1. New energy storage is imperative
1.1. Energy storage relay electric vehicles, large-scale demand growth imminent
In 2021, global energy shortage and energy transformation in various countries are accompanied by each other, striving to coordinate and coordinate the green and low-carbon development and supply of energy. In response to climate change and other challenges, countries have proposed more ambitious carbon emission targets and developed and implemented a series of strategies and measures; Supporting policies related to the energy industry have also been introduced, and the national energy structure has been adjusted and optimized, with energy security issues becoming a focus; Governments around the world are facing challenges such as energy shortages and rising prices, and are taking measures such as price limits, subsidies, and tax cuts to minimize the impact of energy supply and demand conflicts and rising prices on the economy and daily life. As of April 20, 2022, over 130 countries and regions around the world have proposed the goal of net zero emissions or carbon neutrality. The European Union, the United States, Russia, Japan, and South Korea have successively introduced action plans for carbon peaking and carbon neutrality in 2021, accelerating the pace of extensive and profound economic and social systemic changes.
Against the backdrop of countries around the world proposing the goal of carbon neutrality and carbon peaking, the construction of the global carbon market has entered an acceleration period. The gradual maturity of the carbon market and the continuous rise in carbon prices have become the main driving force for various industries to increase investment in clean technology. To achieve emission reduction goals, vigorously developing renewable energy is an important path to achieve clean and low-carbon energy transformation, and it is also a consensus among countries around the world. China has also emphasized the importance of achieving the "dual carbon" goals in its 14th Five Year Plan. The "14th Five Year Plan for Renewable Energy Development" jointly issued by the National Development and Reform Commission, the National Energy Administration, and other nine departments on October 21, 2021, anchors the goal of carbon peaking and carbon neutrality, requiring a significant increase in the proportion of renewable energy. On the one hand, it is necessary to reduce the use of fossil fuels and further improve the electrification level in various fields such as industry, transportation, and heating. By 2025, the annual power generation of renewable energy will reach around 3.3 trillion kilowatt hours, improving the low-carbon electrification level of terminal energy use, and actively promoting the application of new energy vehicles in urban public transportation and other fields. By 2025, the sales of new energy vehicles will account for about 20%; On the other hand, in the power structure, it is necessary to gradually replace traditional thermal power with renewable energy such as photovoltaic and wind power: focus on deploying nine major actions, including the urban rooftop photovoltaic action and the "photovoltaic+" comprehensive utilization action, to achieve multi-channel energy storage. Compared to traditional thermal power, new energy resources have the advantages of no risk of depletion, safety and stability, and no pollution to the environment, making new energy power generation increasingly popular. With the gradual increase in the proportion of photovoltaic and wind power, the problem of instability in the power system has also emerged. Photovoltaic power generation mainly uses sunlight for power generation, which is greatly affected by weather. Unlike photovoltaic power generation, which has more obvious peak valley characteristics due to day and night differences and short-term fluctuations, the matching of wind power consumption is poor, and there may be consecutive days of strong or calm weather. As of the end of 2021, China's thermal power accounted for 71.1%, hydropower accounted for 14.6%, and nuclear power accounted for 5.0%. Wind power and photovoltaic power have shown significant growth compared to 5 years ago, accounting for 7.0%/2.3% of the country's electricity generation, respectively.
In July 2021, the National Energy Administration issued the "Guiding Opinions on Accelerating the Development of New Energy Storage" (referred to as the "Opinions"), which proposed to achieve the transformation of new energy storage from early commercialization to large-scale development by 2025. The "Opinions" pointed out the establishment of a capacity pricing mechanism for independent energy storage power stations on the grid side, and the research and exploration of incorporating the cost benefits of alternative energy storage facilities into the recovery of transmission and distribution electricity prices. Therefore, establishing a sound energy storage pricing mechanism and an effective "new energy+energy storage" project mechanism will become the key to breaking the situation in the future. By "peak shaving and valley filling", the power grid requires small peak shaving capacity of power generation equipment, which can improve the utilization rate of power generation equipment, and is beneficial for the safe operation and economic benefits of the power grid.
1.2. New energy storage is emerging in the wind, contributing to the dual carbon goal
As of the end of November 2022, more than 20 provinces require photovoltaic and wind power generation to be equipped with energy storage, with a configuration ratio of no less than 10%. Among them, Henan and Shaanxi require a configuration ratio of 20%. The configuration time is mostly 2 hours.
In the "White Paper on Energy Storage Industry Research 2022", according to CNESA's prediction, under conservative scenarios where policy implementation, cost reduction, and technological improvement have not met expectations, the cumulative scale of new energy storage in China will reach 48.5GW by 2026, and the market will show a steady and rapid growth trend. The compound annual growth rate (CAGR) from 2022 to 2026 is 53.3%; Under the ideal scenario of successfully achieving the energy storage planning goals, it is expected that the cumulative scale of new energy storage in China will reach 79.5GW by 2026. This means that from 2022 to 2026, new energy storage will maintain a compound annual growth rate of 69.2% and continue to grow at a high speed.
