Chemical Battery
Chemical energy directly into electrical energy. The main part of the electrolyte solution, laptop battery soaked in the solution of the positive and negative electrodes and electrode wires to connect. Recovery based on whether the charge is divided into two kinds of primary batteries and battery
The types of chemical batteries
Chemical batteries, according to the nature of work can be divided into: one battery (original battery); secondary batteries (rechargeable batteries); lead-acid batteries. Of which: primary battery can be divided into: paste-type zinc-manganese batteries, cardboard zinc-manganese batteries, alkaline zinc-manganese batteries, zinc-silver button batteries, lithium button battery, button zinc-manganese batteries, zinc-air battery, a lithium manganese batteries. Secondary battery can be divided into: Nickel-cadmium batteries, nickel hydrogen batteries, lithium-ion battery, secondary alkaline zinc-manganese batteries. Lead-acid batteries can be divided into: open-type lead-acid batteries, all sealed lead-acid batteries.
1. Zn-Mn batteries
Zinc-manganese dioxide batteries (referred to as zinc-manganese batteries) also known as the McLellan Agency (Leclanche) batteries, is a French scientist McLellan Agency Hp Pavilion DV1000 battery (Hp dv1000 battery) (Leclanche ,1839-1882) was invented in 1868 by the zinc (Zn) as cathode, manganese dioxide (MnO2) as the cathode, electrolyte solution of neutral ammonium chloride (NH4Cl), zinc oxide (ZnCl2) in aqueous solution, surface layer of starch or paper pulp as an isolation layer made of zinc-manganese battery, said battery electrolyte solution is usually due to its system into a gel or adsorbed on other carriers but show no flow condition, it is also called zinc-manganese dry battery. By using the isolation layer is divided into two kinds of paste-type and the battery plate, plate and again under a different sub-ammonium liquid electrolyte type and zinc-based battery cells two kinds of cardboard.
Battery system with zinc anode for cylindrical shell, located in the central cap on the copper cap for cathode graphite rods, graphite rods around the outside from the inside followed by A: Manganese dioxide powder (black )------ used to absorb the hydrogen generated in the cathode (to prevent the resulting polarization); B: with saturated ammonium chloride and zinc chloride as the electrolyte solution of starch paste.
Electrode reaction type as follows: negative (Zinc): Zn + - 2e === Zn (NH3) 2Cl2 ↙ +2 H +
Positive (graphite): 2NH4 + === 2NH3 ↑ + H2 ↑
H2O + 2MnO2 + 2e === 2MnOOH + 2OH -
The overall reaction: Zn + 2NH4Cl + 2MnO2 === Zn (NH3) 2Cl2 ↙ +2 MnOOH
Battery voltage is about 1.5V, can not charge regeneration.
2. Alkaline zinc-manganese batteries
In the mid-20th century, developed on the basis of zinc-manganese batteries, is improved zinc-manganese battery. Hp PF723A battery Battery potassium hydroxide (KOH) or sodium hydroxide (NaOH) in aqueous electrolyte solution made, using zinc-manganese batteries with the opposite anode structure, and negative for the paste, including colloid, to do with Brass Nails collection fluid, positive outside, active substance and the conductive material pressed into the ring and the battery shell connection, positive and negative is made with special membrane separating the battery.
3. Lead-acid batteries
1859 France Plante (Plante) was found from the positive plates, negative plates, electrolyte, separators, containers (battery slot), etc. 5 basic parts. With lead dioxide as positive electrode active material, lead to negative active material, sulfuric acid as the electrolyte, porous rubber, sintered polyvinyl chloride, glass fiber, polypropylene, made for the battery separator.
