Numerous studies have made comparisons, from the one carried out by the International Council on Clean Transportation (Icct) to the one commissioned in 2022 by the Ministry of the Environment then led by Roberto Cingolani, and they all reach the same conclusion. Let's look at them through the most recent survey conducted by the specialized consulting firm Ricardo Group for the International Automobile Federation, organizer, among other things, of the Formula 1 World Championship. The vehicles considered are gasoline (Icev-G), diesel (Icev-D), non-rechargeable gasoline hybrids (Hev-G), rechargeable gasoline hybrids (Phev-G), hydrogen electric (Fcev), battery electric (Bev). For each, emissions in grams of CO2 per kilometer were measured taking everything into account: vehicle production, fuel production, exhaust emissions during use, emissions related to maintenance and disposal.
From cradle to grave
The results show that even today the best vehicles for reducing CO2 over their entire life cycle are electric ones: 100 grams per km, compared to 267 for petrol cars, 197 for non-rechargeable hybrids, 166 for rechargeable hybrids, and 136 for hydrogen cars. It is true that in the coming years emissions from combustion engine cars will decrease thanks to the use of bio and synthetic fuels, but at the same time, with the use of energy increasingly produced from renewable sources, and technological advances in battery production and disposal, emissions from electric cars will also decrease even more significantly. In 2050, electric cars will emit a third less CO2 per kilometer than hydrogen cars, 86% less than petrol cars, 82% less than diesel cars, and 73% less than plug-in hybrids.
A crucial element in battery technology is energy density, that is, the amount of energy stored per unit of weight. Traditional combustion engines boast much higher values compared to the batteries used in electric vehicles. Fossil fuels reach an energy density of about 13,000 Wh/kg, while lithium-ion (Li-ion) batteries, among the most widespread in electrics, offer only between 150 and 180 Wh/kg, with the latest technologies promising 500 Wh/kg.
Manufacturers are refining the composition of lithium-ion batteries to increase their energy density, lifespan, and safety. On the cathode side, the traditional NMC (Nickel-Manganese-Cobalt) chemistry—the most common in electric vehicles—is evolving towards higher nickel and lower cobalt formulations, both to improve capacity and to reduce dependence on a costly and problematic material (cobalt, which is rare and often mined under ethically controversial conditions). For example, “low Co” NMC cathodes and the competing NCA (Nickel-Cobalt-Aluminum) chemistry are gaining ground, offering similar performance with less cobalt content. On the anode side, alongside traditional graphite, ultra-high capacity materials such as silicon are being experimented with: silicon anodes could offer a specific capacity about 10 times higher than graphite, significantly increasing battery range. The challenge with silicon is managing mechanical stress during charge cycles (silicon expands and contracts, degrading itself); however, techniques such as the use of nanostructures or silicon-carbon composites are showing progress in containing these problems. Another crucial innovation is the development of solid electrolytes (polymeric, inorganic, or hybrid) to replace the flammable liquid electrolyte currently used in Li-ion batteries. Solid-state batteries promise to be safer (no volatile solvents or risk of leaks) and allow the direct use of metallic lithium as the anode—metallic lithium has enormous capacity, comparable to silicon, without the structural limitation of the graphite host. This could drastically increase the specific energy of the cells. Problems such as the formation of lithium dendrites (filaments that can pierce the solid electrolyte causing short circuits) remain to be solved, but ongoing research is focused precisely on solid electrolytes and interfaces that prevent such phenomena. The first semi-solid lithium batteries or those with mixed electrolytes are expected on the automotive market around the middle of this decade, with several prototypes already announced by companies like Toyota, Nissan, and specialized startups.
Next-generation batteries
In parallel with the improvement of conventional Li-ion batteries, radically new battery chemistries are being developed, some of which could find application in stationary settings and in the vehicles of the near future. Among these, the following stand out:
Lithium-sulfur batteries (Li-S): use sulfur instead of expensive transition metals in the cathode, promising much lower costs and a very high theoretical capacity (sulfur can accept more electrons per gram than metal oxides). Obstacles such as short cycle life (due to the dissolution of sulfur compounds) are being overcome thanks to new materials for the cathode and electrolyte. Li-S technology is coming out of the labs: in 2024, the construction of the world's first lithium-sulfur battery factory was announced in the USA (in Reno, Nevada), with a $1 billion investment and a planned production capacity of 10 GWh/year. This indicates the growing maturity of this solution, potentially suitable both for long-range electric vehicle applications and for stationary storage where the cost per kWh is crucial.
