Power battery cascade utilization and energy storage market is sought after

The first wave of power batteries is coming. In the industry's view, power batteries are generally used in new energy vehicles for about 3-5 years. When the battery capacity drops to about 75 %, they will be eliminated. From this calculation, the first batch of new energy vehicle power batteries put into the market are basically at the critical point of elimination. Forecasts from the China Automotive Technology Research Center show that the total number of end-of-life power batteries in the country will reach 12-2 .2 million tons from 2018 to 2020, and by 2025 this figure will soar to 350,000 tons.

Retired power batteries still have a high energy value, and their echelon use has both environmental protection and economic value. "The echelon utilization of energy storage batteries has realized the full-life comprehensive application of batteries, maximizing their use value and economic benefits. "A number of people in the industry told reporters.

Companies are exploring the road

According to calculations by Wangzidong, director of the China North Vehicle Research Institute and the National 863 power battery Test Center, the cost of using a lithium ion battery system for echelon use is about 1,000 yuan per kilowatt-hour. If the cycle life exceeds 1,000 times, the cost is more than that of lead-acid batteries. "In fact, the cycle life will exceed 3,000 times, so the echelon utilization of power cells is very competitive. "

Faced with the huge space used by the ladder, the company has realized where the business opportunities are and actively explored the way. For example, Shanghai Xida New Energy has implemented power cell terraced energy storage projects in Shanghai, Jiangsu, Guangdong and Zhejiang.

"Now that the cost of using the energy storage system for lithium batteries has entered a new era of 1 yuan / Wh, user-side energy storage applications have commercial promotion value. In an interview with reporters, Lijianduo, general manager of Shanghai Xida New Energy, said: "In contrast, the cost of energy storage for new batteries, such as lead-carbon battery systems, is 1.3-1 .4 yuan/Wh, and lithium power systems are 2 yuan/Wh. It can be seen that the cost advantage of terracing energy storage is obvious. "

The echelon uses the business model that can be used for storage energy, and mobilizes the initiative of the enterprise to enter this field. In the interview, the reporter understands that at present many enterprises have set their sights on this.

"Lions is planning to use decommissioned power cells on electric vehicles for energy storage. "Lions Technology Shenzhen clean power general manager Wangyu revealed.

"We are exploring and storing terraced energy utilization projects. At present, there are more echelon storage energy for the user side in China. Through peak and valley difference arbitrage, there can be a good income space. The addition of terraced storage energy on new energy storage will also have a large application space. "Wangyu told reporters.

"We are also vigorously exploring the use of energy storage and making some technical reserves. The general manager of Haopeng Technology of Ganzhou City told reporters that "the ladder utilization market is a process of gradual cultivation. With the continuous increase in the number of end-of-life batteries of the same model, it is believed that 1-2 years later, the economy of the ladder storage energy will be better. Reflect. "

Mr Lijianduo further said that given that the number of decommissioned batteries will multiply in the future, "the cost of terraced energy utilization will drop to 0.8 yuan/Wh this year and to 0.7 yuan/Wh in 2019, when the investment return on the project will increase significantly." We have also been ahead of schedule, with new energy depots, power battery manufacturers to carry out cooperation. "

Addressing technical challenges

The power battery of the retired new energy vehicle, the use of terraced energy storage, is not a simple parallel transplant. It also needs to solve the problem of battery consistency and safety, as well as further technical issues.

In the opinion of Wangyu, the most critical issue in the use of energy storage is the detection link. Only when the working state of the retired core or module is correctly judged, can the ladder utilization be matched. To this end, Tianjin Lion New Energy has developed and established a comprehensive assessment system with a ladder utilization information system as the core to test retired batteries. "The system integrates three important links such as database, model and evaluation method, and material management, and can provide all-round support for the residual value, information tracing, and ladder utilization plan of retired batteries. "

Lijianduo believes that group distribution is the core point of echelon utilization. "The batteries of a car are connected in series, coupled with a storage energy converter, and the series is firmly done without parallel connection. With the addition of a monitoring unit, an energy storage system can be formed to maximize the consistency of the battery. "

Wangzidong pointed out that power cells can theoretically recover echelon use, but the problem lies in the product structure and production process design of power cells. Many companies use laser welding technology to connect batteries to improve the reliability of battery work. Or use bolt fastening method. Such a connection structure makes it difficult for power cell terraces to be used. The cost of using old cells to reassemble into batteries is too large, which hinders the terraced use of power cells. "It is therefore necessary to make bold innovations in the structural design and production process of power cell products, facilitate the disassembly and maintenance of batteries, and shorten the battery assembly time through automated assembly equipment. "He further suggested.

Security concerns remain.

There are also different voices in the industry on the use of energy storage. Opponents believe that because it is directly related to electricity, ladder utilization is to be safe and efficient, and there can be no safety hazards.

"We are also studying the use of terraces, but this piece is more complex, not as simple as it is imagined, and the quality of decommissioned batteries is different. It also needs to solve many problems such as safety, consistency, technology, and economy. "Wu Jiamang, vice president of the Sunshine Power Supply Division, admitted frankly.

According to Wu Jiamao, the storage battery Hedongli battery has different concerns in terms of technical performance, and the storage system Hedongli system faces different levels of system complexity. In particular, after long-term use, the battery consistency presents a non-linear decline. The use of echelons is more similar to false propositions, and a large number of screening tasks for different consistent batteries also make enterprises deterred from economic aspects.

"Ladder use is valuable, but there are also bottlenecks. There are many scenes of ladder utilization, which do not necessarily have to focus on power storage and large-scale energy storage, because these require high safety and reliability. In an interview with reporters, Chenbo, president of Nandu Power, said: "Our use of steps is mainly applied to communication base stations, UPS, and low-speed car power industries. This will be easier. "

"I have a conservative view on the many uncertainties associated with the use of retired battery steps in large-scale storage systems. However, it is more realistic to apply in a small system. If the ladder utilization and household storage energy are combined, the total market volume is not small, and it does not have to be placed on a storage system above the megawatt level. "Beijing Shuang Deng Hui Feng JuNeng Technology Co., Ltd.. General Manager Tangxisheng told reporters.

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