SHINHOP laser

The technology of power lithium-ion batteries can be roughly divided into three generations, categorized by cathode materials: the first generation cathode materials and the first generation power lithium-ion batteries. In 2010, it was the first generation of power lithium-ion battery technology, primarily using lithium manganese oxide as the cathode material; the second generation of power lithium-ion batteries mainly used ternary lithium and lithium iron phosphate as cathode materials. Currently, both technologies have their advantages and disadvantages and need to continue to improve.
In the future, the technology of power lithium-ion batteries, in the long term, is solid-state batteries, while in the short term, it is the continuous innovation of existing battery technologies in materials. The materials for the positive and negative electrodes, electrolytes, and separators still have potential for further development and improvement. Due to the global shortage of cobalt resources, reducing cobalt in ternary batteries is a major trend. Additionally, there are different technical routes for reducing nickel and increasing nickel in ternary batteries; reducing nickel transforms ternary into binary lithium manganese oxide, while increasing nickel leads to high-nickel batteries, enhancing battery energy.
From the perspective of technological research and development, whether it is lithium iron or ternary, we have already seen the possibility of a 40% increase in energy density today, as well as the potential for further cost reduction, which means that the third generation of power lithium-ion batteries may appear within a few years.

What about the next generation of power batteries?

What is meant by the next generation of power lithium-ion batteries? Looking back at the development process over the past decade, battery technology has evolved rapidly. It is precisely because of the advancement in battery technology that the electrification of vehicles has been significantly accelerated. Overall, the technology of power lithium-ion batteries can be roughly divided into three generations, categorized by cathode materials: the first generation cathode materials and the first generation power lithium-ion batteries. In 2010, it was the first generation of power lithium-ion battery technology, primarily using lithium manganese oxide as the cathode material, with the typical vehicle being the Nissan Leaf, which has a range of about 200 kilometers on a single charge. Today, the first generation of power lithium-ion batteries has mainly been applied in low-speed vehicles and two-wheelers.
Today, when people buy electric vehicles, they always ask whether it is ternary or lithium iron. Both ternary and lithium iron batteries are second-generation power lithium-ion battery technologies, based on the second-generation cathode materials, namely lithium iron phosphate and nickel cobalt manganese (aluminum) ternary oxide cathode materials. Now, the range of electric vehicles on a single charge has more than doubled compared to the first generation, and the second generation batteries are currently in a favorable position. Lithium iron batteries are applied from large vehicles to small ones, from power to energy storage, while the range of pure electric vehicles driven by ternary batteries continues to increase, reaching 600-700 kilometers. Both ternary and lithium iron batteries have their advantages and disadvantages; lithium iron batteries have higher safety and lower costs, but their driving range is not long enough. Ternary batteries extend the vehicle's range but are still somewhat expensive, and safety needs further improvement, so we must continue to advance.
The next generation of power lithium-ion battery technology we are discussing now, in my understanding, is the third generation. What is the third generation of power lithium-ion battery technology? The long-term goal is solid-state lithium-ion batteries. In the short term, it is the continuous innovation of existing lithium-ion battery technologies in materials.
Is there still potential for cathode materials to advance? Yes. Starting from lithium manganese oxide, what else can be used as cathode materials? There are high-voltage spinel nickel manganese oxide and high specific capacity nickel oxide. Negative electrode materials can also move towards higher specific capacities.
However, the improvement from the second generation to the third generation of power lithium-ion battery technology is unlikely to lead to a doubling of range as seen from the first to the second generation. The expected increase in range from the second generation to the third generation of power lithium-ion batteries is about 50%, with costs decreasing by about 50%.
Therefore, in the third generation of power lithium-ion battery technology, the reduction in costs is more important compared to the improvement in performance such as range. If we want to reduce costs, which direction should materials develop? There are many types of ternary materials, but one thing is clear: reducing cobalt is a major trend. The global cobalt resources are indeed becoming scarcer. The situation with lithium resources is still unclear, as more lithium mines are being discovered, and there is more lithium in seawater.
Next is the issue of nickel. From the perspective of reserves, nickel may also become insufficient in the future. In power lithium-ion battery technology, there are also different routes for reducing nickel and increasing nickel. Reducing nickel transforms ternary into binary, such as nickel manganese lithium-ion batteries; increasing nickel involves making high-nickel batteries to achieve higher specific capacity for the materials. Next, I will discuss the two technical directions of reducing nickel and increasing nickel in power lithium-ion batteries.
The key material in the direction of reducing nickel is nickel manganese lithium. After replacing 1/4 of the manganese in the first generation of power lithium-ion battery cathode material lithium manganese oxide with nickel, the spinel structure remains unchanged, and the voltage of the resulting battery increases. When paired with graphite, the battery voltage can reach above 4.5V. As we know, the nominal voltage of lithium iron phosphate batteries is 3.2V, and that of ternary batteries is 3.6V. Achieving 4.5V means that the voltage has increased, giving the battery an advantage in energy density.
Today, the range of ternary battery models can reach over 700 kilometers, but their safety is slightly weaker, and the price is relatively high. The range of lithium iron phosphate models can also approach 600 kilometers, and they are somewhat cheaper. The key challenge for the third generation of power lithium-ion battery technology is how to achieve both a long range and ensure safety while also having a lower price. From a technical principle perspective, nickel manganese lithium-ion batteries have the opportunity to achieve longer ranges, higher cost-performance ratios, and greater safety, but high-voltage systems often have lifespan issues. How can we ensure that the batteries made from these materials have a long lifespan?
For nearly 20 years, we have been focusing on this issue. There is a viewpoint in the industry that carbonate-based electrolytes are not viable, but we believe they are. After more than a decade of research and testing, we still use solvents like ethylene carbonate and dimethyl carbonate to formulate electrolytes, and we still use graphite as the negative electrode, achieving better cycle life than high-nickel ternary batteries. This is true not only at room temperature but also at high temperatures, and experimental data has fully proven this.