Sodium-ion batteries (Na-ion): replace lithium with the more abundant sodium, maintaining a similar electrochemical operation. They typically have a lower energy density than Li-ion, but offer advantages in terms of cost and availability of raw materials (sodium is found in common table salt) and better performance at low temperatures. In 2023–2024, major Chinese manufacturers made significant progress: CATL launched the second generation of its Na-ion batteries, reaching 160–200 Wh/kg, and announced the first application on vehicles of the Chery brand, with a hybrid battery that combines sodium and lithium cells to offer over 400 km of range and 4C fast charging. According to the founder of CATL, sodium-ion batteries could cover up to 50% of the market currently destined for lithium-iron-phosphate batteries, becoming a competitive solution especially for affordable vehicles and low-cost stationary storage. Large-scale production of Na-ion is expected after 2025, but there is already a basic industrial supply chain ready to expand with growing demand.
🔋 CATL's sodium-ion batteries power the new Aito SUV with ultra-fast 12C charging! ⚡
⚡CATL has launched a "factory-in-factory" (FiF) production line inside the Seres plant in Chongqing, enabling real-time battery integration for the upcoming Aito SUV. This reduces component delays to less than 20 minutes and ensures same-day component delivery, revolutionizing the efficiency of electric vehicle production.
🔋 "Naxtra" sodium-ion battery: key specs Charging
✅ ultra-fast 12C: 10-80% charge in <10 minutes (for example, the 100 kWh pack handles a 1.2 MW charge).
✅ Extreme Weather Master: operates from -40°C to 70°C, ideal for Arctic winters or desert heat.
✅ Energy density: 175 Wh/kg, the highest in the world for mass-produced Na-ion batteries, able to compete with lithium LFP.
✅ Safety first: integrated "firewall" technology survives crush/puncture tests without fire/explosion.
Play
🚗 with the new Huawei Aito SUV: two versions
1️⃣ EREV (Extended-Range): uses CATL's "Freevoy" sodium-containing battery for a wider temperature range.
2️⃣ BEV (All-Electric): Equipped with CATL's Qilin battery (probably enhanced with sodium). 🔍 *Presented as a "high-volume car" (probably the new generation Aito M6 or M7), intended to "define the new luxury".
🌍 Why this matters
Cost collapse: the abundance of sodium reduces raw material costs by ~30% compared to lithium. Renewable Grid Boost: 12C charging enables solar/wind energy storage with instant grid balancing. The CATL-Seres-Huawei trio accelerates the commercialization of sodium-ion batteries while rivals lag behind.
🔮 What's next?
With mass production starting in 2025, sodium-ion technology could:
Democratize electric vehicles: ultra-fast charging makes EVs practical for apartment dwellers. Lithium challenge: CATL aims to capture 30~50% of the low-end ESS/EV market by 2027
Companies like BYD are also investing in this technology, a sign that sodium-ion is considered one of the most promising candidates to diversify the battery offering.
The low production costs and great abundance of raw materials make sodium-ion batteries a promising alternative to the much more widespread lithium-ion batteries. Despite this potential, the progress of the segment is hampered by two main challenges: the relatively low energy density, which undermines their competitiveness in the market; and the use of organic liquid electrolytes, with related safety issues.
To address these problems, research has focused on solid electrolytes, which are inherently safer and can increase energy density thanks to the use of metallic sodium anodes.
But the solution is still far off. Each solid electrolyte brings with it advantages and disadvantages. In many cases, one of the weaknesses to be solved is the low ionic conductivity. This challenge is now being addressed by sodium superionic conductors (NASICON) as electrode materials.
The latest advances in this particular field come from an international team of interdisciplinary researchers, including the Canepa Research Laboratory at the University of Houston. The group has found a simple way to synthesize a particular sodium superionic conductor NaxV2(PO4)3.
Unlike existing materials, this compound has a unique way of managing sodium, allowing it to function as a single-phase system. In other words, it remains stable while releasing or absorbing sodium ions, and thus during charging and discharging. At the same time, it delivers a continuous voltage of 3.7 volts compared to metallic sodium, higher than the 3.37 volts of existing materials.
Although on paper this difference may seem small, in terms of energy density the improvement is significant: plus 15%. Tests have shown that sodium-ion batteries with the new material boast an energy density of 458 Wh/kg compared to 396 Wh/kg for older sodium-ion batteries.
The key to its efficiency is vanadium (V), which can exist in multiple stable states, allowing it to store and release more energy. “The continuous voltage change is a key feature”, said Canepa. “It means the battery can operate more efficiently without compromising electrode stability. It's a game changer for sodium-ion technology.”
