Can the time of lead ion enrichment by electrodeposition be extended to 300 seconds? why

What is a battery? Battery is an energy conversion and storage device, which mainly converts chemical energy or physical energy into electrical energy through chemical reaction. Battery is a kind of chemical power supply, which consists of two electrochemically active electrodes with different compositions. The two electrodes are immersed in an electrolyte that can provide medium conduction. When connected to an external carrier, they can provide electrical energy by converting internal chemical energy. Primary battery and secondary battery A primary battery, also known as a non-rechargeable battery or a primary battery, generates electric energy through a one-way chemical reaction of the battery. The discharge of the primary battery leads to permanent and irreversible changes in the chemical composition of the battery. But rechargeable batteries, also called secondary batteries, can be discharged in applications or charged by chargers. Therefore, the secondary battery stores energy instead of generating energy. What parts does the battery consist of? Any kind of battery is composed of four basic components, and these four main components are two electrodes, electrolyte, diaphragm and casing made of different materials. How many kinds of batteries are there? Chemical batteries can be divided into: primary batteries (primary batteries); Secondary battery (rechargeable battery) lead-acid battery. Among them, primary batteries can be divided into paste zinc-manganese batteries, cardboard zinc-manganese batteries, alkaline zinc-manganese batteries, button zinc-silver batteries, button lithium-manganese batteries, button zinc-manganese batteries, zinc-air batteries and primary lithium-manganese batteries. Secondary batteries can be divided into: nickel-cadmium batteries, nickel-hydrogen batteries, lithium-ion batteries, secondary alkaline zinc-manganese batteries and so on. Lead-acid batteries can be divided into open lead-acid batteries and fully enclosed lead-acid batteries. What is a zinc-manganese dry battery? Zinc-manganese battery, also called Leclant battery, was invented by French scientist Leclant in 1868. Zinc (Zn) is used as negative electrode, manganese dioxide (MnO2) is used as positive electrode, and neutral ammonium chloride (NH4C 1) and zinc oxide (ZnC 12) are used as electrolyte solution. According to the purpose of the isolation layer, it can be divided into paste battery and plate battery, and plate battery can be divided into ammonium battery and zinc battery according to the different electrolyte. What is an alkaline zinc-manganese battery? It was developed on the basis of zinc-manganese battery in the middle of 20th century, and it is an improved version of zinc-manganese battery. The battery uses the aqueous solution of potassium hydroxide (KOH) or sodium hydroxide (NaOH) as the electrolyte solution, and adopts the negative electrode structure opposite to that of the zinc-manganese battery. The negative electrode is a paste-like colloid, the copper nail is used as a current collector, the positive electrode is outside, the active substance and the conductive substance are pressed into a ring to be connected with the battery case, and the positive and negative electrodes are separated by a special diaphragm. What is a lead-acid battery? 1859, discovered in Plante, consists of five basic parts: positive plate, negative plate, electrolyte, separator and container (battery tank). The battery is made of lead dioxide as positive active material, lead as negative active material, sulfuric acid as electrolyte, microporous rubber, sintered PVC, glass fiber and polypropylene as diaphragm. What are nickel-cadmium batteries and metal hydride batteries? Both of them use nickel oxide or nickel hydroxide as the positive electrode, potassium hydroxide or sodium hydroxide as the electrolyte solution, and metal cadmium or metal hydride as the negative electrode. Metal hydride battery was invented by using the electrochemical reversibility and hydrogen release reaction of hydrogen-absorbing alloy in the late 1980s, and it is the leading product of small secondary battery. What is a lithium battery? Refers to the battery with lithium metal or lithium compound as active substance, which is called lithium battery and can be divided into primary lithium battery and secondary lithium battery. What is a lithium-ion battery? It refers to a battery made of carbon materials capable of intercalating and deintercalating lithium ions instead of pure lithium