Traditional energy storage is widely used, but its disadvantages cannot be ignored. At present, traditional energy storage is the main form of energy storage in the energy storage market, among which pumped storage is a mature and efficient energy storage technology, which is the main way to solve the peak and valley difficulties of power systems on a large scale. It is widely used and accounts for over 70% of the world. It stores a large amount of energy, releases energy for a long time, and has mature and stable technology. In August 2021, the Comprehensive Department of the National Energy Administration issued a request for approval of the "Medium and Long Term Development Plan for Pumped Storage Energy (2021-2035)", proposing that the installed capacity of pumped storage energy in China will increase to 300GW by 2035. However, it is difficult to select a location for pumped storage, as it depends on the terrain; The investment cycle is long and the losses are high.
In response to the shortcomings of traditional energy storage, the National Energy Administration proposed on June 24, 2022 in "Improving the Construction Level of New Energy Storage" that "new energy storage has advantages such as fast response, flexible configuration, and short construction period. It can play an important regulatory role in the new power system with the increasing proportion of new energy, and is an important support for achieving carbon peak and carbon neutrality goals
According to the "2022 Energy Storage Industry Application Research Report" released by CNESA in April 2022, as of the end of 2021, the cumulative installed capacity of global energy storage projects that have been put into operation is 209.4GW, a year-on-year increase of 9%. Among them, the largest one is pumped storage, with a cumulative installed capacity of about 180.5GW, accounting for 86.2%, a decrease of 4.1 percentage points from the end of 2020. The cumulative installed capacity of new energy storage methods (excluding pumped storage and molten salt thermal storage, including lithium-ion batteries, lead-acid batteries, sodium sulfur batteries, compressed air, flow batteries, supercapacitors, and flywheel energy storage) is 25.4GW, a year-on-year increase of 67.7%, accounting for 12.2%. In new energy storage, lithium-ion batteries still dominate, with a cumulative installed capacity accounting for 90.9%; Compressed air energy storage accounts for 2.3%, and lead-acid batteries account for 2.2%; Sodium sulfur batteries account for 2.0%; The proportion of liquid flow batteries is 0.6%.
At the end of 2021, China's cumulative installed capacity of energy storage reached 46.1GW, ranking first in the world. Among them, the installed capacity of pumped storage is 39.8GW, accounting for 86.3%; The cumulative installed capacity of new energy storage reaches 5729.7MW, accounting for 12.5%, and the cumulative proportion of molten salt heat storage is 1.2%. In the new energy storage installation, the cumulative installed scale of lithium-ion batteries accounts for 89.6%, the cumulative installed scale of lead batteries accounts for 5.9%, compressed air energy storage accounts for 3.2%, liquid flow batteries account for 0.9%, and other electrochemical energy storage (supercapacitors, flywheel energy storage) accounts for 0.4% in total.
The future market space for new energy storage is foreseeable, and electrochemical energy storage and supercapacitors will face rapid growth in the coming years.
(1) Electrochemical energy storage
In an ideal state, the goals of "carbon peaking" and "carbon neutrality" are huge benefits for the energy storage industry. If there is a stable profit model, in the later stage of the 14th Five Year Plan, electrochemical energy storage will form another round of high growth. According to data from the Prospective Industry Research Institute, the installed capacity of electrochemical energy storage in China is expected to reach 55.9GW by 2025, with a CAGR of 70.5% from 2021 to 2025.
(2) Supercapacitor
Compared with traditional capacitors, supercapacitors have the characteristics of reaching the Farad level with super large capacitance, higher energy, wider operating temperature range, and longer service life. The number of charging and discharging cycles can reach over 100000, and they can quickly charge and discharge without maintenance. Because of these excellent characteristics, supercapacitors have developed rapidly. More importantly, the development of supercapacitors is entirely a spontaneous market behavior, with no policy subsidies or forced promotion. According to QYResearch statistics, the global sales of supercapacitors reached 1.2 billion US dollars in 2021, and it is expected to reach 5.8 billion US dollars by 2028, with a CAGR of 24.3%. In the past few years, supercapacitors have grown rapidly in the Chinese market. According to Sullivan data, the market size of supercapacitors in China rapidly increased from 1.63 billion yuan to 12 billion yuan from 2012 to 2018. From 2016 to 2019, although the growth rate of the Chinese supercapacitor market slowed down, the growth rate was still at a relatively high level. In the future, with the growth of supercapacitor applications in downstream application fields such as power grid, rail transit, and consumer electronics, China's supercapacitor market will continue to maintain a high-speed growth trend. According to the prediction of China Academy of Commerce, the size of China's supercapacitor market is expected to exceed 30 billion yuan by 2026.
1.3 Sodium batteries: Significant cost advantage, prioritizing batteries and negative * hard carbon links
1.3.1. Sodium batteries have obvious cost advantages and are expected to replace lithium batteries
With the continuous infiltration of new energy storage, sodium ion batteries with abundant resources, low costs, high energy conversion efficiency, long cycle life, and low maintenance costs have attracted much attention. At the same time, the introduction of multiple industry policies has assisted the development of sodium batteries. Similar to the working principle of lithium-ion batteries, sodium ion batteries are rechargeable electrochemical sodium ion batteries that primarily rely on sodium ions moving between positive and negative ions, using sodium ion intercalation compounds as positive materials. The research on sodium ion batteries has made rapid progress in the past decade. In the Implementation Plan for the Development of New Energy Storage during the 14th Five Year Plan period in January 2022, sodium batteries were ranked first among various energy storage technologies.
