[November Thematic Report] Savior Energy type

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[November Thematic Report] Savior Energy type
by Intqam Huseynov \| 13-11-2022 20:24 0
What is a battery and how does it work? Basics of Electrochemistry Basic electro-chemical processes such as using redox reactions to create a flow of electrons are the basis for how batteries work. Most batteries or cells are based off of the galvanic cell. Good examples of batteries based off of galvanic cells are dry cell batteries commonly used in flashlights and transistor radios; lead storage batteries which are your car batteries; and lithium-ion batteries normally found in cell phones, digital cameras, laptops, and electric vehicles. Galvanic cells contain cathodes and anodes with some form of an electron salt bridge. The cathode is negatively charged, where reduction occurs, and where electrons are gained. The opposite end of the spectrum on the battery is the anode which is positively charged and where electrons are lost. It should be noted that this is when the cell is operating. Salt bridges help facilitate the longevity of the battery and complete the circuit for the flow of electrons. Without the salt bridge electrons would not flow from cation to anion since the circuit would not be complete and a buildup of residue that collects from using the battery would render it useless as no charge would be created. An important difference between modern batteries and classic galvanic cells is that new batteries are complete self-contained and require no salt bridges giving them an advantage over classic galvanic cells. Instead of salt bridges batteries use some form of an electrolyte, which simply put is a substance that can conduct electricity when dissolved in water. The flow of electrons in batteries is measured by the difference in electrical potential from the anode, oxidized part, and cathode, positive part, and is measured by a voltmeter. The voltage across these cells is called the batteries cell voltage, cell potential, and often referred to as the cell’s emf (electromotive force). It is important to remember that these are all measured in volts. How does one determine what elements to use for cathodes and anodes though? Using standard reduction potentials one can see which elements are best for creating batteries. Looking at the equation for how cell potential is determined helps understand why certain elements are better as anodes and some as cathodes. Eºcell = Eºcathode-Eºanode remember the cathode is where reduction occurs and where electrons are gained. When looking at a standard table of reduction potentials it shows how likely an element is to be reduced or gain electrons thus the higher or more positive the reduction potential the more likely to be reduced and the lower or more negative the reduction potential the more likely the element is to be oxidized and lose electrons. This means that the best batteries are created by having an element with a high reduction potential to have a good cathode and an element with a very low reduction potential as the anode to create the biggest difference and highest voltage output. Dry Cells Dry cell batteries also known as the Leclanché cell are commonly used in devices such as flashlights. These batteries contain no fluid in them, hence the name dry cell. Dry cells have a graphite cathode rod in center and a zinc anode. These are both in contact with a mixture of manganese dioxide MnO2 and carbon which contact the outside of the rod and zinc plate to help with the flow of electrons. However, as mentioned earlier batteries need to have some form of electron carrier, whether it be a salt bridge or electrolyte solution of some form. In these cells a pasty like substance is used which contain electrolytes, usually composed of zinc (II) chloride ZnCl2 and ammonium chloride NH4Cl. This substance is used instead of a typical aqueous, dissolved in water, electrolyte because it creates a safer and less likely to leak battery. The battery then has a thin paper spacer around the paste, cathode, and anode and is then finally enclosed in a protective coating composed of some form of steel. Generally these cells produce around 1.5 volts of energy. What are some advantages of Li-ion batteries? Compared to the other high-quality rechargeable battery technologies (nickel-cadmium or nickel-metal-hydride), Li-ion batteries have a number of advantages. They have one of the highest energy densities of any battery technology today (100-265 Wh/kg or 250-670 Wh/L). In addition, Li-ion battery cells can deliver up to 3.6 Volts, 3 times higher than technologies such as Ni-Cd or Ni-MH. This means that they can deliver large amounts of current for high-power applications, which has Li-ion batteries are also comparatively low maintenance, and do not require scheduled cycling to maintain their battery life. Li-ion batteries have no memory effect, a detrimental process where repeated partial discharge/charge cycles can cause a battery to ‘remember’ a lower capacity. This is an advantage over both Ni-Cd and