as the negative electrode, lithium compounds as the positive electrode and mixed electrolyte as the electrolyte. What is a fuel cell? Refers to a device that uses fuel (such as hydrogen or hydrogen-containing fuel) and oxidant (such as pure oxygen or oxygen in the air) to directly connect to generate electricity. It has the characteristics of high efficiency, electrochemical reaction conversion efficiency of over 40% and no pollution gas emission. Acid zinc-manganese dry battery Zinc-manganese battery, also called Leclanche battery, was invented by French scientist Leclanche in 1868, with zinc (Zn) as the negative electrode, manganese dioxide (MnO2) as the positive electrode and neutral ammonium chloride (NH4C 1) and zinc oxide (ZnC65438) as the electrolyte. A battery with starch or pulp paper as the isolation layer is called a zinc-manganese battery. Because its electrolyte solution is usually made into gel or adsorbed on other carriers, it is also called zinc-manganese dry cell. According to the purpose of the isolation layer, it can be divided into paste battery and plate battery, and plate battery can be divided into ammonium battery and zinc battery according to the different electrolyte. Acid zinc-manganese dry battery uses zinc tube as negative electrode. After amalgam treatment, the surface properties are more uniform, so as to reduce zinc corrosion and improve the storage performance of the battery. The cathode material is a mixed slurry composed of manganese dioxide powder, ammonium chloride and carbon black. The carbon rod is inserted into the middle of the cathode material as a conductor for extracting current. There is a layer of reinforced separation paper between the positive electrode and the negative electrode, which is soaked with electrolyte solution containing ammonium chloride and zinc chloride, and the upper part of zinc metal is sealed. This battery was invented by Lackland in the 65438+60s, so it is also called Lackland battery or carbon-zinc dry battery, which can be expressed as: (-) Zn | NH4Cl (20%) ZnCl2 | MnO2, C (+)? Although this battery has a long history, its electrochemical process is not fully understood. Generally speaking, the reaction in the battery is as follows: the positive electrode is the cathode, manganese is reduced from tetravalent to trivalent 2mno2+2h2o+2e-→ 2mno2 (OH)+2oh-the negative electrode is the anode, and zinc is oxidized to divalent zinc ion: Zn+2 NH 4 cl-→Zn(NH3)2c L2+2h+2e- The total reaction of the battery is 2mno2+Zn+2nh4cl. The practical experience shows that the volt-ampere characteristics of the battery are related to the source of manganese dioxide and directly depend on the oxidation valence state of manganese. At present, NH4Cl has been completely replaced by ZnCl2 electrolyte, which fully shows that Zn2+ and Cl- coordinate [ZnCl 2]2- without NH4+. Before discharge, pH=5, and after discharge, pH is neutral when it rises to pH = 7. The characteristics of the battery are: (1) the open circuit voltage is1.55v ~1.70v; (2) abundant raw materials and low price; (3) Various models 1 No.5; (4) It is convenient to carry and suitable for intermittent discharge. Disadvantages are: the voltage drops continuously during use, which can not provide stable voltage, low discharge power, small specific energy, poor low temperature performance, and can not work at -20℃. Only alkaline zinc-manganese dry batteries can be used in cold areas. Alkaline zinc-manganese dry battery Alkaline zinc-manganese dry battery is an improved zinc-manganese battery developed on the basis of zinc-manganese battery in the middle of the 20th century. The battery uses the aqueous solution of potassium hydroxide (KOH) or sodium hydroxide (NaOH) as electrolyte solution, and adopts a negative electrode structure different from that of zinc-manganese battery. The negative electrode is changed from zinc sheet to zinc powder, the shell is changed to steel skin, and the positive electrode is still graphite and manganese dioxide. /kloc-0 was successfully developed in/882, 19 12 and put into production in 1949. It was found that when KOH electrolyte solution was used instead of NH4Cl as electrolyte, the electrolyte and structure changed greatly, and the specific energy and discharge current of the battery increased significantly. Negative electrode: Zn+2OH-=ZnO+H2O+2e- Positive electrode: 2MnO2+2H2O+2e-=2MnO(OH)+2OH- The total reaction is: Zn+2MnO2+H2O=ZnO+2MnO(OH) Advantages of alkaline zinc-manganese dry battery, the electrolyte changes from neutral to alkaline, the ionic conductivity is better, and so is the negative