Here is the energy storage knowledge you want to know (IV) Technical points involved in energy storage technology

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Here is the energy storage knowledge you want to know (IV) Technical points involved in energy storage technology [Copy link]

The technical points involved in energy storage technology mainly include the following aspects:

Physical energy storage technology: storing energy in physical form, including pumped storage, compressed air storage, etc.

Electrochemical energy storage technology: using chemical reactions to convert electrical energy into chemical energy and then storing it, including lithium-ion batteries, lead-acid batteries, sodium-sulfur batteries, etc.

Thermal energy storage technology: uses the principles of heat conduction and phase change to convert energy into thermal energy storage, including thermal storage solar thermal power generation, salt water thermal energy storage, etc.

Mechanical energy storage technology: using mechanical principles to convert kinetic energy or potential energy into storable energy forms, including flywheel energy storage technology, spring energy storage technology, etc.

Superconducting energy storage technology: using the characteristics of superconductors to achieve high-density energy storage, including superconducting energy storage devices, superconducting magnetic energy storage devices, etc.

It should be noted that different types of energy storage technologies differ in terms of energy density, reliability, efficiency, etc., and technologies that suit specific needs should be selected. In addition, the application of energy storage technology not only in the energy field, but also involves many other fields, such as electric vehicles, aerospace, mobile communications, smart homes, etc.

Electrochemical energy storage Electrochemical energy storage is to complete the mutual conversion between electrical energy and chemical energy through electrochemical reactions, thereby realizing the storage and release of electrical energy. At present, the main energy storage batteries used mainly include lead-acid batteries, flow batteries and lithium-ion batteries. In the future, sodium-ion batteries will also be gradually used in energy storage as the industrial chain matures.

1. Lead-acid battery
Lead-acid battery is a secondary battery with lead dioxide as the positive electrode, metallic lead as the negative electrode, and sulfuric acid solution as the electrolyte. It has a history of more than 150 years and is the earliest secondary battery used on a large scale.
Lead-acid batteries have low energy storage costs, good reliability, and high efficiency. They are widely used in UPS and are also the dominant technical route for large-scale electrochemical energy storage in China in the early days. However, due to the short cycle life, low energy density, narrow operating temperature range, slow charging speed, and the large impact of lead metal on the environment, the future application of lead-acid batteries will be greatly limited.

2. Liquid flow battery

The technical paths of liquid flow battery include all-vanadium liquid flow battery, iron-chromium liquid flow battery, zinc-bromine liquid flow battery, etc. Among them, all-vanadium liquid flow battery has the best comprehensive performance and the highest degree of commercialization. The

positive and negative electrolyte storage tanks of liquid flow battery are separated and placed outside the stack. The positive and negative electrolytes are pumped into the liquid flow battery stack through pipes through two circulating power pumps and electrochemical reactions continue to occur. The storage and release of electrical energy are completed by converting chemical energy into electrical energy. The power of liquid flow battery depends on the size of the electrode reaction area, and the storage capacity depends on the volume and concentration of the electrolyte. Therefore, the scale design of liquid flow battery is more flexible and changeable.

We believe that in terms of long-term energy storage, all-vanadium liquid flow battery will have cost advantages and differentiated competitive advantages over other technical paths such as lithium batteries.
3. Lithium-ion battery
Lithium-ion battery realizes energy storage by embedding and de-embedding lithium ions in positive and negative electrode materials. Lithium-ion battery has high energy density and long life, so it is gradually becoming the mainstream route of electrochemical energy storage. According to the different positive electrode materials, lithium-ion batteries are divided into lithium cobalt oxide, lithium manganese oxide, lithium iron phosphate and ternary batteries.
Lithium iron phosphate batteries have significant comprehensive advantages in the field of energy storage. They have moderate energy density, better safety and service life than other battery types, and lower cost. Due to the scarcity of metal cobalt, the price of lithium cobalt oxide batteries is much higher than other batteries, and the cycle life and safety are poor, so they are almost not used in the field of energy storage. The energy density of lithium manganese oxide batteries is similar to that of lithium iron phosphate batteries. Although the price is lower than that of lithium iron phosphate, the low service life leads to a higher cost per kilowatt-hour in the whole life cycle than that of lithium iron phosphate batteries, so they are less used. The energy density of ternary batteries is much higher than that of other battery types, and the service life can also reach 8-10 years, but the safety is relatively poor and the cost is much higher than that of lithium iron phosphate batteries. Therefore, in the field of energy storage that does not require extremely high energy density, the application prospect is weaker than that of lithium iron phosphate batteries.
4. Sodium ion battery
The working principle of sodium ion battery is similar to that of lithium ion battery, and the charging and discharging are realized by the insertion and extraction process of sodium ions between the positive and negative electrodes. Compared with lithium iron phosphate batteries, sodium ion batteries have higher safety performance, low temperature performance, and fast charging performance, and lower cost. In addition, sodium resources are far more abundant than lithium resources and are distributed all over the world. If sodium ions can be widely used, China will largely get rid of the current situation of limited lithium resources.
The disadvantages of sodium ion batteries are mainly reflected in the low number of cycles and the immaturity of the industrial chain. At present, the cycle life of sodium batteries is generally 2000-3000 times. The immaturity of the industrial chain leads to higher upstream prices, and the cost advantage of sodium batteries cannot be shown.

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It's a very good introduction. Take a good look and learn from it. It will be useful in the future.