Sodium ion batteries have a higher abundance and lower cost in the Earth's crust. According to the paper "From Basic Research to Engineering Exploration" published by Rong Xiaohui in March 2020, the raw material cost of lithium batteries is 0.43 yuan/Wh, and the raw material cost of sodium ion batteries is 0.29 yuan/Wh, which is 32.6% lower than the cost of lithium batteries.
Although the energy density and cycle life indicators of sodium battery cores are weaker than those of lithium batteries, their cost advantage still makes them highly economical in downstream application scenarios such as energy storage. According to the conclusion in the article "Energy Storage Technology and Economic Analysis of Sodium Ion Batteries" by Hu Yongsheng et al. in June 2022, taking lead batteries, lithium iron phosphate batteries, ternary lithium batteries, and sodium ion batteries as examples, a model is used to calculate the full life cycle electricity cost of various batteries in peak shaving application scenarios. When considering power loss, the upper limit of electricity cost of sodium batteries is higher than that of lead batteries, respectively Lithium iron phosphate batteries and ternary lithium batteries are 52.2%, 32.4%, and 54.3% lower.
1.3.2 Positive * Material
Due to the early commercialization of the domestic positive materials industry system, the competitive landscape still needs to be tracked, and related leading enterprises still have a first mover advantage. At present, all three major types of positive materials have enterprise layouts. From the current research and development situation, the possibility of layered oxides becoming the mainstream is high. Its structural stability and poor cycling performance are expected to be rapidly improved with large-scale experiments. Layered oxides are currently mature positive materials, and the preparation process has some similarities with ternary materials, including precursor and solid-phase synthesis technology.
1.3.3 Negative * Material
Due to the larger atomic radius of sodium ions compared to lithium ions, sodium ions cannot efficiently de intercalate at the graphite negative electrode material. Therefore, it is crucial to find suitable sodium storage negative electrode materials. The negative electrode materials for sodium ion batteries mainly include amorphous carbon, alloys, transition metal oxides, etc. Among them, alloys have higher capacity but poor cycling and rate performance; The capacity of transition metal oxides is low; Amorphous carbon has excellent reversible capacity and cycling performance, and is expected to be commercialized after cost control. Amorphous carbon materials are mainly divided into two types: hard carbon and soft carbon. Hard carbon materials have high capacity but high cost; Soft carbon materials have low capacity, but can use anthracite as a precursor, which has a cost-effectiveness advantage. Anthracite can reach 150-300Ah/yuan, which is higher in cost-effectiveness than other precursors.
The Institute of Physics of the Chinese Academy of Sciences uses anthracite as the precursor to obtain a carbon negative material with excellent sodium storage performance through simple crushing and one-step carbonization. The soft carbon material obtained from cracking anthracite still has a high degree of disorder below 1600 ° C, with a carbon production rate of up to 90%, a sodium storage capacity of 220mAh/g, excellent cycling stability, and better performance than soft carbon materials derived from asphalt. In addition, according to Xu Bin from Beijing University of Chemical Technology's "Structural Regulation of Hard Carbon Negative Materials for Sodium Ion Batteries", anthracite is oxidized with concentrated sulfuric acid to introduce more oxygen-containing functional groups on the surface of anthracite molecules, improve the cross-linking activity with sucrose, and construct a heterogeneous structure. Its electrochemical performance and capacity can reach 325mAH/g, with a first effect of 84.5%. In addition to Zhongke Haina, currently, the domestic enterprises that layout sodium ion battery negatives are mainly lithium battery negatives, and their technical route is basically hard carbon negatives.
1.3.4 Electrolyte
In addition to the positive and negative * of the battery, electrolyte is also an indispensable and important component in the battery. Due to the insulation between the positive and negative terminals of the battery, a current circuit cannot be formed without electrolyte. The electrolyte plays a role in ion conduction between the positive and negative terminals, enabling the battery to obtain high voltage and high energy density. At present, in addition to playing a role in ion conduction in the system, some scholars are also conducting research on using electrolytes to modify, supplement sodium, and improve battery interfaces. As mentioned earlier, as charge carriers, sodium ions have high chemical similarity with lithium ions, so the electrolyte solvent system of sodium ion batteries is also similar to that of lithium-ion batteries, with liquid electrolytes as the mainstream; In liquid electrolytes, although aqueous electrolytes have the advantages of low cost and environmental friendliness, their application is limited due to their limited electrochemical window under high energy density and high power density conditions; In contrast, organic electrolytes can enhance their electrochemical window by selecting different solvents and controlling the concentration of sodium salts. Currently, Natron Energy in the United States uses water-based electrolytes, while other representative sodium battery companies use organic electrolyte systems.
In terms of solute selection, sodium salts are mainly used, which are divided into inorganic sodium salts and organic sodium salts. Inorganic sodium salts