electrode. According to the test, the capacity and discharge time of this battery are several times higher than those of ordinary zinc-manganese dry batteries. The superior performance makes this kind of battery develop rapidly. At present, China mainly produces acidic zinc-manganese batteries and alkaline zinc-manganese batteries. The former is Dagong, Peony, China, Swan and 555, while the latter is Fu Nan, Twin Deer and White Elephant. According to 1995 statistics, the global total output of dry batteries is 25 billion, including 7 billion alkaline manganese batteries. In recent five years, the annual growth rate of alkaline manganese batteries in the United States, Europe and Japan has exceeded 12%, and the domestic market share of alkaline manganese batteries in the United States, Europe and Japan is 72%, 52% and 29% respectively. The total output of alkaline manganese batteries in China is nearly 300 million, accounting for only 3% of the total output of dry batteries, and it is expected to increase to 10% ~ 15% in five years. Judging from the current development situation, brands such as Fu Nan, Shuanglu and Baixiang have reached international standards, with the highest production speed reaching 200 /min and the United States and Japan reaching more than 300/min. Nickel-cadmium battery Nickel-cadmium battery uses Ni(OH)2 as the positive electrode, CdO as the negative electrode, and alkaline solution (mainly KOH) as the electrolyte. When the Ni-Cd battery is charged, the following reactions occur at the anode: Ni (OH) 2–E+OH-→ NIOOH+H2O; At the cathode: Cd(OH)2+2e→Cd+2OH- The total reaction is 2ni (OH) 2+CD (OH) 2 → 2niooh+CD+2h2o; When discharging, the reaction is reversed. With the increase of NiOOH concentration, the concentration of Ni(OH)2 decreased, and the positive potential gradually increased, while with the increase of Cd, the negative potential gradually decreased. When the battery is fully charged, the potentials of the positive electrode and the negative electrode both reach an equilibrium value, and the difference between the two potentials is the charging voltage of the battery. Ni-MH battery Ni-MH battery is a new type of green battery developed in 1990s. It has the characteristics of high energy, long life and no pollution, so it has become one of the high-tech products developed by all countries in the world. The birth of Ni-MH battery should be attributed to the discovery of hydrogen storage alloy. As early as the end of 1960s, people discovered a new functional material hydrogen storage alloy, which can absorb and release a large amount of hydrogen under certain temperature and pressure conditions, so it is vividly called "hydrogen absorption sponge". Some hydrogen storage alloys can be repeatedly charged and discharged in strong alkaline electrolyte solution and exist stably for a long time, thus providing us with a new negative electrode material, and on this basis, nickel-hydrogen batteries were invented. The hydrogen storage alloy in Ni-MH battery is actually an intermetallic compound. Intermetallic compounds have been widely used in the manufacture of nickel-hydrogen batteries, which are mainly divided into two categories. The most common is AB5, where A is a mixture of rare earth element (or) and titanium (Ti); B is nickel (Ni), cobalt (Co), manganese (Mn) and/or aluminum (Al). The electrodes of some high-capacity batteries are mainly composed of AB2, where A is titanium (Ti) or vanadium (V), B is zirconium (Zr) or nickel (Ni), plus some chromium (Cr), cobalt (Co), iron (Fe) and/or manganese (Mn). All these compounds play the same role: reversibly forming metal hydrides. When the battery is charged, hydrogen ions (H+) in the potassium hydroxide (KOH) electrolyte will be released and absorbed by these compounds to avoid the formation of hydrogen (H2), thus maintaining the internal pressure and volume of the battery. When the battery is discharged, these hydrogen ions will return to their original places through the opposite process. The positive active material of Ni-MH battery is nickel hydroxide (called nickel oxide electrode), the negative active material is metal oxide, also called hydrogen storage alloy (called hydrogen storage electrode), and the electrolyte is 6N potassium hydroxide. The battery reaction in the process of battery charging and discharging is as follows: where m represents hydrogen storage alloy material. The open-circuit voltage of the battery is: 1.2V ~ 1.3V, which varies with different hydrogen storage materials and preparation processes. The ordinary Ni-MH battery produced by