Ni-MH, which display this effect. Li-ion batteries also have low self-discharge rate of around 1.5-2% per month. They do not contain toxic cadmium, which makes them easier to dispose of than Ni-Cd batteries. Due to these advantages, Li-ion batteries have displaced Ni-Cd batteries as the market leader in portable electronic devices (such as smartphones and laptops). Li-ion batteries are also used to power electrical systems for some aerospace applications, notable in the new and more environmentally friendly Boeing 787, where weight is a significant cost factor. From a clean energy perspective, much of the promise of Li-ion technology comes from their potential applications in battery-powered cars. Currently, the bestselling electric cars, the Nissan Leaf and the Tesla Model S, both use Li-ion batteries as their primary fuel source. Lightweight: Compared to other battery chemistries, lithium provides the same or greater energy at less than half the weight and size. This translates into more flexibility and easier installation. Prolonged Service Life: In general, battery life expectancy is highly dependent on where and how the battery is being used. Lithium-ion batteries are known for their prolonged service life if used correctly. Overall, lithium-ion batteries last 2 to 3 times longer than similarly rated lead acid batteries. High Energy Density: A battery with high energy density can deliver the same amount of energy but in a smaller footprint compared to a battery with lower energy density. This is what makes lithium-ion batteries a suitable choice for electric vehicles. Low Self-Discharge Rate: All batteries experience some amount of self-discharge, but the rate at which this discharge happens depends on a few different factors such as temperature, battery type, and the initial charging state. For lithium-ion batteries, the self-discharge rate is much lower than that of lead acid batteries. According to electronics-notes.com, this rate is typically around 5% in the first four hours after being charged but then falls to around 1 or 2% per month while the discharge rate of lead acid batteries can be up to 5 times higher, as mentioned by power-sonic.com. A lithium-ion (Li-ion) battery is an advanced battery technology that uses lithium ions as a key component of its electrochemistry. During a discharge cycle, lithium atoms in the anode are ionized and separated from their electrons. The lithium ions move from the anode and pass through the electrolyte until they reach the cathode, where they recombine with their electrons and electrically neutralize. The lithium ions are small enough to be able to move through a micro-permeable separator between the anode and cathode. In part because of lithium’s small size (third only to hydrogen and helium), Li-ion batteries are capable of having a very high voltage and charge storage per unit mass and unit volume. What are some disadvantages of Li-ion batteries? Despite their technological promise, Li-ion batteries still have a number of shortcomings, particularly with regards to safety. Li-ion batteries have a tendency to overheat, and can be damaged at high voltages. In some cases this can lead to thermal runaway and combustion. This has caused significant problems, notably the grounding of the Boeing 787 fleet after onboard battery fires were reported. Because of the risks associated with these batteries, a number of shipping companies refuse to perform bulk shipments of batteries by plane. Li-ion batteries require safety mechanisms to limit voltage and internal pressures, which can increase weight and limit performance in some cases. Li-ion batteries are also subject to aging, meaning that they can lose capacity and frequently fail after a number of years. Another factor limiting their widespread adoption is their cost, which is around 40% higher than Ni-Cd. Addressing these issues is a key component for current research into the technology. Finally, despite the high energy density of Li-ion compared to other kinds of batteries, they are still around a hundred times less energy dense than gasoline (which contains 12,700 Wh/kg by mass or 8760 Wh/L by volume).

Former E-gen Ambassador Intqam Huseynov

3 Comments

Minkyung Mentor

Minkyung Mentor says :
Hello, this is your mentor Minkyung.

Thank you for sharing information on batteries. Because you mentioned both the advantages and disadvantages of Li-ion batteries, I could gain a balanced view of them.

For the record, please include the references of the photos and explain what they describe.

I'll be looking forward to your next report :)
Posted 20-11-2022 13:15

Junghyun Mentor Yoon says :
Hi, Intqam Huseynov!
This is your mentor, Yoon.

Thank you for introducing how the battery works. Your article is well structured. Your writing is also clear and concise. It is easy to follow and you used appropriate words to demonstrate the principles of LIBs.

Please be sure to include the references of the photos.

Great job on writing the thematic report.
I am looking forward to reading your following report!
Posted 15-11-2022 13:03

Intqam Huseynov