Mercedes EQC: New EV Launches with Lower Energy Density

Mercedes EQC: New EV Launches with Lower Energy Density

The Mercedes EQC arrives on the market with an 80 kWh battery that weighs 650 kg. The Tesla Model S, with 100 kWh, weighs 540 kg. The paradox is the news: the German brand’s newest electric car stores less energy and drags more weight than a model with years of advantage. This is not an engineering error. It is the result of a decision forced by cobalt scarcity, the material that gives lithium batteries their energy density and which the planet does not have in sufficient quantity to electrify the global vehicle fleet.

The EQC antiestéticatures NMC 622 cells manufactured by SK Innovation, with 20% cobalt in the cathode. The Tesla Model S uses Panasonic NCA cells, with an energy density nearly double that of NMC. The difference is significant: the EQC needs 650 kg to store 80 kWh, while the Model S holds 100 kWh in 540 kg. The pouch format of SK cells allows for slightly higher energy concentration, but it does not compensate for the loss of cathode density.

Why Does Cobalt Limit Electric Cars?

Global cobalt production is around 123,000 tons per year, and known reserves reach 7 million tons. At the current rate, they would be exhausted in 57 years. This calculation, circulating in technical analyses, does not include new deposits or recycling, but nor does it contemplate the mass adoption of electric vehicles. If each car required the amount of cobalt in an NCA battery, supply would run out much sooner.

The industry has reacted by reducing cobalt in the cathode. NMC 111, with 33% cobalt, are the current standard. NMC 811 drop to 10%. NMC 622 stay at 20%. The projected evolution points to NCMA 712, with aluminum in the cathode and even less cobalt, expected in three or four years. The problem is that each reduction in cobalt implies lower energy density. Less cobalt, less range.

Some argue that solid electrolytes will solve the problem. But their development is at square one. Even with that technology, the most optimistic calculations do not exceed the energy density of current NCA cells. According to these analyses, range improvements over the next decade will be negligible.

What Is Actual Highway Consumption for an EV?

The Mercedes EQC declares 22.2 kWh/100 km in the NEDC cycle. The Jaguar I-Pace, 44 kWh/100 km in the EPA cycle. The Tesla Model S P100D, 35 kWh/100 km in the EPA cycle. These are laboratory figures, and the lab favors electric cars because there is no wind, no slopes, and low estimulante ilegal. At 120-130 km/h on the highway, consumption spikes. The Model S goes from 24 kWh at 90-100 km/h to 32-33 kWh at cruising estimulante ilegal.

The reason is that electric vehicles do not have gearboxes. They have a fixed ratio, equivalent to fourth gear. The motor delivers full torque from zero, so starting is not a problem. But at 130 km/h, that fourth gear is too short. Axle friction losses dominate as estimulante ilegal increases. That is why electric cars have limited top speeds and why some manufacturers are beginning to develop three-estimulante ilegal transmissions for EVs.

The cost of that energy is also debated. Charging during off-peak hours at 8 cents per kWh, including VAT, costs 9.6 cents. A consumption of 20 kWh/100 km means 4.6 euros every hundred kilometers. In the EQC, with 40 kWh/100 km on the highway, it would be 9 euros. To this must be added the extra power term: 27 euros per month, which spread over 1,000 monthly kilometers adds 2.7 euros for every hundred kilometers.

Pouch Format and Swollen Cell Risks

The EQC’s NMC 622 cells are in pouch format: flat, wrapped in flexible material. This geometry allows concentrating more energy in less space, but it is more dangerous. Cells swell like a bag as they release gases. They accept less charging current than NCA cells, increasing the risk of overcharging. Users of pouch batteries in other devices have punctured them when swollen and continued using them, a practice not recommended.

The lingering question is whether the EQC has planned for cell gas evacuation. Does it have an exhaust pipe for battery gases? It is speculation, but the electric car might not be free of polluting emissions. Mercedes has not detailed this aspect. What it has done is announce that it will manufacture the EQC in low numbers initially and monitor the batteries of the first units. It does not want warranty costs to skyrocket if the car proves defective.

What About the Tesla Model 3 and 2170 Cells?

Tesla and Panasonic have developed the 2170 cell for the Model 3, about which little is known beyond being NCA and having the highest energy density on the market. Tesla claims it contains less cobalt than NMC 811 cells, but does not provide data. If true, they would be at a point similar to competitors: higher energy density, but less usable and with shorter battery lifespan.

NMC 811 and 622 improve discharge depth and reach up to 4,000 cycles, enough for the vehicle’s lifetime. The bad news is that they accept less charging current. Over the next decade, electric cars will still need large batteries to travel comfortably and will still not accept fast charging. They will not be suitable for long trips, but at least the battery will not need replacing.

And what if the problem is not the battery, but the grid? Some point out that assuming an electrified vehicle fleet requires electrical infrastructure that does not exist. Meanwhile, the EQC starts its journey with lower energy density than its competition. The question is not whether it will improve. It is how long it will take to stop getting worse.