Sanyo Company was invented by Plante in 1859. It consists of five basic parts: positive plate, negative plate, electrolyte, diaphragm and container (battery tank). The battery is made of lead dioxide as positive active material, lead as negative active material, sulfuric acid as electrolyte, microporous rubber, sintered PVC, glass fiber and polypropylene as diaphragm. The lead storage battery we use is a rectangular shell made of hard rubber or transparent plastic, and the grid is made of lead-antimony alloy containing 5% ~ 8% antimony. A layer of PbO2 is attached to the positive grid, and spongy metal lead is attached to the negative grid. Both poles are immersed in a certain concentration of sulfuric acid solution (the density is 1.25- 1.28 g/cm3), and microporous rubber or microporous plastic is used between the poles. The voltage of lead-acid battery is kept at 2.0V under normal conditions. When the voltage drops to 1.85V, that is, the sulfuric acid concentration drops and the solution density reaches 1. 18g/cm3, the battery needs to be charged. When the density increases to 1.28g/cm3, the charging should be stopped. Because of the good performance and low price of lead-acid batteries, many batteries used in automobiles are lead-acid batteries. It is widely used in national defense, scientific research, transportation, production and life because of its advantages of stable voltage, convenient use, safety and reliability, and recycling. The disadvantage of this battery is that it is relatively heavy. Negative electrode: Pb positive electrode: PbO2 electrolyte solution: 30%H2SO4 total reaction: Pb+PbO2+2H2SO4=2PbSO4↓+2H2O negative electrode reaction: Pb+SO42-+2e-=PbSO4 positive electrode reaction: PbO2+4h+SO4 2-+2e-= PbSO4+2H2O emergency. A lithium battery is mainly composed of a cathode, an anode, an electrolyte capable of conducting lithium ions and a diaphragm separating the cathode and the anode. The essence of lithium battery is concentration battery. Its anode and cathode materials are composed of two different lithium-ion intercalation compounds, the anode is a very different type of lithium-containing compound, and the cathode is a layered structure made of graphite, in which Li+ can be filled. As shown in fig. 3, during the charging process, lithium ions in the cathode are deintercalated, leaving lithium-containing compounds that move to the anode through the diaphragm and are embedded in the layered structure of the anode; On the contrary, in the process of discharge, lithium ions are deintercalated at the negative electrode, move to the positive electrode and combine with the compound of the positive electrode. Different from the traditional lithium battery, the redox substances are no longer Li and Li+, but Li+ is repeatedly deintercalated between the two poles with the change of oxidation state caused by the discharge of the bipolar material itself, so the lithium battery is also called Rockingchairbattery. A typical discharge principle of this battery is: positive electrode: CoO2+Li++e-=LiCoO2 negative electrode: lico 6-E-= 6c+Li+ Total reaction: Chief operating officer 2+LiCo6 = LiCoO2+6c According to the different electrolyte materials used in lithium-ion batteries, lithium-ion batteries can be divided into liquid lithium-ion batteries (LIB) and polymeric lithium-ion batteries (LIB). The anode and cathode materials used in polymer lithium ion batteries are the same as liquid lithium ion, and the working principle of the batteries is basically the same. The main difference between them is electrolyte. Lithium-ion batteries use liquid electrolyte, while polymer lithium-ion batteries use solid polymer electrolyte instead. This polymer can be "dry" or "colloidal". Because liquid electrolyte is replaced by solid electrolyte, compared with liquid lithium-ion battery, polymer lithium-ion battery has the advantages of thinning, arbitrary area, arbitrary shape, etc., and there will be no safety problems such as liquid leakage, combustion and explosion, so the battery shell can be made of aluminum-plastic composite film, which can improve the specific capacity of the whole battery. Polymer lithium-ion battery can also use polymer as cathode material, and its specific mass energy will be increased by more than 50% compared with the current liquid lithium-ion battery. In addition, polymer lithium-ion battery is superior to lithium-ion battery in working voltage, charge-discharge cycle life and so on. Based on the above advantages, polymer lithium-ion battery is known as the next generation lithium-ion battery. lithium battery