How did we achieve this? In the past, nickel manganese lithium was difficult to apply practically because when charged to 4.9V, lifespan issues arose that could not be resolved. We achieved breakthroughs through special interface layer structural design, allowing the battery to maintain good lifespan even at high temperatures. In terms of materials, after more than 2000 charge-discharge cycles, there is still over 90% capacity remaining. For the entire battery, it also has a lifespan of over 2000 cycles, which is better than the batteries currently using high-nickel ternary materials.
In recent years, the R&D team of the Chinese Academy of Sciences, from Beijing to the Songshan Lake Material Laboratory in Guangdong, is conducting full-chain development of nickel manganese lithium-ion batteries, from material technology to electrode technology. The electrolyte is also undergoing some functional adjustments, mainly to overcome the significant drawback of nickel manganese lithium-ion batteries, which is the cycle life issue at high temperatures. Once the life issue is resolved, the advantages of this battery in other aspects are very obvious: high energy density, high rate performance, especially high rate performance at low temperatures, as well as cost advantages, and it is also safer.
From the chart, it can be seen that compared to today's lithium iron phosphate batteries, the same 100Ah battery can achieve an increase in battery density by replacing lithium iron phosphate with nickel manganese lithium, without changing the anode, keeping the basic composition of the electrolyte unchanged, and without altering the workmanship or casing. The battery capacity can still reach 100Ah, and the battery voltage has increased by 40.6%, resulting in a 40% increase in energy per unit volume, with a cost reduction of about 20% per watt-hour. This is the result of reducing cobalt and lowering nickel in materials.
Another technological development path is to increase nickel. Currently, there is a high enthusiasm in the industry for developing high-nickel cathode batteries, competing globally for nickel resources. By increasing the amount of nickel in the ternary battery cathode, the specific capacity of the positive material can be increased from 160 to 180, and further to 200mAh/g. However, there are also issues to be resolved: how to ensure good cycle life and stability when making high-nickel batteries.
With the support of the national key R&D program, the industry is accelerating the research and development of high-nickel cathode gradient materials. What is the limit? The limit is to achieve full nickel, completely removing cobalt, and making nickel lithium-ion batteries.
From the current research and development of third-generation battery technology, whether it is lithium iron phosphate or ternary lithium batteries, we can already see the possibility of a 40% increase in energy density and further cost reductions. For example, if the third generation of ternary batteries moves towards an upgraded version of nickel lithium, the energy density can be increased by about 40%, and the endurance can be improved from less than 700 today to 1000Wh/L; the energy density of iron lithium can also be increased by 40%, and the cost can be reduced by another 20%.
Looking further ahead, there are all-solid-state batteries, which are revolutionary technologies. The Ministry of Science and Technology's key R&D program for new energy vehicles hopes to develop all-solid-state batteries through innovative principles. When the next generation of 600Wh/kg batteries is produced, lithium-ion batteries will not only be able to power cars but should also meet the power needs of electric airplanes. This is my brief introduction; I welcome everyone to criticize and correct.