At present, the anode of lithium battery is usually copper foil with thickness of less than 8 μm. Electrolytic copper foil can be divided into electronic circuit copper foil for Printed Circuit Board and Lithium Battery Copper Foil for Lithium batteries according to the application field and according to the thickness of copper foil, according to the standard, it can be divided into ultra-thin copper foil (≤6μm) , ultra-thin copper foil (6 ~ 12μm) , thin copper foil (12 ~ 18μm) , conventional copper foil (18 ~ 70μm) and thick copper foil (> 70μm) . At present, copper foil for lithium-ion battery is usually used below 8μm, and copper foil for electronic circuit is usually thicker than copper foil for lithium-ion battery, mostly in the range of 12μm ~ 70μm.

Compared with 8 μm lithium copper foil, the energy density of 6 μm and 4.5 μm lithium copper foil can be increased by 5% and 9% . According to the formula of energy density of lithium battery: Mass Energy Density = battery capacity/battery mass, the battery mass can be reduced by the constant battery capacity, or increasing the capacity of a battery while keeping its quality constant to increase its energy density. The June 2019 data of the electric vehicle observer shows that the average energy density of the single cell of the new energy vehicle power battery is 228.8 wh/kg. If the 8 μm copper foil commonly used in the current new energy vehicle battery is replaced by 6 μm or 4.5 μm copper foil, the copper foil required per unit energy can be reduced to 0.62 kg/kWh (6μm copper foil) or 0.47 kg/kWh (4.5 μm copper foil) , respectively, further calculation shows that the new energy density of the reduced copper foil is 240.2 wh/kg (6μm copper foil) and 249.6 wh/kg (4.5 μm copper foil) , respectively, compared with the lithium battery using 8μm copper foil, the energy density of the battery was increased by 5% (6μm copper foil) and 9.1% (4.5 μm copper foil) , respectively.

1. Global Lithium battery production will maintain a relatively high growth rate, with China’s total lithium battery shipments reaching 306.52021, up 114% year-on-year, in the power battery sector to expand to 72% . 2021 so far, the domestic new energy vehicle market has shown explosive growth trend, the growth of digital products market is stable, lithium battery energy storage widely used. According to GGII statistics, China’s power battery shipments are 220 GWH, up 175 percent year on year, with terminals accounting for 72 percent of the total, up from 56 percent in 2020, and 37 gwh for storage batteries and 10 Gwh for small power batteries, according to 2021, 12% and 3% respectively. In recent years, China’s 3C digital battery shipments growth rate is relatively stable, 20213C digital battery shipments are estimated to be about 39.5 gwh, accounting for 13% .

The institute predicts that Global Lithium battery shipments will grow at a compound annual rate of 37.8% from 2020 to 2025. Since 2020, global lithium battery shipments have increased 306 gwh, up 34.8 percent year-on-year, driven by the growth of the global new energy vehicle market, especially the explosion of the European market. Among them, the annual shipments of power batteries are 186GWh, making it the world’s largest consumer of lithium batteries, with terminal consumption accounting for 60.8% , and the shipments of digital lithium batteries are 77GWh, electric Tools, electronic toll collection systems (ETC) , mobile robots (AGV) , wearable devices and other applications are driving the rapid rise of li-ion batteries and small power batteries, the annual shipments are 27GWh and 16GWh, respectively. The 2021 predicts that the global lithium battery market will continue to grow at a medium to high speed in the next few years, with global lithium battery shipments expected to reach 1523GWh by 2025, a compound annual growth rate of 37.8% in 2020 -- 2025.

Lithium battery application scenarios are divided into three application areas: power, 3C digital and energy storage. In 2020, global sales of new energy vehicles reached 3.15 million units, up 42.5 percent year on year. It is estimated that the installed rates of 20232021 are 290GWh, 475GWh and 655GWh, respectively, and the growth rates are 113.0% , 63.8% and 37.7% . The installed capacity of digital consumption battery in 2023 is expected to be 90 Gwh, 95 GWH and 100 GWH, respectively, with year on year growth rates of 5.9% , 5.6% and 5.3% . It is estimated that the installed capacity of other batteries in 2023 will be 94 Gwh, 139 gwh and 187 gwh respectively, and the growth rate will be 81% , 48% and 34% respectively. To sum up, it is estimated that the electricity demand in 2023 will reach 474.35 Gwh, 709.55 Gwh and 941.5 Gwh, respectively, with an annual compound growth rate of 51% .

The author expects that the installed output ratio of lithium battery will remain low in the next two years, and the global output of lithium battery will maintain high growth rate. According to the statistics of Wind, the quantity of power battery in China in 20212019 ~ 2021 only accounts for about 71% , 78% and 70% of the annual output. The gap between the output and installed capacity is caused by the inventory cycle of battery and downstream industry, installed capacity is expected to remain low for the next two years, given the massive expansion plans of cathode material and battery manufacturers since the end of 2021.

2. The demand of extreme energy density (ECD) promotes the development of ultra-thin lithium copper foil in the direction of high energy density. Ningde Times, byd and other power lithium-ion battery companies 6μm lithium-ion copper foil has been mature and fast switching, other power lithium-ion battery companies are also accelerating the application of 6μm lithium-ion copper foil, ultra-thin lithium copper foil products have gradually been applied in key enterprises. In 2020, the permeability of ultra thin lithium copper foil was 50.4 percent, according to the 2021; in the first half of the year, the permeability was 55.6 percent. Under the requirement of high energy density and low cost, 4.5 μm lithium copper foil is expected to become one of the mainstream products after 6μm lithium copper foil. In the first half of the year, Ningde’s 2021 used between 600 and 700 tonnes of copper foil for 4.5 μm Lithium Ion batteries, according to Gaogong.

Because of the accelerated iteration of lithium copper foil products, the application prospect of copper foil for 4.5 μm lithium battery is broad. Downstream applications are required to upgrade the upstream copper foil technology to drive iterative acceleration. Before this, the lithium copper foil had a long period from 12μm to 8μm. In a few years, our country has upgraded from 7μm ~ 8ΜM copper foil to 6μm copper foil for lithium battery, and thin copper foil of 5μm, 4.5 μm and 4μm has been produced. As the industrialization technology of 4.5 μm copper foil matures and the application technology of battery enterprises improves gradually, the application of 4.5 μm copper foil for lithium battery will increase gradually. The technology strength of copper foil for lithium battery in our country is in the leading level in the world, but overseas battery manufacturers have not used 6μm copper foil for lithium battery on a large scale. 

Source: Oriental Securities, by Liu Yang