNG is commonly used in taxicabs and some delivery vehicles.
Pros include:
- Lower emissions: Even though it is a carbon-based fuel, CNG vehicles emit fewer pollutants compared to gasoline and diesel engines per mile.
- Cost-effective: Natural gas is often cheaper than gasoline, providing cost savings for drivers.
- Abundant supply: Domestically in North America at least, natural gas is more available than ever, and less susceptible to price fluctuations than oil.
- Infrastructure: Existing natural gas infrastructure means that it is easier to move and access as a fuel source.
However, CNG has some cons as well:
- Limited infrastructure: The number of CNG refueling stations is limited, especially outside urban areas. While the infrastructure is much more abundant and much further along than hydrogen infrastructure, it is still very limited. Especially when compared to existing electrical infrastructure.
- Shorter range: Similar to how hydrogen has great energy density by weight, it is not as efficient by volume. CNG vehicles typically have a shorter driving range compared to gasoline vehicles.
- Storage issues: Also like hydrogen, CNG requires large, heavy tanks to help with crash safety of the vehicle. Unfortunately, this further reduces overall vehicle efficiency and storage space.
Biofuels: Renewable Energy on the Road
Biofuels made from renewable resources can help reduce emissions, and work in conventional engines, meaning drivers don’t have to adapt to new technology.
Pros include:
- Renewable resource: Biofuels, such as ethanol and biodiesel, are made from renewable resources like crops and waste materials.
- Reduced carbon footprint: Biofuels generally produce fewer greenhouse gases compared to fossil fuels.
- Engine compatibility: Many biofuels can be used in existing internal combustion engines with minimal modifications.
However, biofuels do have some drawbacks as well:
- Lower energy density: Biofuels have a lower energy density than gasoline, which can result in higher fuel consumption.
- Land use concerns: Large-scale biofuel production can lead to deforestation and compete with food crops for land and resources.
- Emission of pollutants: While cleaner than fossil fuels, biofuels still produce some emissions, though they are typically less harmful.
- Cost: Generally biofuels are about double the cost of gasolne, due to being lower volume of production and additional work needed for production.
How Efficient are Alternative Fuels Compared to EV Batteries?
When it comes to efficiency and emissions, hydrogen fuel cells and CNG vehicles are more efficient and produce fewer emissions than traditional internal combustion engines. However, they generally lag behind electric vehicles. Electric motors, in conjunction with batteries, particularly Li-ion batteries, are very efficient, transmitting the majority of the energy in the battery to the wheels. Biofuels, while renewable, still produce some emissions and have lower energy density compared to both hydrogen and electric options. Conventional engines have many reciprocating parts, and efficiency losses occur within the engines and transmissions in route to the wheels.
Charging Infrastructure Exceeds Hydrogen and CNG
Electric vehicles benefit from a growing network of charging stations, making them increasingly convenient for consumers – plus, EV owners can charge their vehicle at home, significantly extending the available infrastructure, and improving convenience.
In contrast, hydrogen and CNG refueling infrastructure is still limited, posing a challenge for widespread adoption. Biofuels have the advantage of utilizing existing gasoline distribution networks, albeit with some modifications.
Alternative Fuels: Cost and Availability
Lithium-ion batteries are becoming more cost-effective due to technological advancements, economies of scale, and material costs dropping. Biofuels and CNG are more readily available – but they face limitations in terms of energy density and vehicle range. Hydrogen, however, faces probably the most physical limitations of its ability to power passenger vehicles in the future, along with other logistical headwinds.
Conclusion: The Future of Sustainable Driving
The transition to alternative fuels and energy sources for passenger vehicles has been a complex, yet needed endeavor. As the automotive industry continues to innovate and develop these technologies, the choice between them will depend on a range of factors, including infrastructure, cost, driving range, and environmental impact. The future of passenger vehicles seems to be electric, paving the way for a more sustainable and efficient transportation ecosystem.
