The lithium-ion battery - Backlinks USA

The modern car based battery

  

 In the 1970s, the development of lithium-ion batteries was started.The lithium battery has proved themselves to the best battery till then because of long operational time, extreme temperature or high power. An earlier lithium-ion battery cathode material contains different layered structures explained as Li-cobalt oxide (LiCoO2) or a tunneled structure named as Li-manganese oxide (LiMnO2).Were used as primary battery  in the 1960s,when the researchers focused on lithium as an anode on high energy density batteries.

 Therefore, the primary lithium batteries can be classified into several other categories, based on the type of anode and cathode material discussed briefly below.

   Types of lithium-ion batteries

 Lithium-sulfur dioxide battery 

The first lithium commercialized cell was introduced in the 1970s, lithium-sulfur dioxide (Li-SO2) cells. In this cell, carbon is placed as a cathode and lithium used as an anode. Teflon-bonded acetylene black supported on Al screen also serves as a cathode due to which cell provides high values of surface area, conductivity, and porosity. It has high conductivity even, and working voltage are 2.7 - 2.9V. As the tubular construction also provides a good energy density and a storing capacity of 34 A.h. However, the primary concern of this battery is its passivating film, which starts reducing its capacity when the concentration of SO2 is below 5%.

 

 Lithium-thionyl chloride battery

 These batteries were used because of their efficient energy density of 440 - 610 W.h/kg and the long-life span of 14 - 21 years. Moreover, certain batteries can be operated at an extensive temperature. As similar to a Li-SO2 battery, Li-SOCl2 also has porous carbon as a cathode, the solvent for the electrolyte salt and SOCl2 acts as an anode. In this, the main component to form the passivating film on the anode is LiCl. Hence, to increase the capacity of cell AlCl3 is adding in excess to the electrolyte.

 Lithium-manganese dioxide battery

 Li-MnO2 was introduced in 1975 and also known as solid cathode primary batteries. These are widely used due to certain advantages followed as relatively high energy density, high working voltage, nominal operating temperature range, long lifespan, and low cost. The most widely used electrolyte is LiClO4-PC-DME. Li-MnO2 can be constructed in various forms according to its applications such as cylindrical, cover coin and prismatic structures.

Lithium-carbon monofluoride battery

 Another solid-cathode primary battery is made with Li-C monofluoride (Li-CFx) battery, in which polycarbonate fluoride is used as a cathode. In this, Carbon enhances the electronic conductivity of the cathode material. Hence, the CFx system has advanced features and shows the flat operating voltage profile (2.8 V), energy density (200 - 600 W.h/kg),with a high capacity and full temperature range. Also, Li-CFx also shows the self-discharge rate among all lithium batteries. Although there are many more lithium primary batteries, which are designed for various types of applications such as cell phones, notebooks, etc.

Lithium-sulfur and lithium-air batteries

Li-S holds unique advantages to achieve the demand for renewable energy. Since, sulfur as a cathode is considered for the battery which leads to specific advantages like optimum cost, good specific energy and eco-friendly. However, both lithium and sulfur are light in weight and good in exerting multielectron conversion electro-chemistry which has a high specific energy.Lithium-sulfur battery also shows low coulombic efficiency due to its shuttling effect and its capacity fades rapidly. Moreover, the modern advancement in Li-sulfur batteries has been done because of the increasing demands of high storage energy system, and it also gives many opportunities to solve their issues related to bulk material's conductivity.The other most developing Li batteries regarding energy density are lithium-air system since the cathode active mass material is not included in these batteries. The excellent advantage of the lithium-air battery is its energy density of 3621 W.h/kg. Li-air gives competition with liquid fuels.In a non-aqueous Li-air battery, the primary focus is its pore volume for higher conductivity and low cost.

   How Li-ion battery works

 Lithium-ion batteries often use lithium cobalt oxide (LiCoO2) as the positive electrode and graphite as the negative electrode.When the batteries charge.lithium ions and electrons move from the positive to the negative electrode.When they discharge the ions and electrons move from the negative to the positive electrode.powering phones and other devices.the ions move through an electrolyte.typically made of a lithium salt dissolved in an organic liquid.

   Why Lithium-ion batteries catch fire

  Short- Circuiting

  A porous separator keeps the battery electrodes apart, charging the battery for long periods or inflicting a mechanical blow can damage the separator,causing the battery to discharge rapidly and generate a lot of heat.

    Over-charging

 When overcharged, lithium cobalt oxide releases oxygen. This can react with the flammable electrolyte and also with cobalt oxide (Co3 O4) left over after the release of oxygen, Co3 O4 also increases the resistance of the battery,raising the risk of overheating.

   Electrolyte breakdown

 During charging,some of the organic molecules in the electrolyte can break down, forming carbon dioxide.Because the battery is sealed, this causes pressure to build up.If it gets high enough, the battery bursts, exposing the flammable electrolyte.