Tiered utilization refers to the process of continuing to use a product that has reached its original design life through other methods to restore its functions in full or in part, and this process belongs to the basic same level or downgraded application method.
In the field of power batteries, lithium battery recycling and cascade utilization refers to the process of using high-power lithium batteries, sorting them, and then using them at lower power levels until they are scrapped. China Tower, a well-known domestic company in the cascade utilization sector, estimated that by 2020, the cumulative amount of power batteries that could be used for cascade utilization was 61.86 GWh.
The secondary use and recycling of lithium batteries are mainly based on three aspects: environmental protection, resource conservation, and profitability.
Environmental protection: The positive electrode material of lithium batteries contains heavy metal elements such as nickel, cobalt, manganese and lithium, which can pollute the environment and water; the carbon materials and graphite in the negative electrode material can cause dust pollution; in addition, the electrolyte of lithium batteries contains toxic chemical components, which can also cause fluoride pollution.
Resource conservation: Lithium batteries contain a large number of metal elements, such as nickel and graphite, which are relatively abundant in my country, but metal elements such as cobalt are scarce in my country; China has a large absolute content of lithium, but mining is difficult, and it is generally distributed in mines with harsh conditions such as Tibet, Qinghai, and Sichuan; lithium in salt lakes has a high magnesium ion content, making lithium extraction very difficult.
Profitable: The secondary use and resource recycling of lithium batteries can still be commercialized because the automotive industry has shifted to electrification in recent years, increasing the demand for lithium batteries and causing the prices of upstream precious metal materials to be very high. The price of cobalt is 600,000 yuan/ton, nickel is 100,000 yuan/ton, lithium carbonate is 170,000 yuan/ton, and lithium metal is 900,000 yuan/ton.
Regarding whether power batteries will cause pollution, the answer is no. The market has this concern because past power batteries (lead-acid batteries) caused lead pollution. However, lithium batteries are fundamentally different from lead-acid batteries; both are chemical power sources, but their characteristics are completely different.
Heavy metals refer to metals with a density greater than 4.5 grams per cubic centimeter. Elements classified as heavy metals by this standard include copper, lead, zinc, tin, nickel, cobalt, antimony, mercury, cadmium, and bismuth, totaling ten. However, gold, silver, platinum, and zinc do not produce the aforementioned phenomena, meaning they are not toxic. The previously reported "gold ingestion" only caused internal bleeding from obstructions or cuts, not due to the material itself being toxic.
Commonly used ternary lithium batteries include three materials: nickel, cobalt, and manganese. Nickel and cobalt are both toxic, meaning that these metals cannot be discarded casually, otherwise they will inevitably damage the environment. However, these materials will not be discarded either, because they are all very valuable.
It's important to note that lithium iron phosphate batteries contain no heavy metals and have significant advantages in terms of lifespan and thermal stability. Therefore, lithium iron phosphate batteries have high reuse value and do not cause pollution.