Lead-acid batteries can discharge can also be charged, generally with a hard rubber or transparent plastic rectangular housing (to prevent the leakage of acid); with multi-electrode plates, which have a layer of brown color cathode plate of lead dioxide and negative is a sponge shaped metal lead, between the positive and negative electrodes with micro-porous rubber or plastic sheeting separated (to prevent short circuit between electrodes); Hp Pavilion ZV6000 battery (Hp zv6000 battery) poles are immersed into the sulfuric acid solution. Discharge the original battery, its electrode reaction as follows:
Anode: Pb + SO42 - 2e === PbSO4
Positive: PbO2 + 4H + + SO42-+ 2e === PbSO4 + 2H2O
The overall reaction formula: Pb + PbO2 + 2H2SO4 ====== 2PbSO4 + 2H2O
When the discharge proceeds, the concentration of sulfuric acid solution will continue to decrease, when the density of the solution should be to stop the use of reduced 1.18g/ml charging, charging for the electrolytic cell, the electrode reaction is as follows:
Anode: PbSO4 + 2H2O-2e === PbO2 + 4H + + SO42 -
Cathode: PbSO4 + 2e === Pb + SO42 -
The overall reaction formula: 2PbSO4 + 2H2O ====== Pb + PbO2 + 2H2SO4
When the density of the solution rose to 1.28g/ml, they should stop charging.
The total reactive above process as follows:
Discharge
Pb + PbO2 + 2H2SO4 ====== 2PbSO4 + 2H2O
Charge
4. Zinc-silver battery
Usually made of small round stainless steel box-shaped, round box from the positive and negative shell shell composition,Hp Pavilion ZV5000 battery (Hp zv5000 battery) the shape of buttons (commonly known as button batteries). Positive end-shell box filled with silver and graphite formed by the oxidation of the cathode active material, negative electrode cap at one end filled with amalgam composed of zinc anode active material and electrolyte solution as the concentrated KOH solution. Electrode reaction type is as follows:
Anode: Zn + 2OH--2e === ZnO + H2O
Positive: Ag2O + H2O + 2e === 2Ag + 2OH -
The total cell reaction is: Ag2O + Zn ====== 2Ag + ZnO
The battery voltage is typically 1.59V, a longer service life.
5. Nickel-cadmium batteries and nickel hydride and nickel-metal hydride batteries
Both use nickel oxide or nickel hydroxide as positive to potassium hydroxide or sodium hydroxide aqueous solution as electrolyte solution, metal cadmium or metal hydride as anode. Metal hydride batteries to the 20th century, late 80s, the use of hydrogen absorption and release of hydrogen alloy electrochemical reversibility of the invention is made of the leading products of small secondary battery.
6. Lithium batteries
Lithium batteries Compaq Presario X6000 battery are a class of substances with lithium metal or alloys as anode materials for lithium chemical power of the general known as lithium batteries, is divided into a lithium battery and rechargeable lithium battery.
7. Lithium-ion battery
That lithium ion can embed and de-embedding of carbon materials as anode instead of pure lithium and lithium compounds as positive, mixed-electrolyte to electrolyte solution made of batteries. Lithium-ion batteries in 1990, Sony Corporation of Japan developed the technology first and foremost their products. At home and abroad have been commercialized lithium-ion battery cathode is LiCoO2, negative is a layered graphite, the electrochemical cell expression (-) C6 ▏ 1mol / L LiPF6-EC + DEC ▏ LiCoO2 (+)
8. Hydrogen-oxygen fuel cell
This is an efficient, less polluting new battery, mainly for space. The electrode material is generally activated electrodes, has a strong catalytic activity, such as the platinum electrodes, activated carbon electrodes. Electrolyte solution is generally 40% of the KOH solution. Electrode reaction type is as follows:
Anode: 2H2 + 4OH--4e === 4H2O
Cathode: O2 + 2H2O + 4e === 4OH -
The overall reaction type: 2H2 + O2 === 2H2O
9. Molten salt fuel cells
This is a very high power generation efficiency of high-power chemical batteries, in Canada and a few other developed countries have been close to civilian level of industrialization. According to its use of different fuels or molten salt, there are many different varieties, such as natural gas, CO, --- molten carbonate type, fused phosphate type, etc., generally at a certain high temperature Compaq Presario R3000 battery (Compaq r3000 battery) (to ensure that salt is molten state ) to work.
