How much does it cost to invest in a lithium-ion battery? Dry room cost analysis

Due to the rapid development of the Electric Vehicle industry in China, there is a huge market demand for lithium-ion batteries. Many battery manufacturers have also expanded their production capacity. Some companies have also entered the lithium-ion battery industry through this shareholder's wind. As an insider, Xiaobian I know that the lithium-ion battery industry is not so beautiful.

The lithium-ion battery industry not only has huge investment in initial construction, but also needs to consume huge amounts of money in later operations. Today, Xiaobian will take you to understand the important part of the lithium-ion battery production line - the investment and operating costs of the drying room.

The working voltage of lithium-ion battery can be as high as 4.2V , so the electrolyte can only use organic system. The lithium salt used is usually lithium hexafluorophosphate, which makes the whole process of lithium ion battery sensitive to moisture. Therefore, the dry room is a lithium ion battery. Especially necessary for large-scale production of lithium-ion battery manufacturers.

In order to meet the demand for moisture control of lithium ion batteries, usually the moisture in the drying room needs to be controlled below 100 ppm ( volume fraction ) , and the entire air dehumidification and heating process requires a large amount of electricity, taking a 16,000 m3 drying room as an example, usually The power demand is around 400kW .

The drying room is usually designed as a sealed space, and the moisture content of the intake air is usually controlled at about 15 ppm . The flow rate of the dry air is generally controlled by the moisture sensor to ensure that the air humidity in the entire drying room is maintained below 100 ppm . This paper will establish a model for analyzing the proportion of dry room investment and operating costs in the cost of lithium-ion batteries.

The model is designed to produce 10,000 sets of electric vehicle power battery packs per year . The construction investment is repaid in 6 years, and the space in the drying room is designed to be 16,000 cubic meters.

The gas used at the front end of the drying room is 33 ° C, the relative humidity is 50% or 2.5 vol% of air. First, this part of the air is cooled to 9 ° C to remove the moisture, and then this part of the drying gas will be discharged from the drying room. The gas is mixed, the temperature of the mixed gas is 24 ° C, the humidity is 0.07 vol% , the mixed gas is cooled again to 10 ° C, and then most of the mixed gas (95%) is sent back to the drying chamber, a small Part (5%) will be left as the cleaning gas stream and finally leave the system. The humidity inside the drying room is controlled at around 15ppm and the temperature is controlled at 25 °C. Low cleaning flow (5%) is an advantage of this system**, which can significantly reduce gas cooling and heating energy consumption.

The moisture in the drying room mainly comes from the human body, the moisture contained in the negative electrode, the gas brought in by the air shower door switch, etc., and the gas flow rate needs to be designed accordingly to ensure that the humidity of the gas flowing out of the drying chamber is controlled to 100 ppm or lower. In order to achieve the above requirements, the gas flow rate is controlled at 20 m3/s , and the residence time of the dry gas in the drying chamber is 13.6 min .

It is expected that the heat output in the drying room is 250 kW , so it is necessary to ensure that the temperature of the incoming drying gas is 14 ° C, thereby ensuring that the gas temperature in the drying chamber is around 25 .

Then we will now simply calculate the power consumption required in the operation of the drying room. The main refrigeration unit of the drying unit has a power of 426 kW , plus the front-end pre-cooling total cooling power is 483 kW , assuming a power factor of 3.5. The total cooling power is 138 kW and the total power of the fan is 167 kW . Therefore , the total power of the cooling and fan is 305 kW . The heating power is mainly concentrated on the back end of the heating of 63 kW and the dehumidification wheel of the regenerative heating power of 30 kW . Therefore, the total operating power of the drying unit is 398kW .

If the cooling and fan power are considered to be supplied by natural gas, and the efficiency of the natural gas is 0.4 , the total power of the drying unit becomes 856 kW .

The basic cost of such a drying room includes equipment costs of $ 74,1000 , annual electricity and gas costs of approximately $ 150,000 , labor costs (for 14 people ) of approximately $ 78,000 , and utility costs of approximately $ 180,000 .

This is only the investment cost of the drying room. It does not include the equipment used for battery production in the drying room. Equipment such as winders, liquid injectors, and sealing machines need to invest huge amounts of money. Lithium-ion battery electrode homogenization, coating, rolling and slitting equipment are millions of millions, so the lithium-ion battery industry is not only a technology-intensive industry, but also a capital-intensive industry, investing in the lithium battery industry. Need a strong financial base and strong technical support.