May 30 - Tesla's advanced battery research team has worked with Jeff Dahn's battery lab at Dalhousie University to develop a new type of nickel-based battery with a very long life.
A paper published by Dahn and his team in the Journal of the Electrochemical Society shows that the new nickel-based battery can last 100 years if kept at 25 degrees Celsius.
It is said that this new battery has many advantages to compete with the durability of LFP (lithium iron phosphate), while the energy density can be even higher than that of other nickel-based batteries.
Compared with the general power battery, the higher energy density of the battery occupies less space in the vehicle, enabling the car to drive farther miles.
In the field of electric vehicles, Tesla has always been treated as a wind vane. Behind this, in addition to its amazing sales performance, but also because Tesla in the power battery and other key parts of the car in the industry leader, the Tesla researchers made a power battery can be used for 100 years, can be said to be a great technical breakthrough.
First, the battery nearly 2,000 charge and discharge cycles without decay life of up to 100 years
Jeff Dahn is a professor at Dalhousie University in Canada, and has been a research partner of Tesla since 2016, whose research direction is to improve the energy density and life of lithium-ion batteries, as well as to reduce their cost; Dahn is considered one of the pioneers of lithium-ion batteries.
Previously, Dahn has announced his intention to develop a "million-mile battery" and has been testing batteries based on his adapted chemistry since October 2017.
In a paper recently published in the Journal of the Electrochemical Society, Dahn and his team tweaked the composition of the NMC battery, and after 4.5 years of continuous charge and discharge cycles at room temperature (25 degrees Celsius), the researchers found that the battery had only 5% degradation, meaning that the battery could provide 4 million miles (about 6,437,000 km) of range for an electric vehicle while providing a service life of This means that the battery can provide 4 million miles (6,437,000 km) of range for an electric vehicle, and can last up to 100 years.
The team modified a conventional NMC 532 battery by converting the cell from a polycrystalline cathode to a single crystal cathode that does not break down rapidly during charge and discharge cycles.
After experiments, the team found that the modified NMC 532 battery showed no capacity loss after nearly 2,000 charge/discharge cycles, and their paper concluded that the new NMC 532 battery has a life expectancy of 100 years.
The orange diamond in the graph indicates that the NMC 532 chemistry does not show a reduction in capacity (after 2000 cycles of discharge).
In his conclusion, Dahn noted that at equivalent cell potential, the NMC 532 cell did not contain as much graphite as the conventional NMC cell, operating at balanced low voltage with voltage cycling to 3.65V and 3.8V.
At all set cycling temperatures, the low-voltage NMC 532 has better capacity retention compared to the LFP cell and the NMC 532 cell and operates at voltages up to 4.2V.
Dahn also compares the ternary lithium battery (NMC 532) in the paper to the LFP battery, which is the battery used in the standard range version of the Model 3 currently manufactured by Tesla in its Shanghai factory.
Although the energy density of the LFP battery is lower than the ternary lithium battery, but its lower cost, more durable, stable and safer; in addition, the lithium iron phosphate battery can last up to 12,000 charge and discharge cycles, long life. Therefore, there are more and more electric vehicles are starting to choose LFP batteries.
The test results in the paper show that the life and volumetric energy density of the low-voltage NMC 532 battery exceeds that of the LFP battery.
In addition, Dahn also used the NMC 532 battery in contrast to LG Chem's current NMC 811 battery chemistry; the NMC 532 battery has a 5:3:2 ratio of nickel, manganese and cobalt cathode components, while the LG Chem NMC 811 battery has eight parts nickel, one part manganese and one part cobalt in the cathode.
Last year, Tesla Model Y changed from the original NMC 811 battery to LG Chem's NCMA battery; the NMCA cathode contains 90% nickel and the other 10% is cobalt, manganese and aluminum, so it is also called "high nickel" battery, compared with LFP or NMC 811, these products are expensive but have higher energy density. These products are more expensive than LFP or NMC 811, but have a higher energy density.
The battery developed by Dahn's team can combine the advantages of the above batteries, with higher energy density and longer battery life.
Second, the official cooperation with Tesla in 2016, the new battery will not be mass production for the time being
In June 2015, Tesla and Dalhousie University in Canada signed a preliminary cooperation agreement on battery technology research, at the time, Tesla described the partnership as, "Jeff Dahn is helping to develop lithium-ion batteries with longer life, higher energy density and lower cost, and this cooperation is ' a match made in heaven.'"
The collaboration officially began moving forward in 2016, and Jeff Dahn's battery research team also entered into an exclusive research partnership with Tesla.
Tesla may not put this new battery into mass production, according to foreign media outlet CleanTechnica. The researchers said the battery substance ratios are more costly compared to LFP batteries and may not have the power characteristics needed for electric vehicles, but are ideal for long-term energy storage.
Notably, Tesla itself has a solar energy storage business, and in Tesla's 2021 Impact Report, Tesla said it plans to complete its goal of deploying 1,500 GWh of energy storage systems by 2030 to help accelerate the global transition to sustainable energy.
The new battery developed by Tesla and Dahn's team, which has the characteristics of long-term energy storage, will perhaps also be used in Tesla's energy storage products.
Comparison of chemical composition of NMC battery and LFP battery
While it remains to be seen whether the results of their research will be mass-produced, the results of the collaboration are already being highlighted.
Tesla recently renewed its contract with Dahn's team, extending the partnership through 2026. Notably, last year Dalhousie University in Canada announced that two scientists, Chongyin Yang and Michael Metzger, have been named research chairs at Dalhousie University, and both scientists will join the university's exclusive collaboration with Tesla on power cells as new partners.
Chonggyin Yang is currently the Chair of Tesla Canada Research, where he leads a research group focused on developing high-performance materials for advanced lithium-ion battery applications.
Michael Metzger is focused on developing new methods to study the performance and lifetime of advanced lithium-ion, lithium metal, and desalted batteries to gain fundamental knowledge about new electrode materials and new electrolytes.
Conclusion: Ultra-high-life batteries bring greater development for electrification
The NMC 532 battery that Dahn has been testing promises another leap forward in battery technology.
But do electric cars really need batteries that last up to 100 years? Does an electric car need a driving life of 4 million miles (about 6,437,000 km)? As it stands now, the answer must be no. Looking at publicly available data, the average age of a car in the United States is 12 years. At 14,000 miles (about 23,000 km) per year, the average lifetime mileage of a car in the U.S. is 168,000 miles (about 270,000 km), while in Europe it is much less.
So in effect, the most obvious advantage of the new battery, which can support extra-long driving range, is to improve the efficiency of charging and discharging the battery, and perhaps will also be introduced as an energy storage product.
Tesla's mission is to accelerate the world's transition to sustainable energy, and with the continued development of new battery technology, Tesla's solar project also has a high energy storage approach.
At the same time on the other hand, with the rapid development of battery technology, the range and life of the power battery is greatly improved, the general trend of the development of electric vehicles is irreversible, and in the future, with the further development of battery technology, the complementary energy advantage of fuel cars will no longer exist, and full-scale electrification will come quickly.