The peak-to-valley adjustment of electricity consumption is a difficult problem. Usually, more power plants need to be built to ensure peak electricity consumption. In this way, when the electricity consumption is low, the generator still needs to run, which not only causes the burden of increasing investment, but also causes energy waste. In recent years, some foreign companies have changed their thinking and purchased medium and large-scale energy storage equipment with funds used to invest in power plants, charging them when electricity consumption is low, and using the electricity stored in equipment during peak hours to charge by time, forming a win-win situation. Figure 1 is an example of a lithium-ion battery as an energy storage device.In the past, lead-acid batteries were mostly used in energy storage devices. First, the price of lead-acid batteries was relatively low, and second, lead-acid batteries could be float-charged. Li-ion batteries used to be unsatisfactory in terms of shelf life and float charging. In recent years, due to the maturity of LiNixCo1-x-yMyO2 and the emergence of LiFePO4, these problems will be gradually solved.

Figure 1 Example of lithium-ion battery used in energy storage device

The French SAFT company reported that its G3 battery (the positive electrode is LiNi0.75Co0.2Al0.05O2) has been floated for more than 1400 days, and the capacity and internal resistance have changed very little. The test results are shown in Figure 2.

Figure 2 G3 Li-ion battery float test results
1-3.8V, 40℃; 2-3.8V, 60℃;
3-3.9V, 40℃; 4-3.9V, 60℃

Energy storage devices are also widely used in other fields, that is, combined with solar energy and wind energy to form an "all-green" new energy system. Energy is an important aspect of today's economic construction and social development. How to adjust the burden when energy supply is tight and sufficient has always been a topic of research in various countries. The use of solar energy and wind energy is one of the ways. At present, many places and troops have been equipped with solar and wind power generation devices. For example, the Xinjiang Military Region has installed solar and wind power generation devices for its 68 border defense companies, which has ended the "five difficulties" (difficulty in using electricity, bathing, drafting, heating, etc.). hardships and housing difficulties). A considerable number of troops stationed on the island have also installed such power generation devices, but because most of the batteries of these devices currently use lead-acid batteries, they still have a great impact on the local environment and ecology. Usually, the ecological environment of these outposts is harsh and fragile, and the degradation ability of harmful substances is low. Once damaged, it is difficult to restore, and it will also cause long-term physical and mental damage to the officers and soldiers stationed there. Lithium-ion batteries are green batteries since their introduction in the early 1990s, and are considered to be ideal for high-capacity and high-power batteries because of their high energy density, good cycle performance, and high charge retention performance. Lithium iron phosphate and ternary Li-Ni-Mn-Co-O cathode materials show good performance as key materials for ideal energy storage and storage systems. Lithium iron phosphate has the characteristics of low price, non-toxic and non-polluting, and good safety; the layered ternary Li-Ni-Mn-Co-O cathode material has high capacity (above 140mA·h/g), thermal stability, chemical It has the advantages of stability, high current discharge performance and good safety. Therefore, lithium-ion batteries have good application prospects in power batteries. Using it to replace lead-acid batteries will greatly benefit the environment.

Green energy lithium ion battery