Here in CO --- Li2CO3 + Na2CO3 --- air and CO2-based batteries as an example to illustrate:
Negative Reactive: 2CO + 2CO32 - 4e === 4CO2
Positive Reactive: O2 + 2CO2 + 4e === 2CO32 -
The overall reaction formula is: 2CO + O2 === 2CO2
The battery's operating temperature is generally 6500C
10. Seawater battery
In 1991, Chinese scientists have pioneered in the air --- --- aluminum material composition of sea water for a new battery, used as a navigation marker lamps. The battery with an inexhaustible supply of seawater as electrolyte, by oxygen in the air so that continuous oxidation of aluminum to generate electricity. The electrode reaction-type is as follows:
Cathode: 4Al - 12e === 4Al3 +
Positive: 3O2 + 6H2O + 12e === 12OH -
The total reaction is: 4Al + 3O2 + 6H2O === 4Al (OH) 3
This battery energy than normal batteries to 20 --- 50 times!
New chemical batteries
(An alkaline hydrogen-oxygen fuel cell
This battery with 30% -50% KOH as electrolyte, at 100 ° C the following tasks. Fuel is hydrogen, oxidant is oxygen. The battery icon for the (-) C | H2 | KOH | O2 | C (+)
Battery negative reaction 2H2 + 4OH-4e = 4H2O Cathode O2 + 2H2O + 4e = 4OH
The overall reaction 2H2 + O2 = 2H2O
Alkaline hydrogen-oxygen fuel cell has long been in the 60s of this century, the U.S. manned spacecraft on the application, the also used in forklifts, Compaq PP2100 battery tractors and so on, but as the prospect of civilian products is also mixed. Used by those who deny that the battery is easy with the KOH electrolyte fuel gas or air from the CO2 in the reaction of carbonate poor electrical conductivity. In addition, although the noble metal catalyst fuel cells needed to load a low, but the actual life expectancy is limited. Certainly those who think that the fuel cell materials are cheaper, if the use of natural gas as fuel, it only has been commercialized than the phosphoric acid fuel cell costs even lower.
(2) phosphoric acid fuel cell
It uses phosphoric acid as the electrolyte, the use of inexpensive carbon materials for the skeleton. It is divided by the hydrogen as fuel, it now may also the direct use of methanol, natural gas, city gas and other low-cost fuel, in comparison with the alkaline hydrogen-oxygen fuel cells, the biggest advantage is that it does not require CO2 processing equipment. Phosphoric Acid Fuel Cell has become the fastest-growing, and is currently the most mature fuel cell, fuel cells, it represents the main direction of development. The capacity of the world's largest fuel cell power plants are operated by Tokyo Electric Energy 11MW US-Japan cooperation in phosphoric acid fuel cell power plant,Hp DP390A battery the plant has been built since 1991, running well. In recent years, put into operation more than 100 fuel cell power generation system, 90% phosphoric acid type. The market supply of main types of phosphate-based power generation system with Japan's Fuji Electric Company 50KW or 100KW and the U.S. Agency for International Fuel Cells provide 200KW.
Fuji Electric has provided more than 70 power stations, on-site life of more than 100,000 hours.
Phosphoric Acid Fuel Cell current problems to be solved is: how to prevent catalyst agglomeration caused by contraction and surface area of catalyst reduction, as well as how to further reduce the cost of equipment.
The significance of chemical power sources:
Chemical energy is converted to electrical energy principles of discovery and invention of various devices, the battery is stored energy and energy technology for the tremendous progress in the chemical a major contribution to humanity, which greatly promoted the modernization process, changing the people's lifestyle, and enhance people's quality of life