Lithium discusses how to improve the energy density of power batteries and the three major characteristics of materials

At present, the energy density of domestic ternary power battery cells is 170-190Wh/kg, and the vehicle range is 150-200km, which is far lower than the 500-600km range of traditional fuel vehicles. At a time when supporting facilities such as charging piles are still imperfect, improving the range has become one of the main tasks in the development of electric vehicles.

From a professional perspective, there are three main ways to increase the range of electric vehicles:

One is to increase the battery capacity,

The second is to improve the battery energy density,

The third is to achieve lightweighting of the entire vehicle through structural optimization and other means.

According to the Ministry of Science and Technology's new energy vehicle pilot project and the plans of major domestic power battery companies, the energy density of domestic single power batteries will reach 200Wh/kg by 2020. In comparison, there is more room to increase the range of electric vehicles by increasing the energy density of batteries.

So what are the ways to increase battery energy density?

Power battery materials play a vital role in improving battery energy density. Clarifying the obvious characteristics of the domestic power battery material industry and making targeted R&D investments and improvements will help improve the manufacturing level of material companies.

At present, domestic power battery materials mainly present the following three characteristics:

1. The localization rate has increased significantly

Currently, the localization rate of the four key materials used in power batteries exceeds 80%, among which the localization rate of negative electrodes and electrolytes is as high as 98%, the localization rate of positive electrode materials exceeds 95%, and the localization rate of diaphragms exceeds 80%.

The localization rate has increased significantly mainly because:

1) The domestic power battery system was developed earlier, and the comprehensive performance requirements are relatively low. The level of domestic materials has been steadily improving in recent years, with rapid progress in consistency and batch stability, which can meet the needs of domestic battery companies;

2) 70% of the current power batteries in China are lithium iron phosphate batteries. China began to develop and produce lithium iron phosphate batteries in 2004, and its supporting lithium iron phosphate materials and graphite negative electrode materials are relatively mature; 3) The current prices of power battery materials are generally low, and the competitiveness of imported materials is not strong.

2. Supply and demand are out of balance, prices have risen sharply, and a wave of expansion has begun

From September 2014 to the first quarter of 2016, domestic power batteries developed rapidly, with a year-on-year growth of more than 200%. In 2015, China's power battery output value reached 38 billion yuan, a year-on-year increase of 262%. The substantial growth of power batteries was mainly affected by the country's increased policy support for the new energy vehicle industry.

The demand for new energy vehicles has increased significantly, while the supply of upstream materials and batteries has increased slowly, resulting in an imbalance between supply and demand. Since the second half of 2015, the prices of many upstream and midstream materials in China's lithium battery industry have increased significantly, such as lithium carbonate, lithium hexafluorophosphate, copper foil, lithium iron phosphate, and wet-process diaphragms.

With the substantial increase in material prices, material gross margins have also rebounded significantly, attracting many companies to actively expand production and new entrants. From January to September 2016, the investment in the four major materials in China exceeded 35 billion yuan, among which cathode materials (including upstream mineral resources) and separators became investment hotspots.

3. The manufacturing levels of various materials vary greatly, and the industrialization of high-performance materials is progressing slowly.

China has become the world's largest producer and consumer of power batteries, but there is still a gap between domestic power batteries and those of Japan and South Korea, mainly in terms of energy density, product consistency, product stability, failure rate, etc.

For example, Tesla's main supplier Panasonic has been stably mass-producing 18650 power cells, with a single capacity of 3.1Ah, while the capacity of a single 18650 cell in China is mainly 2.2Ah and 2.4Ah, and only a few can reach 2.6Ah. This is closely related to the mismatch of various types of materials in China and the low level of automation of battery equipment. Domestic cathode material manufacturers can mass-produce power-type NCM622, but due to factors such as the immaturity of high-nickel electrolytes and the low manufacturing level of battery cell factories, NCM622 cannot be used in large quantities at present.

When will this wave of material price increases end? With low entry barriers, companies are expanding production and building production lines. Will there be overcapacity in the material field in 2017? Foreign-funded material companies have made strategic adjustments to the Chinese power battery market. Can they regain market share? Will Chinese material companies focus on going global or focusing on the domestic market? With high investment, what new opportunities are there in the lithium battery material field?