What Should I Do with Old Batteries?

Waste battery recycling refers to recycling used batteries through recycling. The most used industrial battery in China is lead storage batteries, which account for more than 50% of the total cost of storage batteries. Pyrolysis, wet metallurgy and solid-phase electrolytic reduction technologies are mainly used. . The shell is made of plastic, which can be regenerated and basically achieves no secondary pollution.

Recycling of used batteries

Nickel-cadmium, nickel-hydrogen, and lithium-ion batteries are more commonly used in small secondary batteries. Cadmium in nickel-cadmium batteries is one of the heavy metal elements strictly controlled by the environment. Organic electrolytes in lithium-ion batteries, and nickel-cadmium and nickel-hydrogen batteries Alkali and heavy metals such as copper, which is an auxiliary material for battery production, pose pollution to the environment. Small secondary batteries currently use only a few hundred million in China, and most of them are small, ^[1-2]

(1) Zinc-manganese batteries The dangers of zinc-manganese dry batteries are mainly the hazards caused by the electrolyte solutions such as mercury, acids, and alkalis contained in them that may enter the environment after being discarded. Heavy metal mercury can cause central nervous system diseases and is the culprit of "Minamata disease" in Japan.

(2) Button batteries Button-type zinc-silver batteries are widely used in electronic clocks, calculators, hearing aids, etc., and are relatively familiar battery types. The hazards of such batteries are also mainly caused by mercury, cadmium and silver. According to relevant data, a button battery can pollute 600,000 liters of water.

(3) Lithium batteries. Lithium batteries refer to batteries that contain lithium (including metallic lithium, lithium alloys, lithium ions, and lithium polymers) in the electrochemical system. Including primary batteries and metal lithium and lithium ion secondary batteries. Because of its advantages such as high cost performance, long storage life and wide operating temperature range, it is used in watches, cameras, calculators, backup power supplies, pacemakers, safety alarms, etc. This type of battery is relatively harmless, and its recycling is mainly to recover the useful component metal lithium.

(4) Alkaline batteries Alkaline batteries include zinc-silver, cadmium-nickel, iron-nickel, and nickel-hydrogen batteries. Nickel cadmium battery is currently the most widely used battery series, and it is also a type of battery that has been the focus of environmental pollution. Cadmium is a very toxic substance and has carcinogenic properties. Nickel also has carcinogenic properties and is obvious to aquatic organisms. Harmfulness. According to the US EPA survey, cadmium in waste cadmium nickel batteries accounts for 75% of total cadmium in municipal solid waste.

(5) Lead-acid battery Lead-acid battery is currently the world's largest and most widely used battery. Sales account for more than 30% of global battery sales. China's annual output of lead-acid batteries is nearly 30 million kWh. The pollution of this type of battery is mainly the pollution of heavy metal lead and electrolyte solution. Lead can cause neurasthenia of the nervous system, numbness of hands and feet, indigestion of the digestive system, blood poisoning and kidney damage.

Waste batteries are largely discarded in the environment. The acid and alkaline electrolyte solutions will affect the pH of the soil and water systems, making the soil and water systems acidic or alkaline. After heavy metals such as mercury and cadmium are absorbed by organisms, they enter through various channels. The human food chain gathers in the human body, causing the human body to be teratogenic or mutagenic, and even cause death. A button battery can pollute 600,000 liters of water, which is equivalent to a person's drinking water in a lifetime. A battery rots in the ground and can make a square meter of land useless. Of the five substances that pose the greatest threat to the natural environment, three are contained in the battery.

Waste battery pollution

Civil dry batteries are currently the most widely used and most decentralized battery products, with an annual domestic consumption of 8 billion. There are mainly two series of zinc-manganese and alkaline zinc-manganese, as well as a small amount of zinc-silver and lithium batteries. Zinc manganese battery,

The lead battery industry due to the "blood lead pollution incident" caused by the country to step up measures to control heavy metal pollution and eliminate outdated production capacity, leading to the use of the lead industry shock, lead prices fell, the lead battery industry as the main body of the battery industry affected by this slowed growth , Which affects the entire industry into a period of sluggish development.

The cause of the "blood lead pollution incident" is that on the one hand, some enterprises in the lead industry have long neglected pollution control and eliminated backward production capacity, resulting in lead pollutants generated during the production process flowing into the atmosphere, water, and soil without treatment, causing serious lead pollution; On the other hand, a large number of waste lead-acid batteries lack a more complete environmentally friendly and pollution-free treatment method, which is extremely likely to cause leakage of lead acid during the treatment process, causing serious environmental pollution.

Now, the advent of a new pollution-free lead-acid battery technology for vehicles is likely to change this situation. This pollution-free lead-acid battery technology for vehicles, recently developed by Polish scientists, uses a combination of hydrometallurgy and pyrometallurgy to process sulfuric acid in lead-acid batteries into laundry powder raw materials. During use, the lead metal and the battery paste can be melted in a rotating furnace and converted into powder. The polyethylene grid of the lead battery case and the polypropylene case can be processed into particles for secondary use. It will not cause secondary pollution during the entire production process. This technology not only greatly reduces environmental pollution, but also turns waste into treasure. Its products provide important raw materials for other industries and truly achieve "two birds with one stone." The technology has won a gold medal at the Brussels 2011 Innovation Research and New Technology Exhibition. This technology is being used in Poland. ^[3]

The process of recycling used batteries ^[4] is roughly as follows:
1. Classification: You can smash the recovered used batteries, peel off the zinc case and battery bottom iron, and remove the copper cap and graphite rod. For the remaining black objects, it is a mixture of manganese dioxide and ammonium chloride as the battery core. After the above substances are collected and processed separately, we can get some useful substances. The ink sticks can be used as electrodes after being washed and dried.
2. Zinc granulation: Wash the peeled zinc shell and place it in a cast iron pot. After heating, keep it for 2 hours, remove the layer of scum above, pour it out for cooling, and then drip it on the iron plate. After waiting until solidification, zinc particles can be obtained.
3. Recycling the copper sheet: We can flatten the copper cap and then wash it with hot water, then add a certain amount of 10% sulfuric acid and boil it for 30 minutes to remove the surface oxide layer, remove it, wash it, and dry it. Copper sheets can be obtained.
4. Recovery of ammonium chloride: We put the black substance in the tank, and then add 60oC warm water and stir for one hour. This will make the ammonium chloride completely dissolve in water, stand, filter, and wash the filter residue twice to collect the mother liquor. .
5. Recovery of manganese dioxide: We wash the filtered residue three times with water, filter, put the filter cake in a pot and evaporate to remove a little carbon and other organic matter, and then put it into the water and stir it for 30 minutes. Dry the filtered cake at 100-110oC so that we can get manganese dioxide.