Electrochemical energy storage is currently mainly used in industrial applications in the form of lead batteries, lithium batteries, flow batteries, and sodium sulfur batteries.

Lead acid batteries are currently the most mature energy storage batteries, with advantages such as low cost and mature technology. At the same time, they are also constrained by shortcomings such as short lifespan and environmental friendliness.

Liquid flow batteries have a long lifespan and can be deeply charged and discharged, but their low power density and large volume require a large number of auxiliary equipment such as pipelines, valves, and circulation pumps during operation, which also makes their costs high. Sodium sulfur batteries have a high energy density, but their cost is high, and operational safety issues still need improvement.

Lithium batteries have high energy density, long lifespan, small size, and lower technical barriers and applicable conditions compared to liquid flow batteries and sodium sulfur batteries, making them a significant proportion of newly added energy storage capacity in recent years. However, the high cost remains a major obstacle to its widespread replacement of lead-acid batteries.

Although sodium sulfur batteries have the advantages of high specific power and specific energy, their operating temperature needs to be maintained at 300-350 degrees Celsius. The safety issues of battery insulation and large-scale operation also need to be studied.

At present, energy storage batteries are mainly used for auxiliary services in the power grid (peak shaving and frequency regulation), centralized clean energy grid connection, and user side (mainly in conjunction with photovoltaic power generation applications). The cost varies in different situations. According to Lazard's statistical data, energy storage lithium batteries currently have more economic advantages in the development of auxiliary services, and the cost of application on the user side is relatively high.

Since 2015, the installed capacity of electrochemical energy storage in China has maintained an annual growth rate of over 10%, increasing year by year. According to CNESA statistics, among the newly added electrochemical energy storage capacity in China in 2017, the user side had the highest proportion of newly added capacity, at 59%; Among the newly added capacity, lithium batteries are mainly used for auxiliary services and centralized clean energy grid connection, while lead-acid batteries with lower energy costs are mainly concentrated on the user side, accounting for 77% of the newly installed capacity on the user side.

According to Lazard's statistical data and the development of electrochemical energy storage in China, it can be seen that the current application of lithium battery energy storage can have economic benefits first, which is in the application of centralized clean energy grid connection and auxiliary services. However, user side applications, which have high costs, still need to rely on policy support and the reduction of lithium battery production costs.