After entering the 21st century, many countries have begun to formulate medium - and long-term solar energy development plans, such as the National PV Plan of the United States, the Sunshine Plan of Japan, and the Power on Plan of China's western provinces and regions. Solar energy application technologies will gradually deepen from five fields, namely, monocrystalline silicon and advanced devices, thin film photovoltaic technology, PVMaT, photovoltaic modules, system performance and engineering, photovoltaic application and market development.

For this reason, the solar cell technology has also made considerable progress. One of them is the progress of silicon solar cells, which are divided into three types: monocrystalline silicon solar cells, polycrystalline silicon thin film solar cells and amorphous silicon thin film solar cells. At present, monocrystalline silicon solar cells are the most mature, but because of the high cost and price of monocrystalline silicon, they will gradually be replaced by polycrystalline silicon thin film solar cells, However, the most promising is amorphous silicon thin film solar cells; Second, nanocrystalline solar cells are gradually coming into people's view. With extremely low production cost and simple process, they can achieve stable performance. Their production cost is only 1/5 to 1/10 of that of silicon solar cells. Their life can reach more than 20 years.

With the emergence of power battery, new energy and clean energy are the trend of the times. Battery technology is developing towards new materials and clean energy, and has also made significant breakthroughs. However, there are few commercial applications. The main reason is that the promise of low cost and multi capacity cannot be fulfilled. Therefore, the current research on batteries for electric vehicles is still focused on lithium batteries, followed by lead acid batteries, nickel metal hydride batteries and sodium batteries, Japan and the United States rank the top two in the world in terms of the number of patent applications for batteries and their management systems for electric vehicles.

In particular, the close cooperation between Tesla and Panasonic has not deliberately changed the battery materials, that is, lithium batteries are still used. Only by improving efficiency and production, battery optimization can be carried out according to automobile demand, which shows that the close combination of manufacturing and engineering technology is an available way to promote the commercial application of battery technology. However, the progress of lithium batteries is limited, and the production costs are also very high. The use and recycling of lithium batteries will bring some environmental pollution. In addition, lithium mines are unevenly distributed around the world. If electric vehicles use lithium batteries, they will still be subject to the situation of lithium producing countries, which is the same as the current situation of fuel vehicles.

Therefore, according to insiders, in the future, batteries for electric vehicles still need to develop towards new materials and clean energy, such as solar energy, wind energy, hydropower, silicon materials, nanocrystals, etc., which is the best way to solve the high cost of batteries, environmental pollution and energy crisis once and for all.