After repeated charging and discharging, the battery capacity will drop. Since the battery capacity is directly related to the cruising range and power performance of the electric vehicle, Nissan considers that the Leaf's battery capacity will be “discarded” when it is reduced to 70% of the factory, and a new power battery will be replaced. Lead-acid batteries are generally dismantled and recycled after they are scrapped. The Leaf's lithium battery, with a capacity of 24kWh at the factory, can be stored at 16.8kWh when it is reduced to 70%. Is it too wasteful to use such a battery directly for disassembly and recycling? Based on the principle of maximizing profits, Nissan hopes to make secondary use of these “discarded” batteries, and then dismantle and recycle them after secondary use. The first stage: secondary use The current hot trend is to use “discarded” lithium batteries to build storage systems (residential or remote areas) for solar power and wind power. Why do solar power and wind power require a power storage system? Because they have to look at God's face. With solar power, solar panels can output a lot of power when there is plenty of sunshine, but what about rain and night? Generally, such power that may fluctuate drastically is not directly connected to the power grid, but is first stored in the power storage system, and then the power storage system outputs stable power to the outside. Why not use a new lithium battery and use a "discarded" lithium battery to build a power storage system? The reason is simple and the cost is lower. Sumitomo Corporation has calculated that using a new lithium battery to store 1 kWh will cost hundreds of thousands of yen, and if you use a "discarded" battery, they are sure to reduce this value to around 20,000 yen in 2020. In fact, there are already a number of companies that are doing this kind of storage system, including 4R Energy, SHARP, NEC, etc. of Nissan and Sumitomo. At present, these companies have introduced power storage systems, some for power companies and some for families.