The implications of this work go beyond sodium-ion batteries. The synthesis method used to create NaxV2(PO4)3 could be applied to other materials with similar chemistries, opening up new possibilities for advanced energy storage technologies. This could in turn have an impact on the entire energy segment.
The results are published in the journal Nature Materials.
⚡ Revolutionary technology and advantages
✅ Extremely high safety and stability: the 3D structure of NFPP ([P₂O₇]⁴⁻ + [Fe₃P₂O₁₃] layers) withstands harsh weather and operates at extreme temperatures (from -40°C to 70°C) without cooling, which is essential for urban storage and electric vehicles.
✅ Record energy density: 400 Wh/kg achieved in NFPP-4.5 composites (compared to 130 mAh/g in standard NFPP), bridging the gap with lithium LFP.
✅ Extreme longevity: maintains 88% capacity after 2,000 cycles at 3°C, superior to most lithium chemistries.
✅ Fast charging: 80% capacity in 12 minutes (5C rate), thanks to the low internal resistance of sodium.
The team led by Junmei Zhao, a researcher at the Department of Green Chemical Engineering Research of the Institute of Process Engineering of the Chinese Academy of Sciences, has improved the reversible capacity and energy density of iron-based phosphoric acid pyrophosphate cathode materials by stimulating inert sodium iron phosphate. Sodium ferrous phosphate (NaFePO4, NFP), sodium ferrous pyrophosphate (Na2FeP2O7) has three-dimensional ionic channels, but its theoretical capacity is low and it is unstable in air due to its low potential; NFPP-4.0 has a theoretical capacity of 130 mAh/g, a voltage of nearly 3.1 V, and is stable in air. It has been widely studied in recent years. However, due to structural defects, its actual capacity is lower than the theoretical one, so it has become essential to further improve the actual capacity of NFPP-4.0. The study found that during the preparation of NFPP-4.0, the addition of a certain amount of NFP can effectively stimulate the inert NFP. The new optimized NFPP-4.0 is Na 4.5 Fe 3.5 (PO 4 ) 2.5 P 2 O 7 (NFPP-4.5), that is, NFP/NFPP-4.0 is 0.5:1. Experimental results show that the reversible capacity of NFPP-4.5 is 130 mAh/g and the energy density is 400 Wh/kg. X-ray diffraction confirms that NFPP-4.5 is a symbiosis of NFPP-4.0 and NFP, in which NFP nanocrystals are continuously distributed in the crystalline domain phase of NFPP-4.0 and are wrapped by NFPP-4.0. A large number of transition regions at the grain boundaries favor the cross-transmission of sodium ions, thus effectively activating the electrochemical activity of inert NFP. The study found that during the charge and discharge process, NFP underwent an amorphization process during the first charge cycle, then passed into the amorphous state, confirming that the activation of NFP is the key to the high capacity of NFPP-4.5. The researchers brought this material to the kilogram level and the assembled soft-pack batteries achieved excellent rapid charging and cycling performance. Compared to 0.1 °C, even under fast charging conditions at 5 °C, the soft-pack battery can still achieve a reversible capacity above 80%. After 2,000 cycles at 3 °C, the capacity retention rate exceeded 88%, which presents application prospects. On March 28, the research results were published in the Journal of the American Chemical Society.
🚀 Key milestones of industrialization (2024-2025)
1️⃣ Scalability of mass production:
Puna Energy: management of 100-ton pilot production lines and 10,000-ton mass production lines.
Yinna New Energy: construction of 10,000-ton lines (launched in August 2024) with guaranteed orders for over 1,000 tons.
Jiana Energy: expansion of capacity from 100 tons/year to 10,000 tons.
2️⃣ Standards and investments:
The Chinese MIIT has added NFPP to its industrial standardization program for 2024, accelerating quality control.
Cost collapse: mass production will bring prices down to about ¥24,000/ton ($3,300) by 2025.
🌍 Market applications are taking off
ESS and renewable energy: the low cost ($150/kWh) and safety of NFPP are ideal for grid storage (e.g., the 10 kWh systems of the Dalian Institute).
E-Bike and micromobility: dominate the Chinese 2W/3W market with performance at -20°C and a lifespan of 5 years.
Electric vehicles: competing with LFP through 5C charging and deeper discharge without degradation.
🔮 What happens next?
2025-2027: NFPP will acquire 30-50% of the ESS/low-range electric vehicle markets as production scales up.
Cutting-edge leaps in technology: anode-free projects (over 200 Wh/kg) and hybrid cathodes (e.g., Mn-doped) will bridge energy gaps.
Global expansion: Southeast Asia and Europe are betting on NFPP to disrupt lithium supply chain dependence.
The hydrogen match
All things considered, only the hydrogen car comes close to the emissions of the car recharged at the power outlet, because it emits water vapor from the exhaust. The problem is that producing hydrogen requires a lot of water and a lot of energy . "In the hydrogen electric car I use energy to produce hydrogen through water electrolysis, then I have to fill up with hydrogen, which is then used to produce the energy to move the car – says Nicola Armaroli, research director at the CNR – while in the electric car I take the energy and use it directly to charge the car battery: basically, to travel the same kilometers, it takes three times the energy of an electric car recharged at the outlet." So, assuming that the energy used for both technologies is produced from renewable sources, the process to produce hydrogen is less efficient. There are currently 2 hydrogen models on the market, the Toyota Mirai (€76,800) and the Hyundai Nexo (€78,300), and a total of 65 cars circulate in Italy. Since the beginning of the year, only one has been sold (Acea data) and there are currently two hydrogen distributors, in Mestre and Bolzano. The National Hydrogen Strategy, November 2024 provides for the construction of at least 40 stations by 2026. However, the same document states: "Light road transport cannot be considered a 'hard-to-abate' sector, as the full electric solution is already a consolidated reality. The much lower energy efficiencies and consequently higher operating costs do not make this type of solution competitive, which can, however, have applications for ships or buses and heavy vehicles".
Synthetic fuels
These are called e-fuels and, to produce them, you start from hydrogen and then combine it with CO2 captured in large industrial plants. You get a low-emission fuel because the carbon dioxide emitted during combustion is equal to that used for its production. A long, very energy-intensive and expensive process: today e-fuels cost between 3 and 5 euros per liter. At the moment there are still no e-fuel cars but, after Germany's fierce battle, the EU has given the green light to the production of internal combustion engines even after 2035, provided they are powered with this type of fuel. However, it will be a niche application, to satisfy those who do not want to give up supercars with combustion engines. And in fact Porsche is investing in Punta Arenas, in Chilean Patagonia, where it has a small plant that produces 100 tons a year of synthetic fuel. To get an idea of the scale: every year we use 2.5 billion tons of fuel for road transport worldwide.
The limit and scams of biofuels
Italy is betting heavily on biofuels which, however, are not all the same, as clearly specified in the European directives. They can be defined as "bio" if produced locally with waste materials (from farms, industry or agriculture); if, on the other hand, land is taken away from agricultural crops to plant corn or soybeans to be converted into biomass, the story changes. The biofuels placed on the market in Italy are largely produced with raw materials that travel thousands of kilometers: 541 thousand tons come from China, 217 from Indonesia, 101 from Malaysia. Moreover, of dubious origin. Let's take biofuels produced with Pome, a residue from palm oil production and for this reason considered sustainable. But, according to the European association T&E, the amount of Pome available on the market is 1 million tons per year, while the declared consumption for biofuel is two million tons. This means that palm oil is being passed off as Pome and used to produce biofuels. So it is no longer a waste product, but comes from dedicated crops. The certain fact is that "good" biofuels are inevitably in limited quantities. According to Transport & Environment, those actually produced from waste and residues would only be enough to power about 5% of vehicles circulating in Italy.
The fact remains that under current European regulations, biofuels cannot be used to power cars with internal combustion engines from 2035. According to the European court of auditors "most biofuels could be used for aviation and maritime transport".
In conclusion, if we talk about planes and ships, electric is either disadvantageous or does not work. Think of intercontinental flights: there is no suitable battery to make them possible. The battery is not always the best solution even for intercity buses, not surprisingly hydrogen buses sold in 2024 were 903, 1,466 in the first half of 2025. So for heavy transport everything will be less impactful than fossil fuels and, therefore, biofuels, e-fuels, hydrogen are welcome. If instead we talk about cars, as we have seen, electric ones beat the others in reducing CO2 emissions. They are also more efficient. According to the Transport & Environment survey, today 77% of the energy generated by the electric car is converted into movement, while in the gasoline car only 20%, the rest is lost. Along with PM10 particles that make city air unbreathable. Looking to 2050, the efficiency of electric will rise to 81%, compared to 42% for hydrogen cars and 16% for e-fuels. Let's not use the smokescreen of technological neutrality to continue ideological wars. The transition will be difficult, but inevitable, and will have a price. Decisions will then have to be made that bring together environmental, economic and social issues. But telling citizens things as they are.
